ac Thermal proteome profiling in zebrafish reveals effects of napabucasin on retinoic acid metabolism [Research] By www.mcponline.org Published On :: 2020-10-28T08:35:46-07:00 Thermal proteome profiling (TPP) allows for the unbiased detection of drug – target protein engagements in vivo. Traditionally, one cell type is used for TPP studies, with the risk of missing important differentially expressed target proteins. The use of whole organisms would circumvent this problem. Zebrafish embryos are amenable to such an approach. Here, we used TPP on whole zebrafish embryo lysate to identify protein targets of napabucasin, a compound that may affect Signal transducer and activator of transcription 3 (Stat3) signaling through an ill-understood mechanism. In zebrafish embryos, napabucasin induced developmental defects consistent with inhibition of Stat3 signaling. TPP profiling showed no distinct shift in Stat3 upon napabucasin treatment, but effects were detected on the oxidoreductase, Pora, which might explain effects on Stat3 signaling. Interestingly, thermal stability of several aldehyde dehydrogenases (Aldhs) was affected. Moreover, napabucasin activated ALDH enzymatic activity in vitro. Aldhs have crucial roles in retinoic acid metabolism and functionally we validated napabucasin-mediated activation of the retinoic acid pathway in zebrafish in vivo. We conclude that TPP profiling in whole zebrafish embryo lysate is feasible and facilitates direct correlation of in vivo effects of small molecule drugs with their protein targets. Full Article
ac Isolation of acetylated and unmodified protein N-terminal peptides by strong cation exchange chromatographic separation of TrypN-digested peptides [Technological Innovation and Resources] By www.mcponline.org Published On :: 2020-11-02T12:35:15-08:00 We developed a simple and rapid method to enrich protein N-terminal peptides, in which the protease TrypN is first employed to generate protein N-terminal peptides without Lys or Arg and internal peptides with two positive charges at their N-termini, and then the N-terminal peptides with or without N-acetylation are separated from the internal peptides by strong cation exchange chromatography according to a retention model based on the charge/orientation of peptides. This approach was applied to 20 μg of human HEK293T cell lysate proteins to profile the N-terminal proteome. On average, 1,550 acetylated and 200 unmodified protein N-terminal peptides were successfully identified in a single LC/MS/MS run with less than 3% contamination with internal peptides, even when we accepted only canonical protein N-termini registered in the Swiss-Prot database. Since this method involves only two steps, protein digestion and chromatographic separation, without the need for tedious chemical reactions, it should be useful for comprehensive profiling of protein N-termini, including proteoforms with neo-N-termini. Full Article
ac Protein modification characteristics of the malaria parasite Plasmodium falciparum and the infected erythrocytes [Research] By www.mcponline.org Published On :: 2020-11-04T10:35:17-08:00 Malaria elimination is still pending on the development of novel tools that rely on a deep understanding of parasite biology. Proteins of all living cells undergo a myriad number of posttranslational modifications (PTMs) that are critical to multifarious life processes. An extensive proteome-wide dissection revealed a fine PTM map of most proteins in both Plasmodium falciparum, the causative agent of severe malaria, and the infected red blood cells. More than two-thirds of proteins of the parasite and its host cell underwent extensive and dynamic modification throughout the erythrocytic developmental stage. PTMs critically modulate the virulence factors involved in the host-parasite interaction and pathogenesis. Furthermore, P. falciparum stabilized the supporting proteins of erythrocyte origin by selective de-modification. Collectively, our multiple omic analyses, apart from having furthered a deep understanding of the systems biology of P. falciparum and malaria pathogenesis, provide a valuable resource for mining new antimalarial targets. Full Article
ac Accelerating the field of epigenetic histone modification through mass spectrometry-based approaches [Review] By www.mcponline.org Published On :: 2020-11-17T10:35:13-08:00 Histone post-translational modifications (PTMs) are one of the main mechanisms of epigenetic regulation. Dysregulation of histone PTMs leads to many human diseases, such as cancer. Due to its high-throughput, accuracy, and flexibility, mass spectrometry (MS) has emerged as a powerful tool in the epigenetic histone modification field, allowing the comprehensive and unbiased analysis of histone PTMs and chromatin-associated factors. Coupled with various techniques from molecular biology, biochemistry, chemical biology and biophysics, MS has been employed to characterize distinct aspects of histone PTMs in the epigenetic regulation of chromatin functions. In this review we will describe advancements in the field of MS that have facilitated the analysis of histone PTMs and chromatin biology. Full Article
ac Thyroglobulin interactome profiling defines altered proteostasis topology associated with thyroid dyshormonogenesis [Research] By www.mcponline.org Published On :: 2020-11-18T11:35:14-08:00 Thyroglobulin (Tg) is a secreted iodoglycoprotein serving as the precursor for T3 and T4 hormones. Many characterized Tg gene mutations produce secretion-defective variants resulting in congenital hypothyroidism (CH). Tg processing and secretion is controlled by extensive interactions with chaperone, trafficking, and degradation factors comprising the secretory proteostasis network. While dependencies on individual proteostasis network components are known, the integration of proteostasis pathways mediating Tg protein quality control and the molecular basis of mutant Tg misprocessing remain poorly understood. We employ a multiplexed quantitative affinity purification–mass spectrometry approach to define the Tg proteostasis interactome and changes between WT and several CH-variants. Mutant Tg processing is associated with common imbalances in proteostasis engagement including increased chaperoning, oxidative folding, and engagement by targeting factors for ER-associated degradation (ERAD). Furthermore, we reveal mutation-specific changes in engagement with N-glycosylation components, suggesting distinct requirements for one Tg variant on dual engagement of both oligosaccharyltransferase complex isoforms for degradation. Modulating dysregulated proteostasis components and pathways may serve as a therapeutic strategy to restore Tg secretion and thyroid hormone biosynthesis. Full Article
ac Proteogenomic characterization of the pathogenic fungus Aspergillus flavus reveals novel genes involved in aflatoxin production [Research] By www.mcponline.org Published On :: 2020-11-24T17:35:19-08:00 Aspergillus flavus (A. flavus), a pathogenic fungus, can produce carcinogenic and toxic aflatoxins that are a serious agricultural and medical threat worldwide. Attempts to decipher the aflatoxin biosynthetic pathway have been hampered by the lack of a high-quality genome annotation for A. flavus. To address this gap, we performed a comprehensive proteogenomic analysis using high-accuracy mass spectrometry data for this pathogen. The resulting high-quality dataset confirmed the translation of 8,724 previously-predicted genes, and identified 732 novel proteins, 269 splice variants, 447 single amino acid variants, 188 revised genes. A subset of novel proteins was experimentally validated by RT-PCR and synthetic peptides. Further functional annotation suggested that a number of the identified novel proteins may play roles in aflatoxin biosynthesis and stress responses in A. flavus. This comprehensive strategy also identified a wide range of post-translational modifications (PTMs), including 3,461 modification sites from 1,765 proteins. Functional analysis suggested the involvement of these modified proteins in the regulation of cellular metabolic and aflatoxin biosynthetic pathways. Together, we provided a high quality annotation of A. flavus genome and revealed novel insights into the mechanisms of aflatoxin production and pathogenicity in this pathogen. Full Article
ac Proteome Turnover in the Spotlight: Approaches, Applications & Perspectives [Review] By www.mcponline.org Published On :: 2020-11-30T16:35:18-08:00 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. Full Article
ac Proteomic analyses identify differentially expressed proteins and pathways between low-risk and high-risk subtypes of early-stage lung adenocarcinoma and their prognostic impacts [Research] By www.mcponline.org Published On :: 2020-11-30T14:35:18-08:00 The histopathological subtype of lung adenocarcinoma (LUAD) is closely associated with prognosis. Micropapillary or solid predominant LUAD tends to relapse after surgery at an early stage, whereas lepidic pattern shows a favorable outcome. However, the molecular mechanism underlying this phenomenon remains unknown. Here, we recruited 31 lepidic predominant LUADs (LR: low-risk subtype group) and 28 micropapillary or solid predominant LUADs (HR: high-risk subtype group). Tissues of these cases were obtained and label-free quantitative proteomic and bioinformatic analyses were performed. Additionally, prognostic impact of targeted proteins was validated using The Cancer Genome Atlas databases (n=492) and tissue microarrays composed of early-stage LUADs (n=228). A total of 192 differentially expressed proteins were identified between tumor tissues of LR and HR and three clusters were identified via hierarchical clustering excluding eight proteins. Cluster 1 (65 proteins) showed a sequential decrease in expression from normal tissues to tumor tissues of LR and then to HR and was predominantly enriched in pathways such as tyrosine metabolism and ECM-receptor interaction, and increased matched mRNA expression of 18 proteins from this cluster predicted favorable prognosis. Cluster 2 (70 proteins) demonstrated a sequential increase in expression from normal tissues to tumor tissues of LR and then to HR and was mainly enriched in pathways such as extracellular organization, DNA replication and cell cycle, and high matched mRNA expression of 25 proteins indicated poor prognosis. Cluster 3 (49 proteins) showed high expression only in LR, with high matched mRNA expression of 20 proteins in this cluster indicating favorable prognosis. Furthermore, high expression of ERO1A and FEN1 at protein level predicted poor prognosis in early-stage LUAD, supporting the mRNA results. In conclusion, we discovered key differentially expressed proteins and pathways between low-risk and high-risk subtypes of early-stage LUAD. Some of these proteins could serve as potential biomarkers in prognostic evaluation. Full Article
ac A proteomic approach to understand the clinical significance of acute myeloid leukemia-derived extracellular vesicles reflecting essential characteristics of leukemia [Research] By www.mcponline.org Published On :: 2020-11-30T16:35:18-08:00 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. Full Article
ac The Mechanism of NEDD8 Activation of CUL5 Ubiquitin E3 Ligases [Research] By www.mcponline.org Published On :: 2020-12-02T10:35:15-08:00 Cullin RING E3 Ligases (CRLs) ubiquitylate hundreds of important cellular substrates. Here we have assembled and purified the Ankyrin repeat and SOCS Box protein 9 CUL5 RBX2 Ligase (ASB9-CRL) in vitro and show how it ubiquitylates one of its substrates, CKB. CRLs occasionally collaborate with RING between RING E3 ligases (RBRLs) and indeed, mass spectrometry analysis showed that CKB is specifically ubiquitylated by the ASB9-CRL-ARIH2-UBE2L3 complex. Addition of other E2s such as UBE2R1 or UBE2D2 contribute to polyubiquitylation but do not alter the sites of CKB ubiquitylation. Hydrogen-deuterium exchange mass spectrometry (HDX-MS) analysis revealed that CUL5 neddylation allosterically exposes its ARIH2 binding site, promoting high affinity binding, and it also sequesters the NEDD8 E2 (UBE2F) binding site on RBX2. Once bound, ARIH2 helices near the Ariadne domain active site are exposed, presumably relieving its autoinhibition. These results allow us to propose a model of how neddylation activates ASB-CRLs to ubiquitylate their substrates. Full Article
ac The peptide vaccine of the future [Review] By www.mcponline.org Published On :: 2020-12-07T10:40:19-08:00 The approach of peptide-based anti-cancer vaccination has proven the ability to induce cancer-specific immune responses in multiple studies for various cancer entities. However, clinical responses remain so far limited to single patients and broad clinical applicability was not achieved. Therefore, further efforts are required to improve peptide vaccination in order to integrate this low side effect therapy into the clinical routine of cancer therapy. To design clinically effective peptide vaccines in the future, different issues have to be addressed and optimized comprising antigen target selection as well as choice of optimal adjuvants and vaccination schedules. Furthermore, the combination of peptide-based vaccines with other immuno- and molecular targeted therapies as well as the development of predictive biomarkers could further improve efficacy. In this review, current approaches in the development of peptide-based vaccines and critical implications for optimal vaccine design are discussed. Full Article
ac 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] By www.mcponline.org Published On :: 2020-12-08T12:35:19-08:00 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. Full Article
ac In depth characterization of the Staphylococcus aureus phosphoproteome reveals new targets of Stk1 [Research] By www.mcponline.org Published On :: 2020-12-17T07:31:07-08:00 Staphylococcus aureus is a major cause of infections worldwide and infection results in a variety of diseases. As of no surprise, protein phosphorylation is an important game player in signaling cascades and has been shown to be involved in S. aureus virulence. Albeit long neglected, eukaryotic-type serine/threonine kinases in S. aureus have been implicated in this complex signaling cascades. Due to the sub-stoichiometric nature of protein phosphorylation and a lack of suitable analysis tools, the knowledge of these cascades is however, to date, still limited.Here, were apply an optimized protocol for efficient phosphopeptide enrichment via Fe3+-IMAC followed by LC-MS/MS to get a better understanding of the impact of protein phosphorylation on the complex signaling networks involved in pathogenicity. By profiling a serine/threonine kinase and phosphatase mutant from a methicillin-resistant S. aureus mutant library, we generated the most comprehensive phosphoproteome dataset of S. aureus to date, aiding a better understanding of signaling in bacteria. With the identification of 3800 class I p-sites we were able to increase the number of identifications by more than 21 times compared to recent literature. In addition, we were able to identify 74 downstream targets of the only reported eukaryotic-type Ser/Thr kinase of the S. aureus strain USA300, Stk1. This work allowed an extensive analysis of the bacterial phosphoproteome and indicates that Ser/Thr kinase signaling is far more abundant than previously anticipated in S. aureus. Full Article
ac Multi-sample mass spectrometry-based approach for discovering injury markers in chronic kidney disease [Research] By www.mcponline.org Published On :: 2020-12-20T09:35:16-08:00 Urinary proteomics studies have primarily focused on identifying markers of chronic kidney disease (CKD) progression. Here, we aimed to determine urinary markers of CKD renal parenchymal injury through proteomics analysis in animal kidney tissues and cells and in the urine of patients with CKD. Label-free quantitative proteomics analysis based on liquid chromatography-tandem mass spectrometry was performed on urine samples obtained from 6 normal controls and 9, 11, and 10 patients with CKD stages 1, 3, and 5, respectively, and on kidney tissue samples from a rat CKD model by 5/6 nephrectomy. Tandem mass tag-based quantitative proteomics analysis was performed for primary cultured glomerular endothelial cells (GECs) and proximal tubular epithelial cells (PTECs) before and after inducing 24-h hypoxia injury. Upon hierarchical clustering, out of 858 differentially expressed proteins (DEPs) in the urine of CKD patients, the levels of 416 decreased and 403 increased sequentially according to the disease stage, respectively. Among 2965 DEPs across 5/6 nephrectomized and sham-operated rat kidney tissues, 86 DEPs showed same expression patterns in the urine and kidney tissue. After cross-validation with two external animal proteome datasets, 38 DEPs were organized; only 10 DEPs, including serotransferrin, gelsolin, poly ADP-ribose polymerase 1, neuroblast differentiation-associated protein AHNAK, microtubule-associated protein 4, galectin-1, protein S, thymosin beta-4, myristoylated alanine-rich C-kinase substrate, and vimentin were finalized by screening human GECs and PTECs data. Among these ten potential candidates for universal CKD marker, validation analyses for protein S and galectin-1 were conducted. Galectin-1 was observed to have a significant inverse correlation with renal function as well as higher expression in glomerulus with chronic injury than protein S. This constitutes the first multi-sample proteomics study for identifying key renal-expressed proteins associated with CKD progression. The discovered proteins represent potential markers of chronic renal cell and tissue damage and candidate contributors to CKD pathophysiology. Full Article
ac Systematic identification of P. falciparum sporozoite membrane protein interactions reveals an essential role for the p24 complex in host infection [Research] By www.mcponline.org Published On :: 2020-12-22T08:35:40-08:00 Sporozoites are a motile form of malaria-causing Plasmodium falciparum parasites that migrate from the site of transmission in the dermis through the bloodstream to invade hepatocytes. Sporozoites interact with many cells within the host, but the molecular identity of these interactions and their role in the pathology of malaria is poorly understood. Parasite proteins that are secreted and embedded within membranes are known to be important for these interactions, but our understanding of how they interact with each other to form functional complexes is largely unknown. Here, we compile a library of recombinant proteins representing the repertoire of cell surface and secreted proteins from the P. falciparum sporozoite and use an assay designed to detect extracellular interactions to systematically identify complexes. We identify three protein complexes including an interaction between two components of the p24 complex that is involved in the trafficking of glycosylphosphatidylinositol (GPI)-anchored proteins through the secretory pathway. Plasmodium parasites lacking either gene are strongly inhibited in the establishment of liver stage infections. These findings reveal an important role for the p24 complex in malaria pathogenesis and show that the library of recombinant proteins represents a valuable resource to investigate P. falciparum sporozoite biology. Full Article
ac CMMB (Carboxylate Modified Magnetic Bead) -based isopropanol gradient peptide fractionation (CIF) enables rapid and robust off-line peptide mixture fractionation in bottom-up proteomics [Research] By www.mcponline.org Published On :: 2020-12-22T08:35:40-08:00 Deep proteome coverage in bottom-up proteomics requires peptide-level fractionation to simplify the complex peptide mixture before analysis by tandem mass spectrometry. By decreasing the number of co-eluting precursor peptide ions, fractionation effectively reduces the complexity of the sample leading to higher sample coverage and reduced bias towards high abundance precursors that are preferentially identified in data-dependent acquisition strategies. To achieve this goal, we report a bead-based off-line peptide fractionation method termed CIF or Carboxylate modified magnetic bead-based isopropanol gradient peptide fractionation. CIF is an extension of the SP3 (single-pot solid-phase-enhanced sample preparation) strategy and provides an effective but complementary approach to other commonly used fractionation methods including strong cation exchange (SCX) and reversed phase (RP)-based chromatography. We demonstrate that CIF is an effective offline separation strategy capable of increasing the depth of peptide analyte coverage both when used alone or as a second dimension of peptide fractionation in conjunction with high pH RP. These features make it ideally suited for a wide range of proteomic applications including the affinity purification of low abundance bait proteins. Full Article
ac The role of Data-Independent Acquisition for Glycoproteomics [Review] By www.mcponline.org Published On :: 2020-12-28T12:35:13-08:00 Data independent acquisition (DIA) is now an emerging method in bottom-up proteomics and capable of achieving deep proteome coverage and accurate label-free quantification. However, for post-translational modifications (PTM), such as glycosylation, DIA methodology is still in the early stage of development. The full characterization of glycoproteins requires site specific glycan identification as well as subsequent quantification of glycan structures at each site. The tremendous complexity of glycosylation represents a significant analytical challenge in glycoproteomics. This review focuses on the development and perspectives of DIA methodology for N- and O- glycoproteomics and posits that DIA-based glycoproteomics could be a method of choice to address some of the challenging aspects of glycoproteomics. First, the current challenges in glycoproteomics and the basic principles of DIA is briefly introduced. DIA based glycoproteomics is then summarized and described into four aspects based on the actual samples. Lastly, we discussed the important challenges and future perspectives in the field. We believe that DIA can significantly facilitate glycoproteomic studies and contribute to the development of future advanced tools and approaches in the field of glycoproteomics. Full Article
ac Unraveling the MAX2 Protein Network in Arabidopsis thaliana: Identification of the Protein Phosphatase PAPP5 as a Novel MAX2 Interactor [Research] By www.mcponline.org Published On :: 2020-12-28T07:35:13-08:00 The F-box protein MORE AXILLARY GROWTH 2 (MAX2) is a central component in the signaling cascade of strigolactones (SLs) as well as of the smoke derived karrikins (KARs) and the so far unknown endogenous KAI2 ligand (KL). The two groups of molecules are involved in overlapping and unique developmental processes, and signal-specific outcomes are attributed to perception by the paralogous α/β-hydrolases DWARF14 (D14) for SL and KARRIKIN INSENSITIVE 2/ HYPOSENSITIVE TO LIGHT (KAI2/HTL) for KAR/KL. Additionally, depending on which receptor is activated, specific members of the SUPPRESSOR OF MAX2 1 (SMAX1) – LIKE (SMXL) family control KAR/KL and SL responses. As proteins that function in the same signal transduction pathway often occur in large protein complexes, we aimed at discovering new players of the MAX2, D14 and KAI2 protein network by tandem affinity purification using Arabidopsis cell cultures. When using MAX2 as a bait, various proteins were co-purified among which general components of the Skp1-Cullin-F-box complex and members of the CONSTITUTIVE PHOTOMORPHOGENIC 9 signalosome. Here, we report the identification of a novel interactor of MAX2, a type 5 serine/threonine protein phosphatase, designated PHYTOCHROME-ASSOCIATED PROTEIN PHOSPHATASE 5 (PAPP5). Quantitative affinity purification pointed at PAPP5 as being more present in KAI2 rather than D14 protein complexes. In agreement, mutant analysis suggests that PAPP5 modulates KAR/KL-dependent seed germination in suboptimal conditions and seedling development. Additionally, a phosphopeptide enrichment experiment revealed that PAPP5 might dephosphorylate MAX2 in vivo independently of the synthetic strigolactone analog, rac-GR24. Together, by analyzing the protein complexes to which MAX2, D14 and KAI2 belong, we revealed a new MAX2 interactor, PAPP5, that might act through dephosphorylation of MAX2 to control mainly KAR/KL- related phenotypes and, hence, provide another link with the light pathway. Full Article
ac High-throughput and site-specific N-glycosylation analysis of human alpha-1-acid glycoprotein offers a great potential for new biomarker discovery [Research] By www.mcponline.org Published On :: 2020-12-29T12:35:15-08:00 Alpha-1-acid glycoprotein (AGP) is an acute phase glycoprotein in blood, which is primarily synthetized in the liver and whose biological role is not completely understood. It consists of 45% carbohydrates that are present in the form of five N-linked complex glycans. AGP N-glycosylation was shown to be changed in many different diseases and some changes appear to be disease-specific, thus it has a great diagnostic and prognostic potential. However, AGP glycosylation was mainly analyzed in small cohorts and without detailed site-specific glycan information. Here, we developed a cost-effective method for a high-throughput and site-specific N-glycosylation LC-MS analysis of AGP which can be applied on large cohorts, aid in search for novel disease biomarkers and enable better understanding of AGP’s role and function in health and disease. The method does not require isolation of AGP with antibodies and affinity chromatography, but AGP is enriched by acid precipitation from 5 μl of bloodplasma in a 96 well format. After trypsinization, AGP glycopeptides are purified using a hydrophilic interaction chromatography based solid-phase extraction and analyzed by RP-LC-ESI-MS. We used our method to show for the first time that AGP N-glycan profile is stable in healthy individuals (14 individuals in 3 time points), which is a requirement for evaluation of its diagnostic potential. Furthermore, we tested our method on a population including individuals with registered hyperglycemia in critical illness (59 cases and 49 controls), which represents a significantly increased risk of developing type 2 diabetes. Individuals at higher risk of diabetes presented increased N-glycan branching on AGP’s second glycosylation site and lower sialylation of N-glycans on AGP’s third and AGP1’s fourth glycosylation site. Although this should be confirmed on a larger prospective cohort, it indicates that site-specific AGP N-glycan profile could help distinguish individuals who are at risk of type 2 diabetes. Full Article
ac Global lysine acetylation and 2-hydroxyisobutyrylation reveal the metabolism conversion mechanism in Giardia lamblia [Research] By www.mcponline.org Published On :: 2020-12-29T13:35:14-08:00 Giardia lamblia (G. lamblia) disease is a zoonosis with a-infection rate affecting the general population of the world. Despite the constant possibility of damage due to their own metabolism, G. lamblia have survived and evolved to adapt to various environments. However, research on energy-metabolism conversion in G. lamblia is limited. This study aimed to reveal the dynamic metabolism-conversion mechanism in G. lamblia under sugar starvation by detecting global lysine acetylation and 2-hydroxyisobutyrylation sites combined with quantitative proteome analyses. A total of 2999 acetylation sites on 956 proteins and 8877 2-hydroxyisobutyryl sites on 1546 proteins were quantified under sugar starvation. Integrated Kac and Khib data revealed that modified proteins were associated with arginine biosynthesis, glycolysis/gluconeogenesis, and alanine, aspartate, and glutamate metabolism. These findings suggested that lysine acetylation and 2-hydroxyisobutyrylation were ubiquitous and provided deep insight into the metabolism-conversion mechanism in G. lamblia under sugar starvation. Overall, these results can help understand the biology of G. lamblia infections and reveal the evolution rule from prokaryote to eukaryote. Full Article
ac Tackling Illegal Wildlife Trade in Africa: Economic Incentives and Approaches By www.chathamhouse.org Published On :: Fri, 05 Oct 2018 15:21:13 +0000 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. 2018-10-11-tackling-illegal-wildlife-trade-africa-vandome-vines-final2 (PDF) Full Article
ac The Role of Sub-state and Non-state Actors in International Climate Processes: Civil Society By www.chathamhouse.org Published On :: Tue, 27 Nov 2018 09:59:58 +0000 The Role of Sub-state and Non-state Actors in International Climate Processes: Civil Society Research paper sysadmin 27 November 2018 Given today’s challenging geopolitical conditions and the evolving nature of the international climate regime since Paris, civil society must now once again recalibrate its strategies to ensure continued and increasing relevance. — Photo by The Climate Reality Project, ‘People’s Climate March Protest’, via Unsplash, 2017. This is one of four background papers feeding into a synthesis paper entitled The Role of Sub-state and Non-state Actors in International Climate Processes. Summary Following the failure of the 15th Conference of the Parties (COP 15) in Copenhagen in 2009, there was a step change in the sophistication and unity of civil society engagement on climate policy. This ensured that, subsequently, civil society was more effective in exercising multiple channels of influence around the negotiations for the Paris Agreement in 2015. Civil society proved to be particularly effective at harnessing the twin narratives of climate science and economics, and at leveraging an emerging multi-level governance architecture, to create political space for climate leadership. Given today’s challenging geopolitical conditions and the evolving nature of the international climate regime since Paris, civil society must now once again recalibrate its strategies to ensure continued and increasing relevance. In particular, the shift to a more ‘nationally grounded’ implementation regime focusing on individual states’ climate commitments will require civil society to become more effective at influencing domestic politics. At the same time, civil society will need to continue to seek strategic synergies at the international level. Civil society has a central role to play in ensuring that the first key test of the Paris ‘ratchet’ mechanism – revising countries’ pledged climate actions, or Nationally Determined Contributions (NDCs), by 2020 – is robust, science-informed and strongly rooted in domestic politics. 2018-11-28-non-state-actors-climate-civil-society-guy (PDF) Full Article
ac The Role of Sub-state and Non-state Actors in International Climate Processes: Corporate Sector By www.chathamhouse.org Published On :: Tue, 27 Nov 2018 10:09:06 +0000 The Role of Sub-state and Non-state Actors in International Climate Processes: Corporate Sector Research paper sysadmin 27 November 2018 Given the challenging political contexts since 2015, the corporate sector will have a key role to play in persuading national governments how technologies and expertise have moved on since the pledges were made. — Photo by Priscilla Du Preez, ‘Climate Reality’ via Unsplash, 2017. This is one of four background papers feeding into a synthesis paper entitled The Role of Sub-state and Non-state Actors in International Climate Processes. Summary The corporate sector has traditionally engaged governments at national rather than international level in lobbying for action related to climate change. Where it has engaged at an international level, this has often been to restrain regulation and ambition, such as in air transport. Over time, many businesses have increasingly understood that there is more commercial opportunity in a strong, consistent approach to tackling climate mitigation and adaptation, and an increasing number are willing to speak up on the issue. The Paris Climate Conference in 2015 demonstrated this positive engagement. Businesses are more powerful when engaging directly with national governments on detailed policies – by demonstrating what is possible and indirectly influencing national governments’ international pledges. Traditional trade/industry sector associations and groups have tended to suffer from the ‘lowest common denominator’ effect of their least progressive members. Progressive business groups coalescing around climate ambition can help to counter this. Unlike at the Copenhagen climate talks in 2009, the business community provided a positive, supportive backdrop to the 2015 Paris talks, mindful of the public relations opportunities in taking a progressive stance and of the benefits of targets that reflected the science. The carbon market was a particular focus for corporates, which succeeded in getting emissions trading options and market mechanisms included in Article 6 of the Paris Agreement. Given the challenging political contexts since 2015, the corporate sector will have a key role to play in persuading national governments how technologies and expertise have moved on since the pledges were made. With increasing awareness of resource scarcity, businesses are pursuing ever more creative solutions. Wide recognition that the avoidance of future emissions is increasingly dependent on developing and emerging economies means that business voices from these countries will potentially be more influential in the next few years. 2018-11-28-non-state-actors-climate-corporate-duggan (PDF) Full Article
ac The Role of Sub-state and Non-state Actors in International Climate Processes By www.chathamhouse.org Published On :: Tue, 27 Nov 2018 10:18:41 +0000 The Role of Sub-state and Non-state Actors in International Climate Processes Research paper sysadmin 27 November 2018 In the current international political environment of rising populism, the role of sub- and non-state actors may become more important than ever. — Photo by UNclimatechange, ‘Bonn Climate Change Conference - October 2014’ via Flickr, 2014. Summary Climate action from sub-state and non-state actors such as subnational governments, cities, corporations and NGOs has very significant potential to enhance national efforts to curb CO2 emissions, close the so-called ‘emissions gap’ – between current commitments and the action necessary to meet climate targets – and help move the world on to a ‘1.5°C pathway’ that would limit global warming to 1.5°C above pre-industrial levels by 2100. In addition to their own climate action, sub-state/non-state actors can contribute to climate governance by developing new policies and business models to support emissions cuts and build resilience. Knowledge exchange and capacity-building have a role to play in helping these innovations to spread internationally. Politically, measures implemented by sub-state/non-state actors can help national governments to implement existing targets faster and more effectively, while helping to build political support for more ambitious climate action. The post-Paris climate regime of the United Nations Framework Convention on Climate Change (UNFCCC) reflects the growing importance of sub- and non-state actors, and has featured the creation of institutional structures to engage and coordinate them. In the current international political environment of rising populism, the role of sub- and non-state actors may become more important than ever. However, more questions about the robustness of sub- and non-state action are also likely to be raised. With the 2020 deadline approaching for countries to submit details of enhanced Nationally Determined Contributions (NDCs), long-term climate strategies and other means of raising policy ambition, the next two years are set to provide significant opportunity for sub- and non-state action. Many governments are already developing ways to engage with sub- and non-state actors to identify opportunities to strengthen action by 2020. Key questions in this respect include (a) whether sub- and non-state actors can mobilize across sectors; and (b) whether action can be extended beyond the ‘usual suspects’ to include contributions from less familiar sources, such as business sectors with limited opportunities for climate action or corporations in the Global South. 2018-11-28-non-state-sctors-climate-synthesis-hale-final (PDF) Full Article
ac The Role of Sub-state and Non-state Actors in International Climate Processes: Financial Institutions By www.chathamhouse.org Published On :: Thu, 20 Dec 2018 10:15:53 +0000 The Role of Sub-state and Non-state Actors in International Climate Processes: Financial Institutions Research paper sysadmin 20 December 2018 The trillions of dollars needed to secure the sustainable, climate-compatible pathway outlined in the 2015 Paris Agreement have focused attention on private finance and investment. — Photo by João Barbosa, ‘The need to keep growing’, 2018. This is one of four background papers feeding into a synthesis paper entitled The Role of Sub-state and Non-state Actors in International Climate Processes. Summary The trillions of dollars needed to secure the sustainable, climate-compatible pathway outlined in the 2015 Paris Agreement have focused attention on private finance and investment, and on the role of the financial sector as a potentially powerful non-state actor in the international climate debate. Leading individual financial institutions reacted to the Paris Agreement by framing it in terms of what it would mean for markets – i.e. risks and opportunities – and by underlining the importance of national implementation of climate change commitments. Key recent developments signal that the financial sector actively supports Paris-compatible government action on climate change, as well as company-level action to understand the physical and ‘transition’ risks and opportunities associated with climate change and policy responses. Financial sector engagement is taking place through well-organized and well-supported international initiatives and platforms. A critical part of this process entails robust activity by financial institutions to embed climate change and broader sustainability factors into strategies and operations. At country level, attention to implementation of Nationally Determined Contributions (NDCs) and associated sector-level policy development has been largely separate from the broader ‘sustainable finance’ dynamic. National-level action has not benefited from the same level of organized financial sector involvement evident in international action. One of the reasons for this is that, with some notable exceptions, international financial initiatives lack the capacity and resources to participate in the granular detail of national policy processes. Policymakers in turn often lack the internal capacity to consult or engage with the financial sector domestically. This paper includes some thoughts on further international and national climate actions. Ensuring that messages from successful international financial sector initiatives are heard in regional and non-climate forums offers one avenue for building a stronger foundation for greater climate ambition. Building the resource base for stronger national climate policy engagement, as a counter-voice to incumbent interests and to ensure that the quality of policy is ‘investment grade’, is another. This will be critical to the delivery of policy outcomes. Other key elements include the need to pool knowledge across relevant parts of the finance sector, build alliances, and shift action towards joint problem-solving with policymakers. A ‘Talanoa 2.020’-type initiative offers one potentially promising approach to advancing dialogue in this respect. 2018-12-21-non-state-actors-climate-financial-institutions-hamilton (PDF) Full Article
ac Cooking in Displacement Settings: Engaging the Private Sector in Non-wood-based Fuel Supply By www.chathamhouse.org Published On :: Tue, 22 Jan 2019 13:39:01 +0000 Cooking in Displacement Settings: Engaging the Private Sector in Non-wood-based Fuel Supply Research paper sysadmin 22 January 2019 In displacement settings, providing cooking solutions that reduce negative impacts on the environment and health remains a challenge for local governments, humanitarian agencies, businesses and refugees. — A user of LPG distributed through UNHCR’s SEED programme in the Diffa region of Niger. Photo: Louise Donovan, UNHCR Niger. Summary Providing adequate cooking fuel and clean-burning, fuel-efficient stoves in displacement settings has long been a major challenge for local authorities, humanitarian agencies, non-governmental organizations, local communities and refugees themselves. Refugees generally have limited access to modern cooking solutions. Most either depend on insufficient humanitarian agency handouts of ‘in-kind’ firewood or have to travel long distances to collect firewood. There is significant potential for private-sector engagement in this context – which, though largely overlooked to date, could result in win-win scenarios for all stakeholders. Refugee camps and other displacement settings present opportunities for private-sector cooking fuel companies to expand their customer bases, with the added advantage for vendors of offering concentrated demand and scope for economies of scale. For the Kakuma refugee camp complex in Kenya, the Moving Energy Initiative (MEI) decided to engage with the private sector directly. The MEI requested expressions of interest from local private-sector companies for expanding sales and distribution of fuels in the complex through the concession. The winning company – National Oil Corporation of Kenya – is to receive a prize of $50,000 for its proposed concession to supply liquefied petroleum gas both to refugees in the Kakuma complex and to the surrounding host community. The MEI also conducted interviews with various stakeholders in other contexts and countries who are engaged in efforts to develop market-based approaches to providing clean, fuel-efficient cooking solutions to refugees. Based on the interviews and the concession process, the MEI recommends greater donor investment and longer-term guaranteed funding for cooking interventions. This is needed to allow sufficient time to build sustainable markets and secure the requisite engagement and investments from the private sector. Larger, longer-term investments by the private sector – supported through partnerships with donors and humanitarian agencies – in infrastructure and demand creation (both in and outside the refugee community) can reduce the price of alternative solutions and support a gradual transition away from subsidies. 2019-01-22-PatelGross2 (PDF) Full Article
ac The Role of Sub-state and Non-state Actors in International Climate Processes: Subnational Governments By www.chathamhouse.org Published On :: Wed, 23 Jan 2019 09:34:56 +0000 The Role of Sub-state and Non-state Actors in International Climate Processes: Subnational Governments Research paper sysadmin 23 January 2019 This paper looks at the role of subnational governments in influencing global climate ambition, and makes recommendations for how these actors can increase their influence in the future. — Photo by Annie Spratt, ‘High in the SuperTrees’ via Unsplash, 2017 Summary ‘Subnational governments’ – including municipal, regional and provincial authorities – lack the formal status of negotiating parties to the United Nations Framework Convention on Climate Change (UNFCCC). But they have a vital role to play in informing and helping to shape international climate action, as they are often the key delivery partners for on-the-ground policies. Subnational governments are often closer to climate problems than the UNFCCC parties themselves, and have experience, expertise and peer influence that can support the development of progressive policies and increased ambition. Many subnational governments have joined or formed various groupings to share information and experience, and to increase their collective profile and voice. Notable initiatives and collaborations include the Under2 Coalition, ICLEI, C40 and the Global Covenant of Mayors for Climate & Energy. Subnational governments are highly diverse. In some cases, politically high-profile administrations – the US state of California being a notable example – have exploited their visibility and policy successes to engage in wider climate debates. Equally, however, subnational agendas can encounter resistance from national governments anxious to ensure the primacy of their negotiating positions in the UNFCCC system. One of the advantages that subnational governments enjoy, subject to resources, is their ability to join with peer groups to take a fresh approach to mitigation or adaptation policies. Groups of cities or subnational regions can, through collaborative organizations, explore new approaches that might be less attractive within a national context. To maintain and build on their current achievements and influence, subnational governments need, among other things, to: improve the credibility of their experience through evaluation of the success of their climate policies; use membership of appropriate international groups to share experience and boost their leverage; continue to create collaborative relationships with progressive businesses to increase influence at a national level; build on cross-regional relationships in climate adaptation and resilience; and work with other subnational actors to build momentum ahead of the first post-Paris revision of climate commitments in 2020. 2019-01-23-Duggan (PDF) Full Article
ac Adopting a Market-based Approach to Boost Energy Access in Displaced Contexts By www.chathamhouse.org Published On :: Mon, 25 Mar 2019 10:18:12 +0000 Adopting a Market-based Approach to Boost Energy Access in Displaced Contexts Research paper sysadmin 25 March 2019 This paper evaluates the market-based approaches adopted in the MEI projects in Kenya and Burkina Faso. It articulates how such commercial strategies can be applied to the delivery of energy in displacement settings and compares this to real world examples. — A shop selling fabric and electronics inside the Dagahaley Camp, one of five camps that make up Dadaab, the world’s largest and oldest camp for refugees. Photo: Michelle Shephard/Toronto Star via Getty Images. Development of long-term energy solutions in displacement settings tends to be perceived as investment that falls outside the remit of emergency responses. In addition, when emergency energy supply measures are implemented they often result in expensive, unreliable and unhealthy energy provision for those in protracted or recurrent crises. There is widespread agreement among humanitarian and development experts that an effective refugee response should include long-term development solutions as well as emergency relief. The energy access imperative is more pronounced when considering the need for effective energy distribution in practically all camp activities and basic necessities: pumping and treatment of clean water; heating and cooling for food storage and cooking; energy for livelihood activities; and provision of light for schooling, hospitals and the prevention of violence against women and children. Minor shifts in household energy use to basic solar lighting options and non-wood fuels would save $303 million annually on refugee fuel costs. Within refugee contexts in Kenya and Burkina Faso, the MEI sought to examine opportunities to use market interventions, rather than in-kind distributions, to improve clean energy access over the long-term and test the delivery of market-based approaches. 2019-03-25-MEIWhitehouse (PDF) Full Article
ac Infrastructure Management Contracts: Improving Energy Asset Management in Displacement Settings By www.chathamhouse.org Published On :: Wed, 17 Apr 2019 15:09:12 +0000 Infrastructure Management Contracts: Improving Energy Asset Management in Displacement Settings Research paper sysadmin 17 April 2019 This paper highlights a number of options for managing electricity infrastructure in refugee camps and outlines the challenges, opportunities and operational implications associated with them. It takes the Kalobeyei settlement in Kenya as a case study. — A solar array installed for International Rescue Committee health clinics in Kakuma refugee camp, Kenya. Photo: Kube Energy Building and maintaining electricity infrastructure to power offices, businesses, households and other operations in displacement settings is difficult. It is especially challenging for the Office of the United Nations High Commissioner for Refugees (UNHCR) and its partner agencies, because supplying electricity is not their core business. Private-sector companies exist that are willing and able to develop infrastructure management contracts to provide energy as a service in displacement settings. However, institutional barriers within humanitarian agencies persist, with short budgeting cycles in particular preventing humanitarian agencies from entering into the sorts of long-term service agreements required by the private sector. A number of options exist to leverage the expertise of the private sector through ‘public–private partnership’ (P3) structures. Such mechanisms can promote more efficient management of infrastructure by drawing on private-sector experience and expertise, incentivizing appropriate risk-sharing and providing options to leverage private capital in project development. Field work from the Kalobeyei settlement in Kenya suggests that a solar/diesel hybrid mini-grid solution was the most economical option to power camp services and infrastructure there. Compared to distributed diesel generation, the annual savings in operating costs were estimated at $49,880, with the additional investment paid back within 3.6 years. Humanitarian agencies need to be willing to change their policies to enable long-term service agreements. Alternatively (or, more likely, in conjunction with this option), financial mechanisms such as partial risk guarantees need to be developed to offset some of the risks. This change will need high-level support from donors and humanitarian agencies. Once the first infrastructure management contracts can be signed and tested in displacement locations (through the use of donor funding or otherwise) and associated data collected, it will ease the way for future investments in these types of projects. 2019-04-17-MEI-Infrastructure Management Contracts (PDF) Full Article
ac Secrets and Spies: UK Intelligence Accountability After Iraq and Snowden By www.chathamhouse.org Published On :: Wed, 15 Jan 2020 09:23:12 +0000 Secrets and Spies: UK Intelligence Accountability After Iraq and Snowden Book sysadmin 15 January 2020 How can democratic governments hold intelligence and security agencies to account when what they do is largely secret? Jamie Gaskarth explores how intelligence professionals view accountability in the context of 21st century politics. Using the UK as a case study, this book provides the first systematic exploration of how accountability is understood inside the secret world. It is based on new interviews with current and former UK intelligence practitioners, as well as extensive research into the performance and scrutiny of the UK intelligence machinery. The result is the first detailed analysis of how intelligence professionals view their role, what they feel keeps them honest, and how far external overseers impact on their work. The UK gathers material that helps inform global decisions on such issues as nuclear proliferation, terrorism, transnational crime, and breaches of international humanitarian law. On the flip side, the UK was a major contributor to the intelligence failures leading to the Iraq war in 2003, and its agencies were complicit in the widely discredited U.S. practices of torture and ‘rendition’ of terrorism suspects. UK agencies have come under greater scrutiny since those actions, but it is clear that problems remain. Secrets and Spies is the result of a British Academy funded project (SG151249) on intelligence accountability. The book is published as part of the Insights series. Praise for Secrets and Spies Open society is increasingly defended by secret means. For this reason, oversight has never been more important. This book offers a new exploration of the widening world of accountability for UK intelligence, encompassing informal as well as informal mechanisms. It substantiates its claims well, drawing on an impressive range of interviews with senior figures. This excellent book offers both new information and fresh interpretations. It will have a major impact. Richard Aldrich, Professor of International Security, University of Warwick, UK About the author Jamie Gaskarth is Professor of Foreign Policy and International Relations at The Open University. He was previously senior lecturer at the University of Birmingham where he taught strategy and decision-making. His research focused on the ethical dilemmas of leadership and accountability in intelligence, foreign policy, and defence. He is author/editor or co-editor of six books and served on the Academic Advisory panel for the 2015 UK National Security Strategy and Strategic Defence and Security Review. Purchase UK (via Amazon) Rest of world (via Brookings Institution Press) Students (via Browns Books) Full Article
ac Impact report 2020–21 By www.chathamhouse.org Published On :: Wed, 14 Jul 2021 15:44:51 +0000 Impact report 2020–21 Other resource dora.popova 14 July 2021 Explore our policy impact in the past year, including through our research, convening and next generation initiatives, in a revised format annual review. Chair’s statement It has been an extraordinary year of change for us all. The COVID-19 pandemic is the greatest challenge to the world for generations. Millions have lost their lives or suffered devastating impacts on their health, both from COVID-19 itself and because health systems have been unable to deliver treatments for other conditions. The pandemic has also caused the greatest shock to the global economy since the 1930s, setting back the progress of recent years in eliminating poverty, getting more children into education and improving global health. This means Chatham House is needed more than ever. Our world-leading convening and cutting-edge research on the major challenges facing the world, from building more sustainable economic growth and tackling climate change to easing geopolitical tensions, has continued despite the challenges of lockdown. For that I pay tribute to the resilience and ingenuity of the staff who have found innovative solutions to the obstacles presented by the pandemic, all while working largely from home. This year I am also delighted to note the exceptional gift of £10 million from the MAVA Foundation to enable us to launch the Sustainability Accelerator. This initiative builds on the Hoffmann Centre’s last five years of innovative convening and activity. And it puts sustainability at the core of the institute’s work in this critical year for addressing climate change and biodiversity. So, as I prepare to step down from my three years as chair of the institute, I would like to thank my fellow Council members and Robin Niblett and his team for their hard work and ambition to deliver on Chatham House’s mission. I have also been especially pleased to see how we are engaging younger, more diverse audiences through the next generation initiatives, including our Panel of Young Advisers, the Common Futures Conversations project, the QEII Academy Ambassadors, our Internship Programme and the Chatham House-SNF CoLab. I am particularly pleased about the Chatham House Summer School, where 16–18-year-olds can now engage with experts on international affairs and get an insight into careers within the charity and not-for-profit sector. It has been an honour to lead this extraordinary institution and I look forward to continuing my involvement with Chatham House in new ways. Lord Jim O’Neill Impact Report 2020-21 (PDF) Full Article
ac Mycobacteria excise DNA damage in 12- or 13-nucleotide-long oligomers by prokaryotic-type dual incisions and performs transcription-coupled repair [Genomics and Proteomics] By www.jbc.org Published On :: 2020-12-11T00:06:21-08:00 In nucleotide excision repair, bulky DNA lesions such as UV-induced cyclobutane pyrimidine dimers are removed from the genome by concerted dual incisions bracketing the lesion, followed by gap filling and ligation. So far, two dual-incision patterns have been discovered: the prokaryotic type, which removes the damage in 11–13-nucleotide-long oligomers, and the eukaryotic type, which removes the damage in 24–32-nucleotide-long oligomers. However, a recent study reported that the UvrC protein of Mycobacterium tuberculosis removes damage in a manner analogous to yeast and humans in a 25-mer oligonucleotide arising from incisions at 15 nt from the 3´ end and 9 nt from the 5´ end flanking the damage. To test this model, we used the in vivo excision assay and the excision repair sequencing genome-wide repair mapping method developed in our laboratory to determine the repair pattern and genome-wide repair map of Mycobacterium smegmatis. We find that M. smegmatis, which possesses homologs of the Escherichia coli uvrA, uvrB, and uvrC genes, removes cyclobutane pyrimidine dimers from the genome in a manner identical to the prokaryotic pattern by incising 7 nt 5´ and 3 or 4 nt 3´ to the photoproduct, and performs transcription-coupled repair in a manner similar to E. coli. Full Article
ac Nonspecific DNA binding by P1 ParA determines the distribution of plasmid partition and repressor activities [Microbiology] By www.jbc.org Published On :: 2020-12-11T00:06:21-08:00 The faithful segregation, or “partition,” of many low-copy number bacterial plasmids is driven by plasmid-encoded ATPases that are represented by the P1 plasmid ParA protein. ParA binds to the bacterial nucleoid via an ATP-dependent nonspecific DNA (nsDNA)-binding activity, which is essential for partition. ParA also has a site-specific DNA-binding activity to the par operator (parOP), which requires either ATP or ADP, and which is essential for it to act as a transcriptional repressor but is dispensable for partition. Here we examine how DNA binding by ParA contributes to the relative distribution of its plasmid partition and repressor activities, using a ParA with an alanine substitution at Arg351, a residue previously predicted to participate in site-specific DNA binding. In vivo, the parAR351A allele is compromised for partition, but its repressor activity is dramatically improved so that it behaves as a “super-repressor.” In vitro, ParAR351A binds and hydrolyzes ATP, and undergoes a specific conformational change required for nsDNA binding, but its nsDNA-binding activity is significantly damaged. This defect in turn significantly reduces the assembly and stability of partition complexes formed by the interaction of ParA with ParB, the centromere-binding protein, and DNA. In contrast, the R351A change shows only a mild defect in site-specific DNA binding. We conclude that the partition defect is due to altered nsDNA binding kinetics and affinity for the bacterial chromosome. Furthermore, the super-repressor phenotype is explained by an increased pool of non-nucleoid bound ParA that is competent to bind parOP and repress transcription. Full Article
ac Optimized incorporation of an unnatural fluorescent amino acid affords measurement of conformational dynamics governing high-fidelity DNA replication [DNA and Chromosomes] By www.jbc.org Published On :: 2020-12-11T00:06:21-08:00 DNA polymerase from bacteriophage T7 undergoes large, substrate-induced conformational changes that are thought to account for high replication fidelity, but prior studies were adversely affected by mutations required to construct a Cys-lite variant needed for site-specific fluorescence labeling. Here we have optimized the direct incorporation of a fluorescent un-natural amino acid, (7-hydroxy-4-coumarin-yl)-ethylglycine, using orthogonal amber suppression machinery in Escherichia coli. MS methods verify that the unnatural amino acid is only incorporated at one position with minimal background. We show that the single fluorophore provides a signal to detect nucleotide-induced conformational changes through equilibrium and stopped-flow kinetic measurements of correct nucleotide binding and incorporation. Pre-steady-state chemical quench methods show that the kinetics and fidelity of DNA replication catalyzed by the labeled enzyme are largely unaffected by the unnatural amino acid. These advances enable rigorous analysis to establish the kinetic and mechanistic basis for high-fidelity DNA replication. Full Article
ac Kinetic investigation of the polymerase and exonuclease activities of human DNA polymerase ϵ holoenzyme [DNA and Chromosomes] By www.jbc.org Published On :: 2020-12-11T00:06:21-08:00 In eukaryotic DNA replication, DNA polymerase ε (Polε) is responsible for leading strand synthesis, whereas DNA polymerases α and δ synthesize the lagging strand. The human Polε (hPolε) holoenzyme is comprised of the catalytic p261 subunit and the noncatalytic p59, p17, and p12 small subunits. So far, the contribution of the noncatalytic subunits to hPolε function is not well understood. Using pre-steady-state kinetic methods, we established a minimal kinetic mechanism for DNA polymerization and editing catalyzed by the hPolε holoenzyme. Compared with the 140-kDa N-terminal catalytic fragment of p261 (p261N), which we kinetically characterized in our earlier studies, the presence of the p261 C-terminal domain (p261C) and the three small subunits increased the DNA binding affinity and the base substitution fidelity. Although the small subunits enhanced correct nucleotide incorporation efficiency, there was a wide range of rate constants when incorporating a correct nucleotide over a single-base mismatch. Surprisingly, the 3'→5' exonuclease activity of the hPolε holoenzyme was significantly slower than that of p261N when editing both matched and mismatched DNA substrates. This suggests that the presence of p261C and the three small subunits regulates the 3'→5' exonuclease activity of the hPolε holoenzyme. Together, the 3'→5' exonuclease activity and the variable mismatch extension activity modulate the overall fidelity of the hPolε holoenzyme by up to 3 orders of magnitude. Thus, the presence of p261C and the three noncatalytic subunits optimizes the dual enzymatic activities of the catalytic p261 subunit and makes the hPolε holoenzyme an efficient and faithful replicative DNA polymerase. Full Article
ac Phosphorylation of SMURF2 by ATM exerts a negative feedback control of DNA damage response [DNA and Chromosomes] By www.jbc.org Published On :: 2020-12-25T00:06:31-08:00 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. Full Article
ac 30 low-key acquisitions who could pay off big By mlb.mlb.com Published On :: Tue, 12 Feb 2019 13:57:13 EDT Fans and analysts spend the entire offseason speculating where the top free agents could go, but sometimes an under-the-radar pickup can end up making a world of difference. As positional competitions begin to heat up at Spring Training camps this month, MLB.com's beat writers were asked to identify one potentially overlooked acquisition for each of the 30 clubs. Here's who they came up with. Full Article
ac Kapler faces pressure, shifts focus to players By mlb.mlb.com Published On :: Wed, 13 Feb 2019 17:33:15 EDT Gabe Kapler is trying to keep the focus on his players in 2019, but it might be an impossible task. Full Article
ac MacPhail: Phils are 'uniquely poised right now' By mlb.mlb.com Published On :: Fri, 15 Feb 2019 17:56:39 EDT Phillies president Andy MacPhail opened a 28-minute press conference on Friday afternoon at Spectrum Field with facts and figures about investments the organization made the past few seasons as the team wallowed at the bottom of the National League. Then MacPhail talked a lot about Bryce Harper and Manny Machado as well as manager Gabe Kapler. Full Article
ac Reasons for optimism for each MLB club By mlb.mlb.com Published On :: Sun, 17 Feb 2019 21:02:04 EDT On this opening week of Spring Training, all 30 Major League teams have one thing in common: optimism. Here's an optimism cheat sheet for each of them. Full Article
ac Eickhoff throws first bullpen since setback By mlb.mlb.com Published On :: Sun, 17 Feb 2019 15:23:25 EDT Jerad Eickhoff took his latest first step on Sunday morning at Spectrum Field. He threw a bullpen session, his first since sustaining a setback last month following carpal tunnel surgery in October. Full Article
ac Kapler preaches focus at camp amid rumors By mlb.mlb.com Published On :: Mon, 18 Feb 2019 16:04:55 EDT Phillies manager Gabe Kapler has a little advice for the players who could be impacted most if the team signs Bryce Harper or Manny Machado. Full Article
ac 30 low-key acquisitions who could pay off big By mlb.mlb.com Published On :: Tue, 12 Feb 2019 13:57:13 EDT Fans and analysts spend the entire offseason speculating where the top free agents could go, but sometimes an under-the-radar pickup can end up making a world of difference. As positional competitions begin to heat up at Spring Training camps this month, MLB.com's beat writers were asked to identify one potentially overlooked acquisition for each of the 30 clubs. Here's who they came up with. Full Article
ac Healthy Cozart eyes bounce-back season By mlb.mlb.com Published On :: Fri, 15 Feb 2019 15:36:33 EDT After undergoing surgery in late June to repair a torn left labrum in his left shoulder that required nine anchors to be inserted to keep everything in place, Zack Cozart is healthy and looking for a bounce-back season with the Angels. Full Article
ac Halos announce Minor League coaching staffs By mlb.mlb.com Published On :: Sat, 16 Feb 2019 15:14:58 EDT The Angels announced their Minor League coaching staffs on Saturday, including former Major League catcher Lou Marson being named the new manager of Triple-A Salt Lake and former big leaguer David Newhan as the new skipper at Double-A Birmingham. Full Article
ac Reasons for optimism for each MLB club By mlb.mlb.com Published On :: Sun, 17 Feb 2019 21:02:04 EDT On this opening week of Spring Training, all 30 Major League teams have one thing in common: optimism. Here's an optimism cheat sheet for each of them. Full Article
ac Trout on contract talks: 'I don't want to comment' By mlb.mlb.com Published On :: Mon, 18 Feb 2019 14:54:02 EDT Mike Trout and owner Arte Moreno met separately with the media on Monday, but neither would confirm that extension talks have begun between the Angels and Trout's agent, Craig Landis. Full Article
ac Covid-19: NHS staff will be offered vaccine this autumn, but JCVI recommends more limited rollout By www.bmj.com Published On :: Monday, August 5, 2024 - 09:51 Full Article
ac Whooping cough: Health officials urge pregnant women to get vaccinated as another infant dies By www.bmj.com Published On :: Friday, August 9, 2024 - 12:56 Full Article
ac First mpox vaccines arrive in Africa as officials work “blindly” to contain outbreaks By www.bmj.com Published On :: Thursday, August 29, 2024 - 11:12 Full Article