160 research outputs found
It\u27s A Small World After All... At The Top: The View From Davos
This paper provides an intersectional portrait of the most powerful and influential group in the world: the global power elite, symbolized by the Davos man. An examination of this emerging class and its national and denationalized components includes analyses of the global economic and political system, concepts of the American power elite, hierarchal institutions of power, and the potential for elite gender parity
The metabolic syndrome- associated small G protein ARL15 plays a role in adipocyte differentiation and adiponectin secretion.
Common genetic variants at the ARL15 locus are associated with plasma adiponectin, insulin and HDL cholesterol concentrations, obesity, and coronary atherosclerosis. The ARL15 gene encodes a small GTP-binding protein whose function is currently unknown. In this study adipocyte-autonomous roles for ARL15 were investigated using conditional knockdown of Arl15 in murine 3T3-L1 (pre)adipocytes. Arl15 knockdown in differentiated adipocytes impaired adiponectin secretion but not adipsin secretion or insulin action, while in preadipocytes it impaired adipogenesis. In differentiated adipocytes GFP-tagged ARL15 localized predominantly to the Golgi with lower levels detected at the plasma membrane and intracellular vesicles, suggesting involvement in intracellular trafficking. Sequencing of ARL15 in 375 severely insulin resistant patients identified four rare heterozygous variants, including an early nonsense mutation in a proband with femorogluteal lipodystrophy and non classical congenital adrenal hyperplasia, and an essential splice site mutation in a proband with partial lipodystrophy and a history of childhood yolk sac tumour. No nonsense or essential splice site mutations were found in 2,479 controls, while five such variants were found in the ExAC database. These findings provide evidence that ARL15 plays a role in adipocyte differentiation and adiponectin secretion, and raise the possibility that human ARL15 haploinsufficiency predisposes to lipodystrophy
Exome-wide analysis of copy number variation shows association of the human leukocyte antigen region with asthma in UK Biobank
BackgroundThe role of copy number variants (CNVs) in susceptibility to asthma is not well understood. This is, in part, due to the difficulty of accurately measuring CNVs in large enough sample sizes to detect associations. The recent availability of whole-exome sequencing (WES) in large biobank studies provides an unprecedented opportunity to study the role of CNVs in asthma.MethodsWe called common CNVs in 49,953 individuals in the first release of UK Biobank WES using ClinCNV software. CNVs were tested for association with asthma in a stage 1 analysis comprising 7098 asthma cases and 36,578 controls from the first release of sequencing data. Nominally-associated CNVs were then meta-analysed in stage 2 with an additional 17,280 asthma cases and 115,562 controls from the second release of UK Biobank exome sequencing, followed by validation and fine-mapping.ResultsFive of 189 CNVs were associated with asthma in stage 2, including a deletion overlapping the HLA-DQA1 and HLA-DQB1 genes, a duplication of CHROMR/PRKRA, deletions within MUC22 and TAP2, and a duplication in FBRSL1. The HLA-DQA1, HLA-DQB1, MUC22 and TAP2 genes all reside within the human leukocyte antigen (HLA) region on chromosome 6. In silico analyses demonstrated that the deletion overlapping HLA-DQA1 and HLA-DQB1 is likely to be an artefact arising from under-mapping of reads from non-reference HLA haplotypes, and that the CHROMR/PRKRA and FBRSL1 duplications represent presence/absence of pseudogenes within the HLA region. Bayesian fine-mapping of the HLA region suggested that there are two independent asthma association signals. The variants with the largest posterior inclusion probability in the two credible sets were an amino acid change in HLA-DQB1 (glutamine to histidine at residue 253) and a multi-allelic amino acid change in HLA-DRB1 (presence/absence of serine, glycine or leucine at residue 11).ConclusionsAt least two independent loci characterised by amino acid changes in the HLA-DQA1, HLA-DQB1 and HLA-DRB1 genes are likely to account for association of SNPs and CNVs in this region with asthma. The high divergence of haplotypes in the HLA can give rise to spurious CNVs, providing an important, cautionary tale for future large-scale analyses of sequencing data
De novo point mutations in patients diagnosed with ataxic cerebral palsy
Cerebral palsy is commonly attributed to perinatal asphyxia. However, Schnekenberg et al. describe here four individuals with ataxic cerebral palsy likely due to de novo dominant mutations associated with increased paternal age. Therefore, patients with cerebral palsy should be investigated for genetic causes before the disorder is ascribed to asphyxi
Multi-Ancestry Genome-Wide Association Analyses Improve Resolution of Genes and Pathways Influencing Lung Function and Chronic Obstructive Pulmonary Disease Risk
Lung-function impairment underlies chronic obstructive pulmonary disease (COPD) and predicts mortality. In the largest multi-ancestry genome-wide association meta-analysis of lung function to date, comprising 580,869 participants, we identified 1,020 independent association signals implicating 559 genes supported by ≥2 criteria from a systematic variant-to-gene mapping framework. These genes were enriched in 29 pathways. Individual variants showed heterogeneity across ancestries, age and smoking groups, and collectively as a genetic risk score showed strong association with COPD across ancestry groups. We undertook phenome-wide association studies for selected associated variants as well as trait and pathway-specific genetic risk scores to infer possible consequences of intervening in pathways underlying lung function. We highlight new putative causal variants, genes, proteins and pathways, including those targeted by existing drugs. These findings bring us closer to understanding the mechanisms underlying lung function and COPD, and should inform functional genomics experiments and potentially future COPD therapies
Cadherin-10 maintains excitatory/inhibitory ratio through interactions with synaptic proteins
Appropriate excitatory/inhibitory (E/I) balance is essential for normal cortical function and is altered in some psychiatric disorders, including autism spectrum disorders (ASDs). Cell-autonomous molecular mechanisms that control the balance of excitatory and inhibitory synapse function remain poorly understood; no proteins that regulate excitatory and inhibitory synapse strength in a coordinated reciprocal manner have been identified. Using super-resolution imaging, electrophysiology, and molecular manipulations, we show that cadherin-10, encoded byCDH10within the ASD risk locus 5p14.1, maintains both excitatory and inhibitory synaptic scaffold structure in cultured cortical neurons from rats of both sexes. Cadherin-10 localizes to both excitatory and inhibitory synapses in neocortex, where it is organized into nanoscale puncta that influence the size of their associated PSDs. Knockdown of cadherin-10 reduces excitatory but increases inhibitory synapse size and strength, altering the E/I ratio in cortical neurons. Furthermore, cadherin-10 exhibits differential participation in complexes with PSD-95 and gephyrin, which may underlie its role in maintaining the E/I ratio. Our data provide a new mechanism whereby a protein encoded by a common ASD risk factor controls E/I ratios by regulating excitatory and inhibitory synapses in opposing directions.SIGNIFICANCE STATEMENTThe correct balance between excitatory/inhibitory (E/I) is crucial for normal brain function and is altered in psychiatric disorders such as autism. However, the molecular mechanisms that underlie this balance remain elusive. To address this, we studied cadherin-10, an adhesion protein that is genetically linked to autism and understudied at the cellular level. Using a combination of advanced microscopy techniques and electrophysiology, we show that cadherin-10 forms nanoscale puncta at excitatory and inhibitory synapses, maintains excitatory and inhibitory synaptic structure, and is essential for maintaining the correct balance between excitation and inhibition in neuronal dendrites. These findings reveal a new mechanism by which E/I balance is controlled in neurons and may bear relevance to synaptic dysfunction in autism.</jats:p
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