GSE147687 Insulin-Induced Serine 22 Phosphorylation of Retinoid X Receptor Alpha Is Dispensable For Adipogenesis in Brown Adipocytes

Contributors : Jacob Ardenkj ær-Larsen ; Kaja Rupar ; Goda Sinkevičiūtė ; Patricia S Petersen ; Julia Villarroel ; Morthen Lundh ; Romain Barrès ; Atefeh Rabiee ; Brice EmanuelliSeries Type : Expression profiling by high throughput sequencingOrganism : Mus musculusInsulin action initiates a series of phosphorylation events regulating cellular differentiation, growth and metabolism. We have previously discovered, in a mass spectrometry-based phosphoproteomic study, that insulin/IGF-1 signaling induces phosphorylation of retinoid x receptor alpha (RXR α) at S22 in mouse brown pre-adipocytes. Here, we show that insulin induces the phosphorylation of RXRα at S22 in both brown precursor and mature adipocytes through a pathway involving ERK, downstream of IRS-1 and -2. We also found that RXRα S22 phosphorylation is promoted by insulin and upon re- feeding in brown adipose tissue in vivo, and that insulin-stimulated S22 phosphorylation of RXRα is dampened by diet-induced obesity. We used Rxra knockout cells re-expressing wild type (WT) or S22A non-phosphorylatable forms of RXRα to further characterize the role of S22 in brown adipocytes. Kno ckout of Rxra in brown pre-adipocytes resulted in decreased lipid accumulation and adipogenic gene expression during differentiation, and re-expression of RxraWT alleviated these effects. However, we observed no significant difference in cells re-expressing the RxraS22A mutant as compared with the c ells re-expressing RxraWT. F...
Source: GEO: Gene Expression Omnibus - Category: Genetics & Stem Cells Tags: Expression profiling by high throughput sequencing Mus musculus Source Type: research