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Biology subjects

Chiarugi, D.

Publications and source records attributed to Chiarugi, D..

4 recordsLinked to original sources

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↗

Revealing grand-paternal programming of lipid metabolism using a novel computational tool

While the consequences of poor maternal diet on the offspring’s cardio-metabolic health have been studied in detail, the role of the father’s diet on the health of his offspring is poorly understood. We used a known mouse model to establish the impact of an isocaloric paternal low-protein high-carbohydrate diet on the offspring’s lipid metabolism. Detailed lipid profiles were acquired from F1 neonate (3 weeks), F1 adult (16 weeks) and F2 neonate male and female offspring, in serum, liver, brain, heart and abdominal adipose tissues by Mass Spectrometry and Nuclear Magnetic Resonance. Using a purpose-built computational tool for analysing lipid metabolism as a network, we characterised the number, type and abundance of lipid variables in and between tissues (Lipid Traffic Analysis), finding a variety of alterations associated with paternal diet. These elucidate a mechanism for the defective physiological behaviour of systems at risk of cardio-metabolic disease.Competing Interest StatementThe authors have declared no competing interest.View Full Text

developmental biology↗

A workbench for the translational control of gene expression

Ribosome profiling (Ribo-seq profiling) is the most advanced tool to study the translational control of gene expression. Unfortunately, the resolution of this cutting edge technique is severely limited by a low signal to noise ratio. To tackle this issue, we introduce here a newly designed statistical method for the identification of reproducible Ribo-seq profiles. In the case of E. coli, the analysis of 2238 Ribo-seq profiles across 9 independent datasets revealed that only 11 profiles are significantly reproducible. A subsequent data quality check led us to identify one outgroup dataset. By ruling it out, the number of highly reproducible profiles could be raised to 49. Despite its surprisingly small size, this set represents a reliable workbench to both assess the quality of the data and study the factors that influence the translation process.

bioinformatics↗

Comparison of human and murine enteroendocrine cells by transcriptomic and peptidomic profiling

Enteroendocrine cells (EECs) produce hormones that regulate food absorption, insulin secretion and appetite. Both EECs and their peptide products are foci of drug discovery programmes for diabetes and obesity. We compared the human and mouse EEC transcriptome and peptidome to validate mouse as a model of the human enteroendocrine axis. We present the first RNA sequencing analysis of human EECs, and demonstrate strong correlation with mouse, although with outliers including some low abundance G-protein coupled receptors. Liquid chromatography mass spectrometry (LC-MS) identified peptide hormone gradients along the human and mouse gut that should enhance progress in gut physiology and therapeutics.

cell biology↗