Project description:Most information on molecular processes accompanying and driving adipocyte differentiation are derived from rodent models. Here, a comprehensive analysis of combined transcriptomic and proteomic alterations during adipocyte differentiation in Simpson–Golabi–Behmel Syndrome (SGBS) cells is provided. The SGBS cells are a well-established and the most widely applied cell model to study human adipocyte differentiation and cell biology. However, the molecular alterations during human adipocyte differentiation in SGBS cells have not yet been described in a combined analysis of proteome and transcriptome. Here a global proteomic and transcriptomic data set comprising relative quantification of a total of 14372 mRNA transcripts and 2641 intracellular and secreted proteins is presented. 1153 proteins and 313 genes are determined as differentially expressed between preadipocytes and the fully differentiated cells including adiponectin, lipoprotein lipase, fatty acid binding protein 4, fatty acid synthase, stearoyl-CoA desaturase, and apolipoprotein E and many other proteins from the fatty acid synthesis, amino acid synthesis as well as glucose and lipid metabolic pathways. Preadipocyte markers, such as latexin, GATA6, and CXCL6, are found to be significantly downregulated at the protein and transcript level. This multi-omics data set provides a deep molecular profile of adipogenesis and will support future studies to understand adipocyte function.
Project description:White adipocytes function as the major energy reservoir in humans by storing large amounts of triglycerides. Their dysfunction is associated with metabolic disorders. However, the mechanisms underlying cellular specialization during adipogenesis remain unknown. Here, we generated a spatiotemporal proteomic atlas of human adipogenesis to gain insights into cellular remodeling and the spatial reorganization of metabolic pathways to optimize cells for lipid accumulation. Our study highlights the coordinated regulation of protein localization and abundance during adipogenesis. More specifically, we identified a compartment-specific regulation of protein levels to reprogram branched chain amino acid and one-carbon metabolism to provide building blocks and reduction equivalents for lipid synthesis. Additionally, we identified C19orf12 as a differentiation induced adipocyte-specific lipid droplet (LD) protein, which interacts with the translocase of the outer membrane (TOM) complex of LD associated mitochondria and modulates adipocyte lipid storage. Overall, our study provides a comprehensive resource for understanding human adipogenesis and for future discoveries in the field.
Project description:Human bone marrow mesenchymal stromal cells are capable of limited self-renewal and multi-lineage differentiation in vitro. Several studies have demonstrated that microRNAs, post-transcriptional modifiers of protein expression, play crucial roles in the regulation of these complex processes. To gain knowledge regarding the role of microRNAs in human adipocyte regulation, we examined the microRNA expression profile of the immortalized human bone marrow-derived stromal cell line hMSC-Tert20. We identified 12 microRNAs that were differentially expressed during adipogenesis, of which several have previously been shown to play important roles in adipocyte biology. The expression of miR-155, miR-221 and miR-222 decreased during the adipogenic program, suggesting that they act as negative regulators of differentiation. Interestingly, adenovirus-mediated expression of either miR-155 alone or miR-221 plus miR-222 significantly inhibited adipogenesis and repressed induction of the master regulators C/EBP? and PPAR?. Our study provides the first experimental evidence that miR-155, miR-221 and miR-222 function in human adipocyte differentiation. The telomerase immortalized human bone marrow-derived stromal cell line hMSC-Tert20 was differentiated towards adipocytes, and total RNA was harvested at various time points (0, 8, 24, 32, 48 and 72 hours, and 7, 14 and 21 days). All hybridizations, except for 0h, 8h and 32h, were performed twice. The expression of each miRNA at a given time point was calculated as a ratio relative to its level on day 0. No dye swaps.
Project description:Ribosome biogenesis is a critical component of cell differentiation. Ribosome synthesis has been previously reported to be highly regulated at the transcriptional level, but less is known about its post-transcriptional regulation. Poly(A) tail length regulation is a hallmark of post-transcriptional regulation associated with transcript stability. Here we monitor poly(A) tail length changes at a transcriptome level during P19 differentiation. We found that poly(A) tail shortening occurs during cell differentiation only for transcript encoding for ribosomal proteins. These findings suggest a strong post-transcriptional regulation of ribosome biogenesis during differentiation.