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Biology subjects

Kentistou, K. A.

Publications and source records attributed to Kentistou, K. A..

7 recordsLinked to original sources

Human HYPOMAP: A comprehensive spatio-cellular map of the human hypothalamus

The hypothalamus is a brain region that plays a key role in coordinating fundamental biological functions. However, our understanding of the underlying cellular components and circuitry, have, until recently, emerged primarily from rodent studies. Here, we combine a single-nucleus sequencing database of 433,369 human hypothalamic cells, with spatial transcriptomics, to present a comprehensive spatio-cellular transcriptional map of the human hypothalamus, the HYPOMAP. Analysing hypothalamic leptin melanocortin pathway neuronal populations that play a role in appetite control, we identify spatially distinct populations of arcuate nucleus POMC and AGRP neurons, and their receptors MC3R and MC4R. Next, we map the cells expressing incretin receptors, targets of the new generation of anti-obesity medications, and uncover transcriptionally distinct GLP1R and GIPR-expressing cellular populations. Finally, out of the 458 hypothalamic cell types in HYPOMAP, we find 182 neuronal clusters are significantly enriched in expression of BMI GWAS genes. This enrichment is driven by 375 effector genes, with rare deleterious variants in 6 of these; MC4R, PCSK1, POMC, CALCR, BSN and CORO1A, the last of which has previously not been linked to obesity; being significantly associated with changes in BMI at the population level. Thus, the HYPOMAP provides a detailed atlas of the human hypothalamus in a spatial context, and serves as an important resource to identify novel druggable targets for treating a wide range of conditions, including reproductive, circadian, and metabolic disorders.

neuroscience↗

Genome-wide analysis of promoter contacts identifies novel regulators of late-stage adipogenesis

Adipogenesis is a multi-stage process essential for healthy fat storage and metabolic regulation. While early regulatory mechanisms are well characterized, the control of late-stage adipocyte differentiation remains poorly understood. Integrating CAGE-seq, promoter capture Hi-C, and a high-throughput siRNA screen of druggable genes, we report here that chromatin architecture rewiring promotes gene regulation changes essential for terminal adipogenesis. We identified nine clusters of dynamic promoter-anchored chromosomal interactions, many involving distal enhancers. Functional screening of genes engaged in these interactions revealed 19 novel regulators of late adipogenesis, including proteins with peptidase and ubiquitin ligase activity. Human genetic variant-to-gene mapping, coupled with cross-species chromatin interaction and synteny analyses, highlighted new gene-trait associations relevant to lipid traits (FXYD5, LAP3, SGPP1) and type 2 diabetes (FBXO17, FN3KRP, ZFAND6, TTC3). Our findings define the 3D gene regulatory landscape of late adipogenesis. The molecular links uncovered here provide mechanistic insight into metabolic disease risk and potential interventions.

genetics↗

A multiparametric anti-aging CRISPR screen uncovers a role for BAF in protein translation

Progeria syndromes are very rare, incurable premature aging conditions recapitulating most aging features. Here, we report the first whole genome, multiparametric CRISPR anti-aging screen, identifying 43 new genes that can reverse multiple aging phenotypes in progeria. The screen was implemented in fibroblasts from Nestor- Guillermo Progeria Syndrome (NGPS) patients, carrying a homozygous p.Ala12Thr mutation in barrier-to-autointegration factor (BAF A12T). The hits were enriched for genes involved in protein translation, protein and RNA transport and osteoclast formation. We further confirmed that BAF A12T drives increased protein translation and translational errors that could directly contribute to premature aging in patients. This work has highlighted the power of multiparametric whole genome synthetic rescue screens to identify new anti-aging genes and uncover novel biology behind progeria-associated cellular dysfunction. One-Sentence SummaryA whole genome multiparametric screen in progeria identifies new pathways that can reverse cellular aging phenotypes.

molecular biology↗

Maternal obesity programs hypothalamic miR-505-5p expression in mouse offspring and impacts hypothalamic fatty acid sensing

In utero exposure to maternal obesity programs increased obesity risk. Animal models show that programmed offspring obesity is preceded by hyperphagia, but the mechanisms that mediate these changes are unknown. Using a mouse model of maternal obesity, we observed increased intake of a high-fat diet in offspring of obese mothers that precedes the development of obesity. Through small RNA sequencing, we identified programmed overexpression of hypothalamic miR-505-5p that is established in the fetus, lasts to adulthood and is maintained in hypothalamic neural progenitor cells cultured in vitro. Metabolic hormones and long-chain fatty acids associated with obesity increase miR-505-5p expression in hypothalamic neurons in vitro. We demonstrate that targets of miR-505-5p are enriched in fatty acid metabolism pathways and over-expression of miR-505-5p decreased neuronal fatty acid metabolism in vitro. miR-505-5p targets are associated with increased BMI in human genetic studies. Intra-cerebroventricular injection of miR-505-5p in wild-type mice increased high-fat diet intake, mimicking the phenotype observed in offspring exposed to maternal obesity. Conversely, maternal exercise intervention in an obese mouse pregnancy rescued the programmed increase of hypothalamic miR-505-5p in offspring of obese dams and reduced high-fat diet intake to control offspring levels. This study identifies a novel mechanism by which maternal obesity programs obesity in offspring via increased intake of high-fat foods.

neuroscience↗

Using genetics to disentangle the complex relationship between food choices and health status

Despite food choices being one of the most important factors influencing health, efforts to identify individual food groups and dietary patterns that cause disease have been challenging, with traditional nutritional epidemiological approaches plagued by biases and confounding. After identifying 302 individual genetic determinants of dietary intake in 445,779 individuals in the UK Biobank study, we develop a statistical genetics framework that enables us, to directly assess the impact of food choices on health outcomes. We show that the biases which affect observational studies extend also to GWAS, genetic correlations and causal inference through genetics, which can be corrected by applying our methods. Finally, by applying Mendelian Randomization approaches to the corrected results we identify some of the first robust causal associations between eating patterns and cancer, heart disease, obesity, and several other health related risk factors, distinguishing between the effects of specific foods or dietary patterns.

genetics↗

Genome-wide association and functional studies identify 46 novel loci for alcohol consumption and suggest common genetic mechanisms with neuropsychiatric disorders

Excessive alcohol consumption is one of the main causes of death and disability worldwide. Alcohol consumption is a heritable complex trait. We conducted a genome-wide association study (GWAS) of alcohol use in ~480,000 people of European descent to decipher the genetic architecture of alcohol intake. We identified 46 novel, common loci, and investigated their potential functional significance using magnetic resonance imaging data, gene expression and behavioral studies in Drosophila. Our results identify new genetic pathways associated with alcohol consumption and suggest common genetic mechanisms with several neuropsychiatric disorders including schizophrenia.

genetics↗

New genetic signals for lung function highlight pathways and pleiotropy, and chronic obstructive pulmonary disease associations across multiple ancestries

Reduced lung function predicts mortality and is key to the diagnosis of COPD. In a genome-wide association study in 400,102 individuals of European ancestry, we define 279 lung function signals, one-half of which are new. In combination these variants strongly predict COPD in deeply-phenotyped patient populations. Furthermore, the combined effect of these variants showed generalisability across smokers and never-smokers, and across ancestral groups. We highlight biological pathways, known and potential drug targets for COPD and, in phenome-wide association studies, autoimmune-related and other pleiotropic effects of lung function associated variants. This new genetic evidence has potential to improve future preventive and therapeutic strategies for COPD.

genomics↗