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Sialylation of Asparagine 612 Inhibits Aconitase Activity during Mouse Sperm Capacitation; a Possible Mechanism for the Switch from Oxidative Phosphorylation to Glycolysis [Research]

After ejaculation, mammalian spermatozoa must undergo a process known as capacitation in order to successfully fertilize the oocyte. Several post-translational modifications occur during capacitation, including sialylation, which despite being limited to a few proteins, seems to be essential for proper sperm-oocyte interaction. Regardless of its importance, to date, no single study has ever identified nor quantified which glycoproteins bearing terminal sialic acid (Sia) are altered during capacitation. Here we characterize sialylation during mouse sperm capacitation. Using tandem MS coupled with liquid chromatography (LC–MS/MS), we found 142 nonreductant peptides, with 9 of them showing potential modifications on their sialylated oligosaccharides during capacitation. As such, N-linked sialoglycopeptides from C4b-binding protein, endothelial lipase (EL), serine proteases 39 and 52, testis-expressed protein 101 and zonadhesin were reduced following capacitation. In contrast, mitochondrial aconitate hydratase (aconitase; ACO2), a TCA cycle enzyme, was the only protein to show an increase in Sia content during capacitation. Interestingly, although the loss of Sia within EL (N62) was accompanied by a reduction in its phospholipase A1 activity, a decrease in the activity of ACO2 (i.e. stereospecific isomerization of citrate to isocitrate) occurred when sialylation increased (N612). The latter was confirmed by N612D recombinant protein tagged with both His and GFP. The replacement of Sia for the negatively charged Aspartic acid in the N612D mutant caused complete loss of aconitase activity compared with the WT. Computer modeling show that N612 sits atop the catalytic site of ACO2. The introduction of Sia causes a large conformational change in the alpha helix, essentially, distorting the active site, leading to complete loss of function. These findings suggest that the switch from oxidative phosphorylation, over to glycolysis that occurs during capacitation may come about through sialylation of ACO2.




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Quantitative Proteomics Links the LRRC59 Interactome to mRNA Translation on the ER Membrane [Research]

Protein synthesis on the endoplasmic reticulum (ER) requires the dynamic coordination of numerous cellular components. Together, resident ER membrane proteins, cytoplasmic translation factors, and both integral membrane and cytosolic RNA-binding proteins operate in concert with membrane-associated ribosomes to facilitate ER-localized translation. Little is known, however, regarding the spatial organization of ER-localized translation. This question is of growing significance as it is now known that ER-bound ribosomes contribute to secretory, integral membrane, and cytosolic protein synthesis alike. To explore this question, we utilized quantitative proximity proteomics to identify neighboring protein networks for the candidate ribosome interactors SEC61β (subunit of the protein translocase), RPN1 (oligosaccharyltransferase subunit), SEC62 (translocation integral membrane protein), and LRRC59 (ribosome binding integral membrane protein). Biotin labeling time course studies of the four BioID reporters revealed distinct labeling patterns that intensified but only modestly diversified as a function of labeling time, suggesting that the ER membrane is organized into discrete protein interaction domains. Whereas SEC61β and RPN1 reporters identified translocon-associated networks, SEC62 and LRRC59 reporters revealed divergent protein interactomes. Notably, the SEC62 interactome is enriched in redox-linked proteins and ER luminal chaperones, with the latter likely representing proximity to an ER luminal chaperone reflux pathway. In contrast, the LRRC59 interactome is highly enriched in SRP pathway components, translation factors, and ER-localized RNA-binding proteins, uncovering a functional link between LRRC59 and mRNA translation regulation. Importantly, analysis of the LRRC59 interactome by native immunoprecipitation identified similar protein and functional enrichments. Moreover, [35S]-methionine incorporation assays revealed that siRNA silencing of LRRC59 expression reduced steady state translation levels on the ER by ca. 50%, and also impacted steady state translation levels in the cytosol compartment. Collectively, these data reveal a functional domain organization for the ER and identify a key role for LRRC59 in the organization and regulation of local translation.




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High-speed Analysis of Large Sample Sets - How Can This Key Aspect of the Omics Be Achieved? [Perspective]

High-speed analysis of large (prote)omics sample sets at the rate of thousands or millions of samples per day on a single platform has been a challenge since the beginning of proteomics. For many years, ESI-based MS methods have dominated proteomics because of their high sensitivity and great depth in analyzing complex proteomes. However, despite improvements in speed, ESI-based MS methods are fundamentally limited by their sample introduction, which excludes off-line sample preparation/fractionation because of the time required to switch between individual samples/sample fractions, and therefore being dependent on the speed of on-line sample preparation methods such as liquid chromatography. Laser-based ionization methods have the advantage of moving from one sample to the next without these limitations, being mainly restricted by the speed of modern sample stages, i.e. 10 ms or less between samples. This speed matches the data acquisition speed of modern high-performing mass spectrometers whereas the pulse repetition rate of the lasers (>1 kHz) provides a sufficient number of desorption/ionization events for successful ion signal detection from each sample at the above speed of the sample stages. Other advantages of laser-based ionization methods include the generally higher tolerance to sample additives and contamination compared with ESI MS, and the contact-less and pulsed nature of the laser used for desorption, reducing the risk of cross-contamination. Furthermore, new developments in MALDI have expanded its analytical capabilities, now being able to fully exploit high-performing hybrid mass analyzers and their strengths in sensitivity and MS/MS analysis by generating an ESI-like stable yield of multiply charged analyte ions. Thus, these new developments and the intrinsically high speed of laser-based methods now provide a good basis for tackling extreme sample analysis speed in the omics.




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OpenPepXL: An Open-Source Tool for Sensitive Identification of Cross-Linked Peptides in XL-MS [Technological Innovation and Resources]

Cross-linking MS (XL-MS) has been recognized as an effective source of information about protein structures and interactions. In contrast to regular peptide identification, XL-MS has to deal with a quadratic search space, where peptides from every protein could potentially be cross-linked to any other protein. To cope with this search space, most tools apply different heuristics for search space reduction. We introduce a new open-source XL-MS database search algorithm, OpenPepXL, which offers increased sensitivity compared with other tools. OpenPepXL searches the full search space of an XL-MS experiment without using heuristics to reduce it. Because of efficient data structures and built-in parallelization OpenPepXL achieves excellent runtimes and can also be deployed on large compute clusters and cloud services while maintaining a slim memory footprint. We compared OpenPepXL to several other commonly used tools for identification of noncleavable labeled and label-free cross-linkers on a diverse set of XL-MS experiments. In our first comparison, we used a data set from a fraction of a cell lysate with a protein database of 128 targets and 128 decoys. At 5% FDR, OpenPepXL finds from 7% to over 50% more unique residue pairs (URPs) than other tools. On data sets with available high-resolution structures for cross-link validation OpenPepXL reports from 7% to over 40% more structurally validated URPs than other tools. Additionally, we used a synthetic peptide data set that allows objective validation of cross-links without relying on structural information and found that OpenPepXL reports at least 12% more validated URPs than other tools. It has been built as part of the OpenMS suite of tools and supports Windows, macOS, and Linux operating systems. OpenPepXL also supports the MzIdentML 1.2 format for XL-MS identification results. It is freely available under a three-clause BSD license at https://openms.org/openpepxl.




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ProAlanase is an Effective Alternative to Trypsin for Proteomics Applications and Disulfide Bond Mapping [Technological Innovation and Resources]

Trypsin is the protease of choice in bottom-up proteomics. However, its application can be limited by the amino acid composition of target proteins and the pH of the digestion solution. In this study we characterize ProAlanase, a protease from the fungus Aspergillus niger that cleaves primarily on the C-terminal side of proline and alanine residues. ProAlanase achieves high proteolytic activity and specificity when digestion is carried out at acidic pH (1.5) for relatively short (2 h) time periods. To elucidate the potential of ProAlanase in proteomics applications, we conducted a series of investigations comprising comparative multi-enzymatic profiling of a human cell line proteome, histone PTM analysis, ancient bone protein identification, phosphosite mapping and de novo sequencing of a proline-rich protein and disulfide bond mapping in mAb. The results demonstrate that ProAlanase is highly suitable for proteomics analysis of the arginine- and lysine-rich histones, enabling high sequence coverage of multiple histone family members. It also facilitates an efficient digestion of bone collagen thanks to the cleavage at the C terminus of hydroxyproline which is highly prevalent in collagen. This allows to identify complementary proteins in ProAlanase- and trypsin-digested ancient bone samples, as well as to increase sequence coverage of noncollagenous proteins. Moreover, digestion with ProAlanase improves protein sequence coverage and phosphosite localization for the proline-rich protein Notch3 intracellular domain (N3ICD). Furthermore, we achieve a nearly complete coverage of N3ICD protein by de novo sequencing using the combination of ProAlanase and tryptic peptides. Finally, we demonstrate that ProAlanase is efficient in disulfide bond mapping, showing high coverage of disulfide-containing regions in a nonreduced mAb.




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ReactomeGSA - Efficient Multi-Omics Comparative Pathway Analysis [Technological Innovation and Resources]

Pathway analyses are key methods to analyze 'omics experiments. Nevertheless, integrating data from different 'omics technologies and different species still requires considerable bioinformatics knowledge.

Here we present the novel ReactomeGSA resource for comparative pathway analyses of multi-omics datasets. ReactomeGSA can be used through Reactome's existing web interface and the novel ReactomeGSA R Bioconductor package with explicit support for scRNA-seq data. Data from different species is automatically mapped to a common pathway space. Public data from ExpressionAtlas and Single Cell ExpressionAtlas can be directly integrated in the analysis. ReactomeGSA greatly reduces the technical barrier for multi-omics, cross-species, comparative pathway analyses.

We used ReactomeGSA to characterize the role of B cells in anti-tumor immunity. We compared B cell rich and poor human cancer samples from five of the Cancer Genome Atlas (TCGA) transcriptomics and two of the Clinical Proteomic Tumor Analysis Consortium (CPTAC) proteomics studies. B cell-rich lung adenocarcinoma samples lacked the otherwise present activation through NFkappaB. This may be linked to the presence of a specific subset of tumor associated IgG+ plasma cells that lack NFkappaB activation in scRNA-seq data from human melanoma. This showcases how ReactomeGSA can derive novel biomedical insights by integrating large multi-omics datasets.




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Stoichiometry of Nucleotide Binding to Proteasome AAA+ ATPase Hexamer Established by Native Mass Spectrometry [Research]

AAA+ ATPases constitute a large family of proteins that are involved in a plethora of cellular processes including DNA disassembly, protein degradation and protein complex disassembly. They typically form a hexametric ring-shaped structure with six subunits in a (pseudo) 6-fold symmetry. In a subset of AAA+ ATPases that facilitate protein unfolding and degradation, six subunits cooperate to translocate protein substrates through a central pore in the ring. The number and type of nucleotides in an AAA+ ATPase hexamer is inherently linked to the mechanism that underlies cooperation among subunits and couples ATP hydrolysis with substrate translocation. We conducted a native MS study of a monodispersed form of PAN, an archaeal proteasome AAA+ ATPase, to determine the number of nucleotides bound to each hexamer of the WT protein. We utilized ADP and its analogs (TNP-ADP and mant-ADP), and a nonhydrolyzable ATP analog (AMP-PNP) to study nucleotide site occupancy within the PAN hexamer in ADP- and ATP-binding states, respectively. Throughout all experiments we used a Walker A mutant (PANK217A) that is impaired in nucleotide binding as an internal standard to mitigate the effects of residual solvation on mass measurement accuracy and to serve as a reference protein to control for nonspecific nucleotide binding. This approach led to the unambiguous finding that a WT PAN hexamer carried – from expression host – six tightly bound ADP molecules that could be exchanged for ADP and ATP analogs. Although the Walker A mutant did not bind ADP analogs, it did bind AMP-PNP, albeit at multiple stoichiometries. We observed variable levels of hexamer dissociation and an appearance of multimeric species with the over-charged molecular ion distributions across repeated experiments. We posit that these phenomena originated during ESI process at the final stages of ESI droplet evolution.




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A Comprehensive Gender-related Secretome of Plasmodium berghei Sexual Stages [Research]

Plasmodium, the malaria parasite, undergoes a complex life cycle alternating between a vertebrate host and a mosquito vector of the genus Anopheles. In red blood cells of the vertebrate host, Plasmodium multiplies asexually or differentiates into gamete precursors, the male and female gametocytes, responsible for parasite transmission. Sexual stage maturation occurs in the midgut of the mosquito vector, where male and female gametes egress from the host erythrocytes to fuse and form a zygote. Gamete egress entails the successive rupture of two membranes surrounding the parasite, the parasitophorous vacuole membrane and the erythrocyte plasma membrane. In this study, we used the rodent model parasite Plasmodium berghei to design a label-free quantitative proteomic approach aimed at identifying gender-related proteins differentially released/secreted by purified mature gametocytes when activated to form gametes. We compared the abundance of molecules secreted by wild type gametocytes of both genders with that of a transgenic line defective in male gamete maturation and egress. This enabled us to provide a comprehensive data set of egress-related molecules and their gender specificity. Using specific antibodies, we validated eleven candidate molecules, predicted as either gender-specific or common to both male and female gametocytes. All of them localize to punctuate, vesicle-like structures that relocate to cell periphery upon activation, but only three of them localize to the gametocyte-specific secretory vesicles named osmiophilic bodies. Our results confirm that the egress process involves a tightly coordinated secretory apparatus that includes different types of vesicles and may put the basis for functional studies aimed at designing novel transmission-blocking molecules.




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Temporal Quantitative Proteomics of mGluR-induced Protein Translation and Phosphorylation in Neurons [Research]

At neuronal synapses, activation of group I metabotropic glutamate receptors (mGluR1/5) triggers a form of long-term depression (mGluR-LTD) that relies on new protein synthesis and the internalization of AMPA-type glutamate receptors. Dysregulation of these processes has been implicated in the development of mental disorders such as autism spectrum disorders and therefore merit a better understanding on a molecular level. Here, to study mGluR-induced signaling pathways, we integrated quantitative phosphoproteomics with the analyses of newly synthesized proteins via bio-orthogonal amino acids (azidohomoalanine) in a pulsed labeling strategy in cultured hippocampal neurons stimulated with DHPG, a specific agonist for group I mGluRs. We identified several kinases with important roles in DHPG-induced mGluR activation, which we confirmed using small molecule kinase inhibitors. Furthermore, changes in the AMPA receptor endocytosis pathway in both protein synthesis and protein phosphorylation were identified, whereby Intersectin-1 was validated as a novel player in this pathway. This study revealed several new insights into the molecular pathways downstream of group I mGluR activation in hippocampal neurons, and provides a rich resource for further analyses.




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A Mouse Brain-based Multi-omics Integrative Approach Reveals Potential Blood Biomarkers for Ischemic Stroke [Research]

Stroke remains a leading cause of death and disability worldwide. Despite continuous advances, the identification of key molecular signatures in the hyper-acute phase of ischemic stroke is still a primary interest for translational research on stroke diagnosis, prognosis, and treatment. Data integration from high-throughput -omics techniques has become crucial to unraveling key interactions among different molecular elements in complex biological contexts, such as ischemic stroke. Thus, we used advanced data integration methods for a multi-level joint analysis of transcriptomics and proteomics data sets obtained from mouse brains at 2 h after cerebral ischemia. By modeling net-like correlation structures, we identified an integrated network of genes and proteins that are differentially expressed at a very early stage after stroke. We validated 10 of these deregulated elements in acute stroke, and changes in their expression pattern over time after cerebral ischemia were described. Of these, CLDN20, GADD45G, RGS2, BAG5, and CTNND2 were next evaluated as blood biomarkers of cerebral ischemia in mice and human blood samples, which were obtained from stroke patients and patients presenting stroke-mimicking conditions. Our findings indicate that CTNND2 levels in blood might potentially be useful for distinguishing ischemic strokes from stroke-mimicking conditions in the hyper-acute phase of the disease. Furthermore, circulating GADD45G content within the first 6 h after stroke could also play a key role in predicting poor outcomes in stroke patients. For the first time, we have used an integrative biostatistical approach to elucidate key molecules in the initial stages of stroke pathophysiology and highlight new notable molecules that might be further considered as blood biomarkers of ischemic stroke.




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WITHDRAWN: Extraordinary apolipoprotein oxidation in chronic hepatitis C and liver cirrhosis [13. Other]

Withdrawn by Author.




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Oxidative stress-mediated regulation of proteasome complexes [Other]

Oxidative stress has been implicated in aging and many human diseases, notably neurodegenerative disorders and various cancers. The reactive oxygen species that are generated by aerobic metabolism and environmental stressors can chemically modify proteins and alter their biological functions. Cells possess protein repair pathways to rescue oxidized proteins and restore their functions. If these repair processes fail, oxidized proteins may become cytotoxic. Cell homeostasis and viability are therefore dependent on the removal of oxidatively damaged proteins. Numerous studies have demonstrated that the proteasome plays a pivotal role in the selective recognition and degradation of oxidized proteins. Despite extensive research, oxidative stress-triggered regulation of proteasome complexes remains poorly defined. Better understanding of molecular mechanisms underlying proteasome function in response to oxidative stress will provide a basis for developing new strategies aimed at improving cell viability and recovery as well as attenuating oxidation-induced cytotoxicity associated with aging and disease. Here we highlight recent advances in the understanding of proteasome structure and function during oxidative stress and describe how cells cope with oxidative stress through proteasome-dependent degradation pathways.




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Quantitative profiling of protein tyrosine kinases in human cancer cell lines by multiplexed parallel reaction monitoring assays [Technology]

Protein tyrosine kinases (PTKs) play key roles in cellular signal transduction, cell cycle regulation, cell division, and cell differentiation. Dysregulation of PTK-activated pathways, often by receptor overexpression, gene amplification, or genetic mutation, is a causal factor underlying numerous cancers. In this study, we have developed a parallel reaction monitoring (PRM)-based assay for quantitative profiling of 83 PTKs. The assay detects 308 proteotypic peptides from 54 receptor tyrosine kinases and 29 nonreceptor tyrosine kinases in a single run. Quantitative comparisons were based on the labeled reference peptide method. We implemented the assay in four cell models: 1) a comparison of proliferating versus epidermal growth factor (EGF)-stimulated A431 cells, 2) a comparison of SW480Null (mutant APC) and SW480APC (APC restored) colon tumor cell lines, and 3) a comparison of 10 colorectal cancer cell lines with different genomic abnormalities, and 4) lung cancer cell lines with either susceptibility (11-18) or acquired resistance (11-18R) to the epidermal growth factor receptor tyrosine kinase inhibitor erlotinib. We observed distinct PTK expression changes that were induced by stimuli, genomic features or drug resistance, which were consistent with previous reports. However, most of the measured expression differences were novel observations. For example, acquired resistance to erlotinib in the 11-18 cell model was associated not only with previously reported upregulation of MET, but also with upregulation of FLK2 and downregulation of LYN and PTK7. Immunoblot analyses and shotgun proteomics data were highly consistent with PRM data. Multiplexed PRM assays provide a targeted, systems-level profiling approach to evaluate cancer-related proteotypes and adaptations. Data are available through Proteome eXchange Accession PXD002706.




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WITHDRAWN: Quantitative mass spectrometry analysis of PD-L1 protein expression, N-glycosylation and expression stoichiometry with PD-1 and PD-L2 in human melanoma [Research]

This article has been withdrawn by the authors. We discovered an error after this manuscript was published as a Paper in Press. Specifically, we learned that the structures of glycans presented for the PD-L1 peptide were drawn and labeled incorrectly. We wish to withdraw this article and submit a corrected version for review.




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Translating Divergent Environmental Stresses into a Common Proteome Response through Hik33 in a Model Cyanobacterium [Research]

The histidine kinase Hik33 plays important roles in mediating cyanobacterial response to divergent types of abiotic stresses including cold, salt, high light (HL), and osmotic stresses. However, how these functions are regulated by Hik33 remains to be addressed. Using a hik33-deficient strain (hik33) of Synechocystis sp. PCC 6803 (Synechocystis) and quantitative proteomics, we found that Hik33 depletion induces differential protein expression highly similar to that induced by divergent types of stresses. This typically includes downregulation of proteins in photosynthesis and carbon assimilation that are necessary for cell propagation, and upregulation of heat shock proteins, chaperons, and proteases that are important for cell survival. This observation indicates that depletion of Hik33 alone mimics divergent types of abiotic stresses, and that Hik33 could be important for preventing abnormal stress response in the normal condition. Moreover, we found the majority of proteins of plasmid origin were significantly upregulated in hik33, though their biological significance remains to be addressed. Together, the systematically characterized Hik33-regulated cyanobacterial proteome, which is largely involved in stress responses, builds the molecular basis for Hik33 as a general regulator of stress responses.




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Meta-heterogeneity: evaluating and describing the diversity in glycosylation between sites on the same glycoprotein [Review]

Mass spectrometry-based glycoproteomics has gone through some incredible developments over the last few years. Technological advances in glycopeptide enrichment, fragmentation methods, and data analysis workflows have enabled the transition of glycoproteomics from a niche application, mainly focused on the characterization of isolated glycoproteins, to a mature technology capable of profiling thousands of intact glycopeptides at once. In addition to numerous biological discoveries catalyzed by the technology, we are also observing an increase in studies focusing on global protein glycosylation and the relationship between multiple glycosylation sites on the same protein. It has become apparent that just describing protein glycosylation in terms of micro- and macro-heterogeneity, respectively the variation and occupancy of glycans at a given site, is not sufficient to describe the observed interactions between sites. In this perspective we propose a new term, meta-heterogeneity, to describe a higher level of glycan regulation: the variation in glycosylation across multiple sites of a given protein. We provide literature examples of extensive meta-heterogeneity on relevant proteins such as antibodies, erythropoietin, myeloperoxidase and a number of serum and plasma proteins. Furthermore, we postulate on the possible biological reasons and causes behind the intriguing meta-heterogeneity observed in glycoproteins.




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Quantitative data independent acquisition glycoproteomics of sparkling wine [Research]

Sparkling wine is an alcoholic beverage enjoyed around the world. The sensory properties of sparkling wine depend on a complex interplay between the chemical and biochemical components in the final product. Glycoproteins have been linked to positive and negative qualities in sparkling wine, but the glycosylation profiles of sparkling wine have not been previously investigated in detail. We analysed the glyco/proteome of sparkling wines using protein- and glycopeptide-centric approaches. We developed an automated workflow that created ion libraries to analyse Sequential Window Acquisition of all THeoretical mass spectra (SWATH) Data Independent Acquisition (DIA) mass spectrometry data based on glycopeptides identified by Byonic. We applied our workflow to three pairs of experimental sparkling wines to assess the effects of aging on lees and of different yeast strains used in the Liqueur de Tirage for secondary fermentation. We found that aging a cuvée on lees for 24 months compared to 8 months led to a dramatic decrease in overall protein abundance and an enrichment in large glycans at specific sites in some proteins. Secondary fermentation of a Riesling wine with Saccharomyces cerevisiae yeast strain Siha4 produced more yeast proteins and glycoproteins than with S. cerevisiae yeast strain DV10. The abundance and glycosylation profiles of grape glycoproteins were also different between grape varieties. This work represents the first in-depth study into protein- and peptide-specific glycosylation in sparkling wines and describes a quantitative glycoproteomic SWATH/DIA workflow that is broadly applicable to other sample types.




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Glycomics, Glycoproteomics and Glycogenomics: an Inter-Taxa Evolutionary Perspective [Review]

Glycosylation is a highly diverse set of co- and post-translational modification of proteins. For mammalian glycoproteins, glycosylation is often site-, tissue- and species-specific, and diversified by microheterogeneity. Multitudinous biochemical, cellular, physiological and organismic effects of their glycans have been revealed, either intrinsic to the carrier proteins or mediated by endogenous reader proteins with carbohydrate recognition domains. Furthermore, glycans frequently form the first line of access by or defense from foreign invaders, and new roles for nucleocytoplasmic glycosylation are blossoming. We now know enough to conclude that the same general principles apply in invertebrate animals and unicellular eukaryotes – different branches of which spawned the plants or fungi and animals. The two major driving forces for exploring the glycomes of invertebrates and protists are (i) to understand the biochemical basis of glycan-driven biology in these organisms, especially of pathogens, and (ii) to uncover the evolutionary relationships between glycans, their biosynthetic enzyme genes, and biological functions for new glycobiological insights. With an emphasis on emerging areas of protist glycobiology, here we offer an overview of glycan diversity and evolution, to promote future access to this treasure trove of glycobiological processes.




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Peptidomics-driven strategy reveals peptides and predicted proteases associated with oral cancer prognosis [Research]

Protease activity has been associated with pathological processes that can lead to cancer development and progression. However, understanding the pathological unbalance in proteolysis is challenging since changes can occur simultaneously at protease, their inhibitor and substrate levels. Here, we present a pipeline that combines peptidomics, proteomics and peptidase predictions for studying proteolytic events in the saliva of seventy-nine patients and their association with oral squamous cell carcinoma (OSCC) prognosis. Our findings revealed differences in the saliva peptidome of patients with (pN+) or without (pN0) lymph node metastasis and delivered a panel of ten endogenous peptides correlated with poor prognostic factors plus five molecules able to classify pN0 and pN+ patients (ROC-AUC>0.85). In addition, endo- and exopeptidases putatively implicated in the processing of differential peptides were investigated using cancer tissue gene expression data from publicly repositories reinforcing their association with poorer survival rates and prognosis in oral cancer. The dynamics of the OSCC-related proteolysis was further explored via the proteomic profiling of saliva. This revealed that peptidase/endopeptidase inhibitors exhibited reduced levels in the saliva of pN+ patients, as confirmed by SRM-MS, whilst minor changes were detected in the level of saliva proteases. Taken together, our results indicated that proteolytic activity is accentuated in the saliva of OSCC patients with lymph node metastasis and, at least in part, this is modulated by reduced levels of salivary peptidase inhibitors. Therefore, this integrated pipeline provided better comprehension and discovery of molecular features with implications in the oral cancer metastasis prognosis.




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Quantitative proteomics reveal neuron projection development genes ARF4, KIF5B and RAB8A associated with Hirschsprung disease [Research]

Hirschsprung disease (HSCR) is a heterogeneous group of neurocristopathy characterized by the absence of the enteric ganglia along a variable length of the intestine. Genetic defects play a major role in the pathogenesis of HSCR while family studies of pathogenic variants in all the known genes (loci) only demonstrate incomplete penetrance and variable expressivity for unknown reasons. Here, we applied large-scale, quantitative proteomics of human colon tissues from 21 patients using iTRAQ method followed by bioinformatics analysis. Selected findings were confirmed by parallel reaction monitoring (PRM) verification. At last the interesting differentially expressed proteins were confirmed by western blot. A total of 5341 proteins in human colon tissues were identified. Among them, 664 proteins with >1.2-fold difference were identified in 6 groups: groups A1 and A2 pooled protein from the ganglionic and aganglionic colon of male, long-segment HSCR patients (L-HSCR, n=7); groups B1 and B2 pooled protein from the ganglionic and aganglionic colon of male, short-segment HSCR patients (S-HSCR, n=7); and groups C1 and C2 pooled protein from the ganglionic and aganglionic colon of female, S-HSCR patients (n=7). Based on these analyses, 49 proteins from 5 pathways were selected for PRM verification, including ribosome, endocytosis, spliceosome, oxidative phosphorylation and cell adhesion. The downregulation of three neuron projection development genes ARF4, KIF5B and RAB8A in the aganglionic part of the colon were verified in 15 paired colon samples using WB. The findings of this study will shed new light on the pathogenesis of HSCR and facilitate the development of therapeutic targets.




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Proteome Turnover in the Spotlight: Approaches, Applications & Perspectives [Review]

In all cells, proteins are continuously synthesized and degraded in order to maintain protein homeostasis and modify gene expression levels in response to stimuli. Collectively, the processes of protein synthesis and degradation are referred to as protein turnover. At steady state, protein turnover is constant to maintain protein homeostasis, but in dynamic responses, proteins change their rates of synthesis and degradation in order to adjust their proteomes to internal or external stimuli. Thus, probing the kinetics and dynamics of protein turnover lends insight into how cells regulate essential processes such as growth, differentiation, and stress response. Here we outline historical and current approaches to measuring the kinetics of protein turnover on a proteome-wide scale in both steady-state and dynamic systems, with an emphasis on metabolic tracing using stable-isotope-labeled amino acids. We highlight important considerations for designing proteome turnover experiments, key biological findings regarding the conserved principles of proteome turnover regulation, and future perspectives for both technological and biological investigation.




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A proteomic approach to understand the clinical significance of acute myeloid leukemia-derived extracellular vesicles reflecting essential characteristics of leukemia [Research]

Extracellular vesicle (EV) proteins from acute myeloid leukemia (AML) cell lines were analyzed using mass spectrometry. The analyses identified 2450 proteins, including 461 differentially expressed proteins (290 upregulated and 171 downregulated). CD53 and CD47 were upregulated and were selected as candidate biomarkers. The association between survival of patients with AML and the expression levels of CD53 and CD47 at diagnosis was analyzed using mRNA expression data from The Cancer Genome Atlas database. Patients with higher expression levels showed significantly inferior survival than those with lower expression levels. Enzyme-linked immunosorbent assay results of the expression levels of CD53 and CD47 from EVs in the bone marrow of patients with AML at diagnosis and at the time of complete remission with induction chemotherapy revealed that patients with downregulated CD53 and CD47 expression appeared to relapse less frequently. Network model analysis of EV proteins revealed several upregulated kinases, including LYN, CSNK2A1, SYK, CSK, and PTK2B. The potential cytotoxicity of several clinically applicable drugs that inhibit these kinases was tested in AML cell lines. The drugs lowered the viability of AML cells. The collective data suggest that AML-derived EVs could reflect essential leukemia biology.




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A potential role for the Gsdf-eEF1{alpha} complex in inhibiting germ cell proliferation: A protein-interaction analysis in medaka (Oryzias latipes) from a proteomics perspective [Research]

Gonadal soma-derived factor (gsdf) has been demonstrated to be essential for testicular differentiation in medaka (Oryzias latipes). To understand the protein dynamics of Gsdf in spermatogenesis regulation, we used a His-tag "pull-down" assay coupled with shotgun LC-MS/MS to identify a group of potential interacting partners for Gsdf, which included cytoplasmic dynein light chain 2, eukaryotic polypeptide elongation factor 1 alpha (eEF1α), and actin filaments in mature medaka testis. As for the interaction with TGFβ-dynein being critical for spermatogonial division in Drosophila melanogaster, the physical interactions of Gsdf-dynein and Gsdf-eEF1α were identified through a yeast 2-hybrid (Y2H) screening of an adult testis cDNA library using Gsdf as bait, which were verified by a paired Y2H assay. Co-immunoprecipitation of Gsdf and eEF1α was defined in adult testes as supporting the requirement of a Gsdf and eEF1α interaction in testis development. Proteomics analysis (data are available via ProteomeXchange with identifier PXD022153) and ultrastrutural observations showed that Gsdf deficiency activated eEF1α-mediated protein synthesis and ribosomal biogenesis, which in turn led to the differentiation of undifferentiated germ cells. Thus, our results provide a framework and new insight into the coordination of a Gsdf (TGFβ and eEF1α complex in the basic processes of germ cell proliferation, transcriptional and translational control of sexual RNA which may be fundamentally conserved across phyla during sexual differentiation.




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Plasma proteomic data can contain personally identifiable, sensitive information and incidental findings [Research]

The goal of clinical proteomics is to identify, quantify, and characterize proteins in body fluids or tissue to assist diagnosis, prognosis, and treatment of patients. In this way, it is similar to more mature omics technologies, such as genomics, that are increasingly applied in biomedicine. We argue that, similar to those fields, proteomics also faces ethical issues related to the kinds of information that is inherently obtained through sample measurement, although their acquisition was not the primary purpose. Specifically, we demonstrate the potential to identify individuals both by their characteristic, individual-specific protein levels and by variant peptides reporting on coding single nucleotide polymorphisms. Furthermore, it is in the nature of blood plasma proteomics profiling that it broadly reports on the health status of an individual – beyond the disease under investigation. Finally, we show that private and potentially sensitive information, such as ethnicity and pregnancy status, can increasingly be derived from proteomics data. Although this is potentially valuable not only to the individual, but also for biomedical research, it raises ethical questions similar to the incidental findings obtained through other omics technologies. We here introduce the necessity of - and argue for the desirability for - ethical and human rights-related issues to be discussed within the proteomics community. Those thoughts are more fully developed in our accompanying manuscript. Appreciation and discussion of ethical aspects of proteomic research will allow for deeper, better-informed, more diverse, and, most importantly, wiser guidelines for clinical proteomics.




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Tackling Illegal Wildlife Trade in Africa: Economic Incentives and Approaches

Tackling Illegal Wildlife Trade in Africa: Economic Incentives and Approaches Research paper sysadmin 5 October 2018

Combating illegal wildlife trade and further pursuing conservation-development models could help generate considerable economic benefits for African countries, while ensuring the long-term preservation of Africa’s wealth of natural capital.

Field scout recording desert black rhino data, Save the Rhino Trust, Palmwag, Torra Conservancy, Damaraland, Namibia. Photo: Mint Images/Frans Lanting/Getty Images.

Summary

  • The illegal wildlife trade (IWT) significantly impacts African economies by destroying and corroding natural, human and social capital stocks. This hinders the achievement of the Sustainable Development Goals (SDGs) and has an impact on national budgets. Illicit financial flows from IWT deny revenue to governments where legal wildlife product trade exists and perpetuate cash externalization. IWT diverts national budgets away from social or development programmes, increases insecurity and threatens vulnerable populations.
  • In expanding wildlife economies and pursuing conservation-driven development models, governments can protect their citizens, derive revenue from wildlife products, and establish world class tourism offerings. The illegal exploitation of wildlife is often due to a failure to enforce rights over those resources, where rights are unclearly defined or not fully exercised. Southern African countries have defined these rights in various ways, contributing to regional differences in conservation practices and the socio-economic benefits derived from wildlife resources. Combating IWT is an important step towards allowing legitimate business and communities to develop livelihoods that incentivize stewardship and connect people to conservation.
  • The Southern African Development Community (SADC) has several framework policies for the establishment of transfrontier conservation areas (TFCAs). These promote local stewardship across multiple land-use areas to conserve biodiversity and increase the welfare and socioeconomic development of rural communities. Private-sector partnerships also increase skills transfer, improve access to investment finance, and expand economic opportunities, including through the promotion of local procurement. The economic benefits of TFCAs extend beyond tourism.
  • The economic value of African ecosystems is often under-recognized because they remain unquantified, partly due to the lack of available data on the broader economic costs of IWT. Improved monitoring and evaluation with key performance indicators would help governments and citizens to appreciate the economic value of combating IWT.




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New Frontiers in Gender-responsive Governance: Five Years of the W20

New Frontiers in Gender-responsive Governance: Five Years of the W20 Research paper sysadmin 2 November 2018

After five years of the W20, women and gender equality remain at the margin of the G20. There is a real risk of the W20 representing a one-off territorial gain at a frontier that could easily be pushed back again.

A woman holds a female symbol model as workers take part in a rally to mark May Day, International Workers’ Day, in Istanbul, Turkey on 1 May 2016. Photo: Berk Ozkan/Anadolu Agency/Getty Images.

Summary

  • 2018 marks the fifth anniversary of the first grouping of the W20, the engagement group of the G20 that focuses on gender-inclusive economic growth and advocates for gender equality across the G20 agenda. Formally launched under the Turkish G20 presidency in 2015, the W20 is made up of women from business, international organizations, civil society, think-tanks and academia across the G20 member states.
  • This paper takes stock of the critical steps in the development of the W20 over the last five years, examining its background, rationale and foundations, and identifying the areas of economic governance where it has so far contributed the most – and those where more action is needed. The W20 has filled a gap, it but needs to carefully assess its coherence with the UN agencies, the private sector, the G7 and other G20 engagement groups.
  • The establishment of the W20 has contributed to defining new frontiers for economic governance and shifting the traditional approach from gender-neutral to gender-responsive. Whereas in 2013 gender in the G20 was considered a marginal issue better dealt with by ministers for equal opportunities, now gender equality and women’s economic empowerment are part of the mainstream economic dialogue. The next step is to ensure more structural and monitored policy reforms at the G20 level.
  • Already, the W20 can count among its achievements the ‘25 by 25’ female labour force participation commitment adopted at the G20’s Brisbane summit in 2014, and the Women Entrepreneurs Finance Initiative (We-Fi) and Business Women Leaders’ Taskforce, both agreed at the Hamburg summit in 2017.
  • The W20 is constrained in its policy impact by limited engagement with the finance track and a lack of consistent resourcing levels. Addressing these issues would strengthen its role as a credible player in shifting global economic governance while contributing to good gender-responsive domestic policies.
  • Progress on gender equality has been too slow and too peripheral to drive change in the relatively short term – over one generation, for example. G20 governments must therefore embrace active, credible policies to bring more women into the labour market, improve access to education and finance, close the pay gap, invest in social infrastructure – especially childcare and assistance for the elderly – and support female entrepreneurs. These domestic policies need to be internationally coordinated so that action and benefits can be widespread.
  • A feminist, inclusive agenda at the G20 level should highlight the current empirical evidence of women’s exclusion from the benefit of their economic activity, both in G20 members and beyond. The W20 should also focus on efforts to remedy the lack of women’s representation in G20 processes and in economic governance as a whole.




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Moscow Rules: What Drives Russia to Confront the West

Moscow Rules: What Drives Russia to Confront the West Book sysadmin 17 January 2019

Keir Giles surveys Russia’s history and the present day to explain why its current leadership feels it has no choice but to challenge and attack the West. Recognising and accepting that this will not change in the near future will help the West find a way of dealing with Russia without risking a deeper conflict.

This book is for anyone that cannot understand why Russia and its leaders behave as they do.

The relationship between Russia and the West is once again deep in crisis. A major reason is that Western leaders have too often believed or hoped that Russia sees the world as they do — but things look very different from Moscow. This book shows that efforts at engagement with Russia that do not take this into account are a key reason for repeated disappointment and crisis.

In confronting the West, Russia is implementing strategic and doctrinal approaches that have been consistent for centuries. The roots of current Russian behaviour and demands can be traced not just to the Soviet era, but back into Tsarist foreign and domestic policy, and further to the structure and rules of Russian society. But this also gives the US and the West pointers for how to behave — and how not to — in order to manage the challenge of Russia effectively, based on past experience of both successful and unsuccessful engagement with Moscow.

The book recognizes the reality of confrontation and provides an essential introduction to grasping why Russia sees it as inevitable. Consequently, it offers a basis for building a less crisis-prone relationship with Russia.

This book is part of the Insights series.

Praise for Moscow Rules

My only regret is that I did not have this book 35 years ago

Toomas Ilves, former President of Estonia

Should be required reading for all who deal with Western policy towards Russia

Roderic Lyne, former British Ambassador to Moscow

About the author

Keir Giles is a senior consulting fellow at Chatham House, the Royal Institute of International Affairs. He also works with the Conflict Studies Research Centre (CSRC), a group of subject matter experts in Eurasian security with a particular focus on the wide range of security challenges coming from Russia.

Purchase




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Innovative Financing for Humanitarian Energy Interventions

Innovative Financing for Humanitarian Energy Interventions Research paper sysadmin 28 February 2019

This paper explores the increase in resources and funding needed to improve the access of displaced people to modern and sustainable energy services.

SOLARKIOSK stall in Talek, Kenya on 17 May 2017. Photo: Getty Images

Summary

  • In settings that host displaced and refugee communities, energy can act as an enabler for improved healthcare, education and access to clean water. More efficient sources of energy can also save money that can be reinvested in life-saving interventions. A range of challenges exist that inhibit the uptake and effective management of cleaner energy solutions in displacement settings. These are magnified by a lack of available and appropriate funding.
  • The current funding gap is significant. In many cases, involving the private sector (both enterprises and investors) is viewed as a way to accelerate delivery of sustainable energy solutions, leverage additional capital, efficiency and expertise, and adopt more sustainable and market-based approaches.
  • Displacement settings are an extreme example of complex and unpredictable operating environments. Traditional approaches to the financing of energy access will not be supported by the risk/return characteristics of this market opportunity, so alternative structures are needed.
  • Such structures can include mechanisms such as grants, guarantees, ‘results-based financing’ and ‘impact bonds’. These blended financial instruments should aim to leverage first losses – whereby, in the case of default, the first loss is taken by the ‘impact-first’ investors, or guarantors, thereby fully or partially protecting ‘finance-first’ investors.
  • Given the specific constraints of displacement settings, any financing mechanisms at present are likely to fall between the categories of providing ‘more efficient aid’ and ‘more efficient aid through markets’. They are likely to constitute a transitional step from grant-making towards the use of commercial investment vehicles.
  • While a number of financial mechanisms could be applied to attract private-sector engagement, most remain theoretical, with few being implemented extensively or at scale. Where such financial mechanisms have already been used, access to relevant data is poor, especially in circumstances where the desired outcomes were not achieved.
  • The Moving Energy Initiative (MEI) completed feasibility work into the concept of an energy humanitarian fund and found that, while a need for this type of facility has emerged, it sits in a difficult position between energy access, climate and humanitarian funding sources. Key donors are needed to drive forward innovative financing vehicles and further testing of these mechanisms, in order to generate market data and evidence for further iterations and additional investments.




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Moving Energy Initiative Learning Briefs

Moving Energy Initiative Learning Briefs Research paper sysadmin 29 March 2019

Drawing on experiences from Phase II of the MEI in Burkina Faso, Kenya and Jordan, these learning briefs highlight MEI’s approach to innovation, engagement with the private-sector and host communities, and gender-sensitive energy projects. The four learning papers are intended for practitioners and policymakers working in the humanitarian sector and host-country governments.

A shelf of energy appliances in a shop in Kakuma Town, Kenya. Photo credit: Gabriela Flores

Findings from Phase I of the Moving Energy Initiative (MEI) in 2015, published in the Chatham House research paper Heat, Light and Power for Refugees: Saving Lives, Reducing Costs, highlight the negative impacts of limited sustainable energy provision on the security of displaced populations. The paper also identified some of the challenges for energy programmes in this sector, such as the lack of robust data on energy access and the priorities of refugee populations.

In Phase II of the MEI, Practical Action led detailed research into the energy needs of refugees in Burkina Faso and Kenya. Chatham House analysed data on global refugee energy use in displacement contexts and produced an interactive map. Energy 4 Impact explored sustainable funding options, private-sector contract models and non-wood cooking concessions. The market development and low-carbon energy initiatives in Burkina Faso, Jordan and Kenya were managed by Practical Action and Energy 4 Impact, with the support of local partners. These partners represented the MEI at multiple conferences and events to share findings and advocate for the inclusion of displaced people in the sustainable energy agenda.

Drawing on experiences from Phase II of the MEI in Burkina Faso, Kenya and Jordan, these learning briefs highlight MEI’s approach to innovation, engagement with the private-sector and host communities, and gender-sensitive energy projects. The four learning papers are intended for practitioners and policymakers working in the humanitarian sector and host-country governments.




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The Chatham House Sustainable Laboratories Initiative: Prior Assessment Tool

The Chatham House Sustainable Laboratories Initiative: Prior Assessment Tool Other resource sysadmin 14 June 2019

Laboratories are critical for supporting effective infectious disease surveillance and outbreak response. This tool is meant to help structure a conversation between funding partners and recipient countries on how to most effectively establish or repurpose laboratories in low-resource environments.

Copyright: Getty Images/ER Productions Limited

Introduction

Laboratories are critical for supporting effective infectious disease surveillance and outbreak response, and lack of adequate laboratory capacity is a global challenge. As part of global health security initiatives, cooperative threat reduction efforts and international development programmes, sophisticated laboratories have been provided to mitigate biological threats and bolster a country’s capacity for detection, diagnosis and storage of high-consequence pathogens. Very often, these use the assumptions, standards and templates applied in high-income countries. However, it can be difficult or even impossible to sustain these facilities in low-resource environments. There can sometimes be limited local technical capacity and capability, which can result in a high reliance on imported expertise, skills, equipment and other resources. Sustainability can therefore be hard to achieve. In addition, when a funding partner withdraws, the laboratories can become disused, foundering without the trained personnel and financial resources to sustain them.

To help address this situation, a proposal gaining increasing support internationally is to adopt an approach based on a local risk assessment, whereby laboratories are appropriately and optimally tailored to the local risks and to the resources available, both in the short and longer term, without compromising biosafety and biosecurity.

A Chatham House workshop was convened in Abuja, Nigeria, in 2018 to explore what West African countries would find most appropriate in terms of building laboratory capacity, what the main challenges have been so far, and what needs to be done to improve the sustainability of laboratories in the region. It emerged that there was a need for a more structured conversation between the funding partner and recipient country early in the process – prior to embarking on the detailed planning phase for the establishment or repurposing of a laboratory. This should involve careful consideration and an assessment of existing and planned capacity, needs and contextual issues, together with proposals for how to address the issues revealed, so that any ensuing laboratory demonstrably supports the national strategy and therefore flourishes.

The purpose of this tool

This tool aims to provide a structure for such a conversation. Developed in close collaboration with international experts and West African stakeholders, it seeks to increase local ownership and help partners ensure they have given due attention to all the relevant aspects, including risks and benefits, that need to be considered at an early stage. It should provide clarity on what is needed and improve the sustainability of any laboratory project that might result from the discussions. The tool can be applied when a new laboratory is being considered, or when an existing laboratory is to be repurposed or strengthened. It is also appropriate for use with public health, veterinary and environmental laboratories. Although the tool was developed in the context of high-consequence pathogens in Africa, it is anticipated that it will find global application.

It should support recipient countries to take stock of their capacities and capabilities, identify gaps, conduct an analysis of their needs and to develop the business case that can assist in seeking the necessary political and financial support for the laboratory. Meanwhile, it should facilitate the process of due diligence for the funding partner and provide a better understanding of what the recipient country perspective and realities are, and what the scale and nature of any investment might be.




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Delivering Sustainable Food and Land Use Systems: The Role of International Trade

Delivering Sustainable Food and Land Use Systems: The Role of International Trade Research paper sysadmin 20 September 2019

This paper explores a set of core trade-related issues affecting the food and land use system, and proposes constructive ways forward in reconfiguring the global trading system towards delivering a more sustainable and healthy diet for all.

Aerial view of containers sitting stacked at Qingdao Port in the Shandong province of China. Photo by Han Jiajun/Visual China Group via Getty Images.

  • Meeting future global food security requirements is not just about quantity; it is also about meeting growing needs in a way that safeguards human as well as planetary health. But national priorities and policies often remain out of sync with aspirations for more sustainable and healthy food systems.
  • International trade and trade policies play an ambiguous role in the current food system. With 80 per cent of the world’s population depending on imports to meet at least part of their food and nutritional requirements, trade has a unique function in offsetting imbalances between supply and demand. However, in the absence of effective regulatory frameworks or pricing frameworks that internalize environmental, social or health costs, trade can exacerbate and globalize challenges associated with food production and land use trends such as deforestation, land degradation, greenhouse gas emissions, biodiversity loss and the shift to unhealthy diets.
  • Over the last two decades, trade in agricultural products (excluding intra-EU flows) has more than tripled in value, to reach $1.33 trillion. The geography of global food trade flows has also shifted, primarily towards South–South trade, which now accounts for roughly a quarter of total agricultural trade flows. The nature of global trade has changed drastically, with traditional exports such as wheat and coffee growing slowly at around 2 per cent per year, while products such as palm oil, fruit juice, soft drinks and other processed products have grown at 8 per cent or more annually.
  • This overall increase in trade in agricultural products raises questions about the growing utilization of resources, such as water or soil nutrients, that are embedded in those products through production and processing. Trade itself also causes negative environmental impacts, starting with greenhouse gas emissions associated with transport and storage. If the environmental cost associated with production and trade is not reflected in the final price of goods, trade may accelerate the depletion of resources or their unsustainable use.
  • It is critical to ensure that trade policy options pursued by producing and consuming countries alike will support a transition to more sustainable and healthier food and land use systems. The first step in addressing trade-related food systems challenges must involve rebuilding trust among policy actors. There is a need for new spaces for informal dialogue among actors, and ‘soft’ governance mechanisms that can help rebuild consensus on the best ways forward. Meeting these challenges also requires an appreciation of the complex interactions between sectoral policies (e.g. on water, land, food, etc.) and their multiple interfaces with trade policies.
  • Conditioning the use of subsidies on their sustainability and/or health impacts encourages the delivery of essential public goods in ways that are consistent with sustainability and health goals. A first step therefore is the removal of perverse incentives (e.g. subsidies encouraging the overuse of fertilizers or pesticides or the overproduction of certain commodities, as well as certain biofuels subsidies) and replacing them with market-correcting subsidies.
  • Trade facilitation measures for fruits and vegetables that are aimed at easing transit at the border, by cutting unnecessary bureaucracy and reducing waiting times, can improve their availability, reduce costs and improve food quality and safety for consumers. Similarly, measures aimed at improving sustainable cold storage and upgrading value chains can support better diets and consumption by increasing the availability of fresh produce on markets, especially in developing countries.
  • A global food stamps programme developed through the G20 and facilitated by the UN’s food agencies could address purchasing power imbalances and tackle malnutrition in developing countries. If carefully designed, such ‘safety net’ schemes can not only contribute to improving calorific intakes but also help deliver more balanced and healthier diets. Careful attention must be given to how such a scheme would work in practice, building on experience to date with similar initiatives.
  • Integrating the notion of sustainable food and inputs trade in the post-2020 global biodiversity framework can help to deliver more sustainable and healthier food and land use systems. This could be achieved by likeminded countries introducing a set of goals or targets aimed at mitigating the role of trade in placing indirect pressure on biodiversity, and to encourage trade in biodiversity-based products including natural ingredients produced ethically and following sustainability principles and criteria.
  • An SDG-oriented agenda for agricultural trade is needed. It could be formed by countries seeking to remove perverse incentives, guaranteeing a safe harbour for market-correcting measures, clarifying existing rules and establishing plurilateral negotiations among subsets of the WTO membership, or sectoral approaches, to address specific challenges.
  • Greenhouse gas emissions resulting from trade need to be addressed. Governments could seek to achieve this through ensuring the carbon neutrality of existing and new trade deals, either by connecting carbon markets among contracting parties or by developing joint initiatives to tax international maritime and air transport emissions.




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AI-driven Personalization in Digital Media: Political and Societal Implications

AI-driven Personalization in Digital Media: Political and Societal Implications Research paper sysadmin 2 December 2019

The fallout from disinformation and online manipulation strategies have alerted Western democracies to the novel, nuanced vulnerabilities of our information society. This paper outlines the implications of the adoption of AI by the the legacy media, as well as by the new media, focusing on personalization.

The Reuters and other news apps seen on an iPhone, 29 January 2019. Photo: Getty Images.

Summary

  • Machine learning (ML)-driven personalization is fast expanding from social media to the wider information space, encompassing legacy media, multinational conglomerates and digital-native publishers: however, this is happening within a regulatory and oversight vacuum that needs to be addressed as a matter of urgency.
  • Mass-scale adoption of personalization in communication has serious implications for human rights, societal resilience and political security. Data protection, privacy and wrongful discrimination, as well as freedom of opinion and of expression, are some of the areas impacted by this technological transformation.
  • Artificial intelligence (AI) and its ML subset are novel technologies that demand novel ways of approaching oversight, monitoring and analysis. Policymakers, regulators, media professionals and engineers need to be able to conceptualize issues in an interdisciplinary way that is appropriate for sociotechnical systems.
  • Funding needs to be allocated to research into human–computer interaction in information environments, data infrastructure, technology market trends, and the broader impact of ML systems within the communication sector.
  • Although global, high-level ethical frameworks for AI are welcome, they are no substitute for domain- and context-specific codes of ethics. Legacy media and digital-native publishers need to overhaul their editorial codes to make them fit for purpose in a digital ecosystem transformed by ML. Journalistic principles need to be reformulated and refined in the current informational context in order to efficiently inform the ML models built for personalized communication.
  • Codes of ethics will not by themselves be enough, so current regulatory and legislative frameworks as they relate to media need to be reassessed. Media regulators need to develop their in-house capacity for thorough research and monitoring into ML systems, and – when appropriate –proportionate sanctions for actors found to be employing such systems towards malign ends. Collaboration with data protection authorities, competition authorities and national electoral commissions is paramount for preserving the integrity of elections and of a political discourse grounded on democratic principles.
  • Upskilling senior managers and editorial teams is fundamental if media professionals are to be able to engage meaningfully and effectively with data scientists and AI engineers.




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Centenary Series: Exploring the International Affairs Archive

Centenary Series: Exploring the International Affairs Archive dora.popova 14 September 2020

International Affairs has been a central part of the institute’s history, both as a record of speeches made by dignitaries such as Mahatma Gandhi and Henry Kissinger, and as a forum for policy-relevant academic research.

Delving into the International Affairs archive brings out stories behind some of the most significant players of the last century.




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Phosphorylation of SMURF2 by ATM exerts a negative feedback control of DNA damage response [DNA and Chromosomes]

Timely repair of DNA double-strand breaks (DSBs) is essential to maintaining genomic integrity and preventing illnesses induced by genetic abnormalities. We previously demonstrated that the E3 ubiquitin ligase SMURF2 plays a critical tumor suppressing role via its interaction with RNF20 (ring finger protein 20) in shaping chromatin landscape and preserving genomic stability. However, the mechanism that mobilizes SMURF2 in response to DNA damage remains unclear. Using biochemical approaches and MS analysis, we show that upon the onset of the DNA-damage response, SMURF2 becomes phosphorylated at Ser384 by ataxia telangiectasia mutated (ATM) serine/threonine kinase, and this phosphorylation is required for its interaction with RNF20. We demonstrate that a SMURF2 mutant with an S384A substitution has reduced capacity to ubiquitinate RNF20 while promoting Smad3 ubiquitination unabatedly. More importantly, mouse embryonic fibroblasts expressing the SMURF2 S384A mutant show a weakened ability to sustain the DSB response compared with those expressing WT SMURF2 following etoposide treatment. These data indicate that SMURF2-mediated RNF20 ubiquitination and degradation controlled by ataxia telangiectasia mutated–induced phosphorylation at Ser384 constitutes a negative feedback loop that regulates DSB repair.




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HIV: Breakthrough study raises hopes of effective prevention if drug’s cost can be lowered




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First mpox vaccines arrive in Africa as officials work “blindly” to contain outbreaks




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Boy who survived life support withdrawal confirms “medicine is a science of uncertainty,” says judge




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Whooping cough: Fivefold rise in US cases spells return to pre-pandemic levels




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Political Opposition and Policy Alternatives in Zambia

Political Opposition and Policy Alternatives in Zambia 31 October 2017 — 10:30AM TO 11:30AM Anonymous (not verified) 19 October 2017 Chatham House, London

In Zambia’s 2016 national election, the Patriotic Front (PF) was re-elected by a narrow margin. The PF’s Edgar Lungu secured 50.35 per cent of the vote according to the Electoral Commission of Zambia, narrowly avoiding a second round, while his main rival, Hakainde Hichilema, won 47.67 per cent. The UPND, led by Mr Hichilema, alleges electoral fraud and has challenged the result in the courts and through direct protests. Mr Hichilema was imprisoned for 100 days.

At this meeting, Hakainde Hichilema will discuss his UPND priorities, how to strengthen opposition parties and their role in Zambia’s democratic future.

Read transcript




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Angola Forum 2018: 30th Anniversary of the Battle of Cuito Cuanavale

Angola Forum 2018: 30th Anniversary of the Battle of Cuito Cuanavale 23 March 2018 — 10:00AM TO 2:30PM Anonymous (not verified) 8 March 2018 Chatham House, London

Reflections on Southern Africa’s Turning Point

23 March 2018 marks the 30th anniversary of the final assault of what became known as the Battle of Cuito Cuanavale.

The confrontation between the Angolan army, supported by Cuba and the Soviet Union, and the armed opposition UNITA, supported by the South African Defence Force, is the largest land battle to have taken place in Africa since World War Two.

The battle was a watershed in Angolan and southern African history, but its significance continues to be contested. Today, although the battlefield has a monument and museum, it remains one of the most landmine-contaminated parts of Angola and this hinders development plans for international tourism.

This event brings together veterans and experts to contribute towards developing a deeper understanding of the battle. Discussions will further focus on the significance of the wider events around the battle, its regional implications, as well as the legacy of the battlefield.




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Public Service, Accountability and Delivery in Malawi

Public Service, Accountability and Delivery in Malawi 17 October 2018 — 12:00PM TO 1:00PM Anonymous (not verified) 11 October 2018 Chatham House, London

On 21 May 2019, Malawi will hold presidential, parliamentary and local ward elections. Public concerns of periodic food shortages and power outages, together with continuing fiscal uncertainty amidst spiralling public debt, bring added significance to this electoral process and beyond as well as significant pressures on the next government. Vice President Saulos Chilima‘s decision to form a new party, the United Transformation Party (UTM), as well as the return of former president Joyce Banda to mainstream politics, mean that with such issues at stake, and political discourse dominated by allegations of corruption, Malawi’s leaders across the spectrum will need clear policy focus to address the country’s significant challenges and meet citizens’ needs.
Vice President Chilima will discuss the formation of the UTM and how to foster intra-party democracy. He will present its approach to poverty reduction, addressing economic instability and challenges ahead of next year’s elections.
THIS EVENT IS NOW FULL AND REGISTRATION HAS CLOSED.




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Zimbabwe Futures 2030: A Vision for Inclusive Long-Term Economic Recovery

Zimbabwe Futures 2030: A Vision for Inclusive Long-Term Economic Recovery 10 October 2019 — 10:00AM TO 12:15PM Anonymous (not verified) 5 September 2019 Harare, Zimbabwe

In its Vision 2030, the government of Zimbabwe committed itself to facilitating an open market and stable economy through strategies such as the Transitional Stabilization Programme (TSP) and new industrialization policy. The private sector is pivotal to these objectives and creating an environment conducive to inclusive and job-creating economic growth. Economic growth can only be achieved with a conducive policy environment and government support to underpin markets with provision of public goods, entrepreneurial incentives and protect contract enforcement and dispute resolution mechanisms.

This event will launch a new Chatham House Africa Programme publication on Zimbabwe’s Vision 2030. The paper is the culmination of an inclusive research process that has drawn on senior private sector expertise, civil society, academics, technocratic elements of government and other experts to develop policy recommendations that will support inclusive economic growth in Zimbabwe.

This event is held in partnership with the Zimbabwe Business Club and Konrad Adenauer Stiftung (KAS). It is supported by KAS and the Dulverton Trust.




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Lords recommend “passive immunisation” if bird flu reaches UK




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Endovascular treatment for acute ischaemic stroke in routine clinical practice: prospective, observational cohort study (MR CLEAN Registry)




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David Oliver: What the plan for social care omitted




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Challenges in diabetes and obesity: five minutes with . . . Jonathan Valabhji




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Artificial pancreases for type 1 diabetes: Better access is “watershed moment”—but delivery is key




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Helen Salisbury: GP collective action to end unfunded work




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Diabetes: Once weekly insulin could be as effective as daily injections, studies indicate




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Black perspectives on international relations

Black perspectives on international relations 27 October 2022 — 5:00PM TO 6:00PM Anonymous (not verified) 4 October 2022 Chatham House and Online

How can black perspectives help the world tackle global challenges and expand our understanding of international relations?

As social boundaries change, the viewpoints of black academics, thought leaders and policymakers have grown in both influence and strength worldwide, challenging western and institutional norms. 

However, many institutions and organizations, long established with the exclusion of black voices, have to adapt if there is to be greater inclusion and diversity of thought when tackling major global issues.

Growing reflection on the legacy of colonialism and the importance of the power of diversity may be needed for today’s problems.

The search for global racial equality has seen a growing commitment to ensuring the black experience is at the heart of geopolitical discussions.

This panel discussion looks at what changes are occurring now and how is the conversation shifting. It also examines the challenges posed by the increasing politicization of race and culture issues in the current political environment.

Key questions discussed by the panel include:

  • What is the importance of black voices in international relations and where are the main challenges to greater incorporation?

  • What are some of the leading perspectives, approaches and beliefs within Africa and across the black diaspora regarding international relations?

  • To what extent are governments, businesses and leading global institutions making efforts to include more black voices in decision-making?

  • How are black academics changing wider geopolitical conversations and to what extent can deeper conversations lead to change?

  • Will an ‘African Century’ bring black perspectives on international relations to the fore of the geopolitical agenda?

As with all members events, questions from the audience drive the conversation.

Read the transcript.