Purinergic signaling by extracellular ATP regulates a variety of cellular events and is implicated in both normal physiology and pathophysiology. Several molecules have been associated with the release of ATP and other small molecules, but their precise contributions have been difficult to assess because of their complexity and heterogeneity. Here, we report on the results of a gain-of-function screen for modulators of hypotonicity-induced ATP release using HEK-293 cells and murine cerebellar granule neurons, along with bioluminescence, calcium FLIPR, and short hairpin RNA–based gene-silencing assays. This screen utilized the most extensive genome-wide ORF collection to date, covering 90% of human, nonredundant, protein-encoding genes. We identified two ABCG1 (ABC subfamily G member 1) variants, which regulate cellular cholesterol, as modulators of hypotonicity-induced ATP release. We found that cholesterol levels control volume-regulated anion channel–dependent ATP release. These findings reveal novel mechanisms for the regulation of ATP release and volume-regulated anion channel activity and provide critical links among cellular status, cholesterol, and purinergic signaling.

pncRNA-D is an irradiation-induced 602-nt long noncoding RNA transcribed from the promoter region of the cyclin D1 (CCND1) gene. CCND1 expression is predicted to be inhibited through an interplay between pncRNA-D and RNA-binding protein TLS/FUS. Because the pncRNA-D–TLS interaction is essential for pncRNA-D–stimulated CCND1 inhibition, here we studied the possible role of RNA modification in this interaction in HeLa cells. We found that osmotic stress induces pncRNA-D by recruiting RNA polymerase II to its promoter. pncRNA-D was highly m6A-methylated in control cells, but osmotic stress reduced the methylation and also arginine methylation of TLS in the nucleus. Knockdown of the m6A modification enzyme methyltransferase-like 3 (METTL3) prolonged the half-life of pncRNA-D, and among the known m6A recognition proteins, YTH domain-containing 1 (YTHDC1) was responsible for binding m6A of pncRNA-D. Knockdown of METTL3 or YTHDC1 also enhanced the interaction of pncRNA-D with TLS, and results from RNA pulldown assays implicated YTHDC1 in the inhibitory effect on the TLS–pncRNA-D interaction. CRISPR/Cas9-mediated deletion of candidate m6A site decreased the m6A level in pncRNA-D and altered its interaction with the RNA-binding proteins. Of note, a reduction in the m6A modification arrested the cell cycle at the G0/G1 phase, and pncRNA-D knockdown partially reversed this arrest. Moreover, pncRNA-D induction in HeLa cells significantly suppressed cell growth. Collectively, these findings suggest that m6A modification of the long noncoding RNA pncRNA-D plays a role in the regulation of CCND1 gene expression and cell cycle progression.

Prominins (proms) are transmembrane glycoproteins conserved throughout the animal kingdom. They are associated with plasma membrane protrusions, such as primary cilia, as well as extracellular vesicles derived thereof. Primary cilia host numerous signaling pathways affected in diseases known as ciliopathies. Human PROM1 (CD133) is detected in both somatic and cancer stem cells and is also expressed in terminally differentiated epithelial and photoreceptor cells. Genetic mutations in the PROM1 gene result in retinal degeneration by impairing the proper formation of the outer segment of photoreceptors, a modified cilium. Here, we investigated the impact of proms on two distinct examples of ciliogenesis. First, we demonstrate that the overexpression of a dominant-negative mutant variant of human PROM1 (i.e. mutation Y819F/Y828F) significantly decreases ciliary length in Madin–Darby canine kidney cells. These results contrast strongly to the previously observed enhancing effect of WT PROM1 on ciliary length. Mechanistically, the mutation impeded the interaction of PROM1 with ADP-ribosylation factor–like protein 13B, a key regulator of ciliary length. Second, we observed that in vivo knockdown of prom3 in zebrafish alters the number and length of monocilia in the Kupffer's vesicle, resulting in molecular and anatomical defects in the left-right asymmetry. These distinct loss-of-function approaches in two biological systems reveal that prom proteins are critical for the integrity and function of cilia. Our data provide new insights into ciliogenesis and might be of particular interest for investigations of the etiologies of ciliopathies.

The traditionally blue-collar neighbourhood of Sham Shui Po is home to a kaleidoscopic collection of landmarks, streets and shops.

Participants of the Sham Shui Po Ensemble project explored the area and told its story through video and music production.

One of the project’s creative productions, the short film Collage created by Cobe Yau and her team, documented the daily lives of the area’s residents.

Ms Yau said Sham Shui Po’s diversity inspired her team to combine footage of residents’ daily activities, such as the unloading of meat and vegetables in wet markets and hawkers selling their wares.

“We hope our viewers can realise that although there are some street sleepers and it may be a bit grimy in some parts of Sham Shui Po, there are also many interesting aspects that make this community stand out.”

Creative journeys

Sham Shui Po Ensemble is under the Community Record Company, an 18-month community-based programme which also showcases two other unique locales.

Last year, participants explored Sai Ying Pun under the West Side Re-Discovery project. Sham Shui Po Ensemble was launched in April and concluded in late July, while the Wander in To Kwa Wan project began this month.

Local documentary maker Wong Siu-pong, the Community Curator of the Sham Shui Po project, hopes participants are able to explore the community without bias.

“Apart from the basics of film production, I did not teach them a lot of filmmaking skills. I hope they learn to be humble when making a documentary.

“A lot of the time, we read the news to learn about a community. I hope they can discover these places without prejudice, this is important.”

Project participants were also able to paint a picture of the community with music.

Warren Luk joined the project’s music stream and wrote the song Rich on Life with his team.

“People always have preconceived ideas of Sham Shui Po. But when you walk through the neighbourhood, you can find lots of quirky and interesting landmarks.

“When you observe the interactions between residents there, you can see that although their lives may be tough, they are enjoying themselves a lot. It is very inspiring.”

The Community Record Company programme is organised by non-governmental organisation MaD Institute and sponsored by the Home Affairs Bureau’s Arts Capacity Development Funding Scheme, which seeks to strengthen Hong Kong’s cultural software and build up the arts sector.

Application details for the next funding exercise will be available in November.

(University of Chicago Press Journals) Extensive cooperation among biologically unrelated individuals is uniquely human. It would be surprising if this uniqueness were not related to other uniquely human characteristics, yet current theories of human cooperation tend to ignore the human aspects of human behavior. This paper presents a theory of cooperation that draws on social, cultural, and psychological aspects of human uniqueness for which current theories have little or no explanation.

Apr 1, 2004; 17:97-101
Articles

Management professors Adam Galinksy and Paul Ingram, together with Jonathan Laor ’21, CEO of Applicaster, advise on leadership during a crisis.

Georg H H Borner
Apr 28, 2020; 0:R120.001971v1-mcp.R120.001971
Review

Guest blog by Stephen McKean On my first day of college, I showed up an hour early to my very first class. The class was Math 2210, multivariable calculus. For some reason, I thought this was the highest math class … Continue reading →

6 November 2019 , Volume 95, Number 6

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.

Protein subcellular localization is an essential and highly regulated determinant of protein function. Major advances in mass spectrometry and imaging have allowed the development of powerful spatial proteomics approaches for determining protein localization at the whole cell scale. Here, a brief overview of current methods is presented, followed by a detailed discussion of organellar mapping through proteomic profiling. This relatively simple yet flexible approach is rapidly gaining popularity, due to its ability to capture the localizations of thousands of proteins in a single experiment. It can be used to generate high-resolution cell maps, and as a tool for monitoring protein localization dynamics. This review highlights the strengths and limitations of the approach, and provides guidance to designing and interpreting profiling experiments. 

Obesity is a risk factor for type 2 diabetes (T2D), however not all obese individuals develop the disease. In this study, we aimed to investigate the cause of differential insulin secretion capacity of pancreatic islets from T2D and non-T2D (ND) especially obese donors (BMI ≥30 kg/m²). Islets from obese T2D donors had reduced insulin secretion, decreased β-cell exocytosis and higher expression of fatty acid translocase CD36. We tested the hypothesis that CD36 is a key molecule in the reduced insulin secretion capacity. Indeed, CD36 overexpression led to decreased insulin secretion, impaired exocytosis and reduced granule docking. This was accompanied with reduced expression of the exocytotic proteins, SNAP25, STXBP1 and VAMP2, likely because CD36 induced down-regulation of the IRS proteins, suppressed insulin signaling PI3K-AKT pathway and increased nuclear localization of the transcription factor FoxO1. CD36 antibody treatment of the human β-cell line, EndoC-βH1, increased IRS1 and exocytotic protein levels, improved granule docking and enhanced insulin secretion. Our results demonstrate that β-cells from obese T2D donors have dysfunctional exocytosis likely due to an abnormal lipid handling represented by differential CD36 expression. Hence, CD36 could be a key molecule to limit β-cell function in T2D associated with obesity.

Prominins (proms) are transmembrane glycoproteins conserved throughout the animal kingdom. They are associated with plasma membrane protrusions, such as primary cilia, as well as extracellular vesicles derived thereof. Primary cilia host numerous signaling pathways affected in diseases known as ciliopathies. Human PROM1 (CD133) is detected in both somatic and cancer stem cells and is also expressed in terminally differentiated epithelial and photoreceptor cells. Genetic mutations in the PROM1 gene result in retinal degeneration by impairing the proper formation of the outer segment of photoreceptors, a modified cilium. Here, we investigated the impact of proms on two distinct examples of ciliogenesis. First, we demonstrate that the overexpression of a dominant-negative mutant variant of human PROM1 (i.e. mutation Y819F/Y828F) significantly decreases ciliary length in Madin–Darby canine kidney cells. These results contrast strongly to the previously observed enhancing effect of WT PROM1 on ciliary length. Mechanistically, the mutation impeded the interaction of PROM1 with ADP-ribosylation factor–like protein 13B, a key regulator of ciliary length. Second, we observed that in vivo knockdown of prom3 in zebrafish alters the number and length of monocilia in the Kupffer's vesicle, resulting in molecular and anatomical defects in the left-right asymmetry. These distinct loss-of-function approaches in two biological systems reveal that prom proteins are critical for the integrity and function of cilia. Our data provide new insights into ciliogenesis and might be of particular interest for investigations of the etiologies of ciliopathies.

Tumor cells can spread to distant sites through their ability to switch between mesenchymal and amoeboid (bleb-based) migration. Because of this difference, inhibitors of metastasis must account for each migration mode. However, the role of vimentin in amoeboid migration has not been determined. Because amoeboid leader bleb–based migration (LBBM) occurs in confined spaces and vimentin is known to strongly influence cell-mechanical properties, we hypothesized that a flexible vimentin network is required for fast amoeboid migration. To this end, here we determined the precise role of the vimentin intermediate filament system in regulating the migration of amoeboid human cancer cells. Vimentin is a classic marker of epithelial-to-mesenchymal transition and is therefore an ideal target for a metastasis inhibitor. Using a previously developed polydimethylsiloxane slab–based approach to confine cells, RNAi-based vimentin silencing, vimentin overexpression, pharmacological treatments, and measurements of cell stiffness, we found that RNAi-mediated depletion of vimentin increases LBBM by ∼50% compared with control cells and that vimentin overexpression and simvastatin-induced vimentin bundling inhibit fast amoeboid migration and proliferation. Importantly, these effects were independent of changes in actomyosin contractility. Our results indicate that a flexible vimentin intermediate filament network promotes LBBM of amoeboid cancer cells in confined environments and that vimentin bundling perturbs cell-mechanical properties and inhibits the invasive properties of cancer cells.

11 July 2014

Rising HFC use poses a significant threat to intergovernmental efforts to combat climate change. At present, there is a glaring regulatory gap in this area. Although challenging, there is no reason why the international community cannot come together to address this new problem of coordination and ensure that legal regimes support each other.

Aging-dependent changes in tissue function are associated with the development of metabolic diseases. However, the molecular connections linking aging, obesity, and diabetes remain unclear. Lamin A, lamin C, and progerin, products of the Lmna gene, have antagonistic functions on energy metabolism and life span. Lamin C, albeit promoting obesity, increases life span, suggesting that this isoform is crucial for maintaining healthy conditions under metabolic stresses. Because β-cell loss during obesity or aging leads to diabetes, we investigated the contribution of lamin C to β-cell function in physiopathological conditions. We demonstrate that aged lamin C only–expressing mice (Lmna^LCS/LCS) become obese but remain glucose tolerant due to adaptive mechanisms including increased β-cell mass and insulin secretion. Triggering diabetes in young mice revealed that Lmna^LCS/LCS animals normalize their fasting glycemia by both increasing insulin secretion and regenerating β-cells. Genome-wide analyses combined to functional analyses revealed an increase of mitochondrial biogenesis and global translational rate in Lmna^LCS/LCS islets, two major processes involved in insulin secretion. Altogether, our results demonstrate for the first time that the sole expression of lamin C protects from glucose intolerance through a β-cell–adaptive transcriptional program during metabolic stresses, highlighting Lmna gene processing as a new therapeutic target for diabetes treatment.

T Inoguchi
Nov 1, 2000; 49:1939-1945
Articles

Glucagon-like peptide 1 (GLP-1) mimetics are effective drugs for treatment of type 2 diabetes, and there is consequently extensive interest in increasing endogenous GLP-1 secretion and L-cell abundance. Here we identify G-protein–coupled bile acid receptor 1 (GPBAR1) as a selective regulator of intestinal L-cell differentiation. Lithocholic acid and the synthetic GPBAR1 agonist, L3740, selectively increased L-cell density in mouse and human intestinal organoids and elevated GLP-1 secretory capacity. L3740 induced expression of Gcg and transcription factors Ngn3 and NeuroD1. L3740 also increased the L-cell number and GLP-1 levels and improved glucose tolerance in vivo. Further mechanistic examination revealed that the effect of L3740 on L cells required intact GLP-1 receptor and serotonin 5-hydroxytryptamine receptor 4 (5-HT4) signaling. Importantly, serotonin signaling through 5-HT4 mimicked the effects of L3740, acting downstream of GLP-1. Thus, GPBAR1 agonists and other powerful GLP-1 secretagogues facilitate L-cell differentiation through a paracrine GLP-1–dependent and serotonin-mediated mechanism.

The COVID-19 pandemic around the world has taken the world by storm, touching the lives of every human being on Earth. The global nature of the crisis has united us as human beings and tragedy and deaths in any country by COVID-19 worry us all....

Insulin-mediated microvascular recruitment (IMVR) regulates delivery of insulin and glucose to insulin-sensitive tissues. We have previously proposed that perivascular adipose tissue (PVAT) controls vascular function through outside-to-inside communication and through vessel-to-vessel, or "vasocrine," signaling. However, direct experimental evidence supporting a role of local PVAT in regulating IMVR and insulin sensitivity in vivo is lacking. Here, we studied muscles with and without PVAT in mice using combined contrast-enhanced ultrasonography and intravital microscopy to measure IMVR and gracilis artery diameter at baseline and during the hyperinsulinemic-euglycemic clamp. We show, using microsurgical removal of PVAT from the muscle microcirculation, that local PVAT depots regulate insulin-stimulated muscle perfusion and glucose uptake in vivo. We discovered direct microvascular connections between PVAT and the distal muscle microcirculation, or adipomuscular arterioles, the removal of which abolished IMVR. Local removal of intramuscular PVAT altered protein clusters in the connected muscle, including upregulation of a cluster featuring Hsp90ab1 and Hsp70 and downregulation of a cluster of mitochondrial protein components of complexes III, IV, and V. These data highlight the importance of PVAT in vascular and metabolic physiology and are likely relevant for obesity and diabetes.

Reduced storage of dietary fatty acids (DFAs) in abdominal adipose tissues with enhanced cardiac partitioning has been shown in subjects with type 2 diabetes (T2D) and prediabetes. We measured DFA metabolism and organ partitioning using positron emission tomography with oral and intravenous long-chain fatty acid and glucose tracers during a standard liquid meal in 12 obese subjects with T2D before and 8–12 days after bariatric surgery (sleeve gastrectomy or sleeve gastrectomy and biliopancreatic diversion with duodenal switch). Bariatric surgery reduced cardiac DFA uptake from a median (standard uptake value [SUV]) 1.75 (interquartile range 1.39–2.57) before to 1.09 (1.04–1.53) after surgery (P = 0.01) and systemic DFA spillover from 56.7 mmol before to 24.7 mmol over 6 h after meal intake after surgery (P = 0.01), with a significant increase in intra-abdominal adipose tissue DFA uptake from 0.15 (0.04–0.31] before to 0.49 (0.20–0.59) SUV after surgery (P = 0.008). Hepatic insulin resistance was significantly reduced in close association with increased DFA storage in intra-abdominal adipose tissues (r = –0.79, P = 0.05) and reduced DFA spillover (r = 0.76, P = 0.01). We conclude that bariatric surgery in subjects with T2D rapidly reduces cardiac DFA partitioning and hepatic insulin resistance at least in part through increased intra-abdominal DFA storage and reduced spillover.

Current therapeutic strategies for diabetic foot ulcer (DFU) have focused on developing topical healing agents, but few agents have controlled prospective data to support their effectiveness in promoting wound healing. We tested a stem cell mobilizing therapy for DFU using a combination of AMD3100 and low-dose FK506 (tacrolimus) (AF) in streptozocin-induced type 1 diabetic (T1DM) rats and type 2 diabetic Goto-Kakizaki (GK) rats that had developed peripheral artery disease and neuropathy. Here, we show that the time for healing back wounds in T1DM rats was reduced from 27 to 19 days, and the foot wound healing time was reduced from 25 to 20 days by treatment with AF (subcutaneously, every other day). Similarly, in GK rats treated with AF, the healing time on back wounds was reduced from 26 to 21 days. Further, this shortened healing time was accompanied by reduced scar and by regeneration of hair follicles. We found that AF therapy mobilized and recruited bone marrow–derived CD133⁺ and CD34⁺ endothelial progenitor cells and Ym1/2⁺ M2 macrophages into the wound sites, associated with enhanced capillary and hair follicle neogenesis. Moreover, AF therapy improved microcirculation in diabetic and neuropathic feet in GK rats. This study provides a novel systemic therapy for healing DFU.

Jackie Robinson was born a century ago this Jan. 31. To commemorate the 100th anniversary of the birth of one of baseball's most important pioneers, Major League Baseball has planned a yearlong slate of activities in Robinson's honor.

Where can you find the most accurate statistics on some of the top immigration issues—ranging from the size of immigrant and emigrant populations, to humanitarian and labor flows, naturalization rates, enforcement statistics, remittances, and more? In this brief video, Jeanne Batalova, who manages the Migration Policy Institute’s Migration Data Hub, walks you through the Immigration Data Matters guide developed by MPI and the Population Reference Bureau.
 

The Armenian diaspora, which significantly exceeds the country's resident population, has played an instrumental role in Armenia's political and economic development since independence in 1991. Yet a picture emerges of divergent currents within the diaspora, often seen from above as a unified entity. Delve into differences in engagement among Armenia's "old" and "new" diasporas with this feature article.

The Modi government's push for a Citizenship Amendment Act and National Register of Citizens sparked deadly riots and chilled India's 200 million Muslims, who fear being relegated to second-class citizenship—and for some, even statelessness. This article explores actions by Modi's Bharatiya Janata Party, the significance of Bangladeshi illegal immigration as a driver, and what a register of citizens in Assam might mean for India.

War and impending famine in Yemen have captured significant attention. Yet often overlooked is the country’s role as the epicenter of one of the world’s busiest mixed migration routes, linking Africa, Asia, and Europe. This article examines the migration pathways to and through the country, push and pull factors, and the impact of civil war on human movement.

It’s a conviction that was published in the November issue of The Journal of the American Dental Association and the basis for the October 2019 forum that Dr. Francisco Ramos-Gomez fostered, where dentists, physicians, nurses and public health and public policy experts proposed, discussed and recommended solutions for preventing early childhood caries through the lens of social justice, health equity and human rights.

ADA Practice Transitions, a service offered by the ADA focused on helping dentists make the process of joining or leaving a practice successful, is offering a free three-month trial.

OBJECTIVE

A recent publication questioned the integrity of insulin purchased from U.S. retail pharmacies. We sought to independently validate the method used, isotope dilution solid-phase extraction (SPE) liquid chromatography mass spectrometry (LC-MS), and expand analysis to two U.S. Pharmacopeia (USP) methods (high-performance LC with ultraviolet detection and LC-MS).

This event marked the launch of New York Times reporter Jason DeParle's book tracing the arc of migration as a phenomenon, witnessed through three decades observing a particular Filipino family moving from Manila to Texas. The conversation explored both the human and policy aspects of migration and development.

President Bush said last week that his thinking on the U.S. situation in Iraq was informed by an analogy: the October 2000 bombing of the USS Cole in Yemen. The lack of a sufficient American response to that and other al-Qaeda attacks, Bush said, led to the Sept. 11, 2001, attacks.

During this webinar, speakers discuss a MPI policy brief that explores the intersection of trauma and early childhood development, exploring how migration-related trauma and stressors can influence the wellbeing of young children of immigrants, and points to key opportunities for states to support, through early childhood and other programs.

This MPI webinar marks the release of a policy brief that explores program and policy opportunities to improve home visiting services for immigrant and DLL families currently underparticipating in these programs due to a lack of culturally and linguistically responsive programming and other barriers

OBJECTIVE

Previous studies suggested that childhood prediabetes may develop prior to obesity and be associated with relative insulin deficiency. We proposed that the insulin-deficient phenotype is genetically determined and tested this hypothesis by longitudinal modeling of insulin and glucose traits with diabetes risk genotypes in the EarlyBird cohort.

Marking the launch of New York Times reporter Jason DeParle's book tracing the arc of migration and its impacts through the life of an extended family of Filipino migrants over a three-decade period, from Manila and through Dubai to the Houston area, this conversation with MPI's Andrew Selee and the World Bank's Dilip Ratha explores migration at both a global and very personal level.

Marking a policy brief's release, this webinar explores the promise of home visiting services that support new parents alongside their infants and toddlers, plus strategies for improving how these programs work with immigrant and linguistically diverse families.

A Trump administration “public-charge” rule expected to be unveiled soon could create the potential to significantly reshape family-based legal immigration to the United States—and reduce arrivals from Asia, Latin America, and Africa—by imposing a de facto financial test that 40 percent of the U.S. born themselves would fail, as this commentary explains.

During this webinar, speakers provide an overview of an MPI policy brief that seeks to raise awareness of the intersection of trauma and early childhood development, and how U.S. early childhood programs could more effectively address this trauma in young children in refugee and immigrant households. The participants discuss efforts to integrate trauma-informed approaches into early childhood systems and how home visiting services can effectively address trauma and mental health through a two-generation approach.

During this time of lockdowns and quarantines, I know that many of you are looking for ways to pass the time, so allow me to suggest some entertaining and educational podcasts on the science of sex to help!

New York’s schools and colleges will remain shut through the end of the academic year because of the coronavirus pandemic, Gov. Andrew Cuomo said Friday.

New York’s schools and colleges will remain shut through the end of the academic year because of the coronavirus pandemic, Gov. Andrew Cuomo said Friday.

New York’s schools and colleges will remain shut through the end of the academic year because of the coronavirus pandemic, Gov. Andrew Cuomo said Friday.

Seek Academy in Newark, N.J., has added a social justice class for students in kindergarten through 4th grades to help them make sense of some of the most controversial issues of the day, including the "take the knee" debate.

The Rhode Island Department of Education and the nonprofit Learning Accelerator are teaming to develop a strategic plan and a communications strategy aimed at expanding blended learning.