DOI: 10.3724/SP.J.1008.2012.00697

Academic Journal of Second Military Medical University (第二军医大学学报) 2012/32:7 PP.697-702

Role of a regulating protein in the upper stream of mTOR signaling pathway Rheb in adipocyte differentiation

Objective To observe the effect of Rheb, a regulating protein in the upper stream of mTOR signaling pathway, on adipocyte differentiation. Methods (1) The recombinant plasmid pCAG-Insulator-Rheb was constructed and injected into the embryo of B6 mouse to produce transgenic mouse over-expressing Rheb. (2) The mouse embryonic fibroblast cells (MEFs) were collected from Rheb transgenic mice on pregnancy day 13.5, and they were induced to differentiate into adipocytes after identified by PCR. (3) On differentiation day 12, the MEFs were subjected to Oil Red O staining and the contents of triglyceride in the MEFs were determined; moreover, the expression of special transcription factor PPARγ and C/EBPα was examined by real-time PCR, and all of the above parameters were used to assess the role of Rheb in the differentiation of adipocytes. Results We successfully constructed the transgenic mouse model over-expressing Rheb. We found that mouse over-expressing Rheb promoted adipogenesis in MEFs and increased the content of triglyceride in MEFs; moreover, the overexpression also greatly changed the results of Oil Red O staining and greatly promoted the expression of adipocyte specific transcript factor PPARγ and C/EBPα. Conclusion Over-expression of Rheb can promote the differentiation of MEFs into adipocytes.

Key words:Rheb,mTOR,adipocytes,cell differentiation

ReleaseDate:2014-07-21 16:39:11

Funds:National Natural Science Foundation of China(81170780).

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