PPARγ enhanced Adiponectin polymerization and trafficking by promoting RUVBL2 expression during adipogenic differentiation

Adipocyte differentiation is an essential part of adipose tissue development, and is closely related to obesity and obesity-related diseases. In this study, we found that the expression of PPAR gamma, RUVBL2 and Adiponectin were concurrently obviously increased in the 5th-7th day of 3T3-L1 cell differentiation. PPAR gamma overexpression or the PPAR gamma activator facilitated Adiponectin trafficking and secretion and upregulated RUVBL2 expression as well as AS160 phosphorylation during adipogenic differentiation of 3T3-L1 cells. Consistently RUVBL2 overexpression also enhanced the polymerization and secretion of Adiponectin, in contrast, RUVBL2 knockdown reduced Adiponectin secretion. Further, PPAR gamma significantly enhanced RUVBL2 promoter activity and transcription. The progressive deletions and mutations of RUVBL2 promoter for PPAR gamma binding sites suggested that the PPAR gamma binding motif situated at - 804/ - 781 bp is an essential component required for RUVBL2 promoter activity. Chromatin immunoprecipitation (ChIP) assays determined that PPAR gamma can directly interact with the RUVBL2 promoter DNA. Taken together, these data suggest that PPAR gamma promotes the expression, polymerization and secretion of Adiponectin by activating RUVBL2 transcriptionally, which accelerates 3T3-L1 cell differentiation.

Automated summary

The study demonstrates that PPAR gamma promotes the expression, polymerization, and secretion of Adiponectin by activating RUVBL2 transcriptionally, which accelerates the differentiation of 3T3-L1 cells.