title: Inhibitory effect of microRNA-24 on fatty acid-binding protein expression on 3T3-L1 adipocyte differentiation.
abstract: We examined the effect of microRNAs on 3T3-L1 adipocyte differentiation and expression of adipocyte-specific gene fatty acid-binding protein 4 (FABP4). We screened and identified adipo-related microRNAs during 3T3-L1 adipocyte differentiation with a microRNA microarray. High expression plasmids of miR-24 and miR-21 were constructed and transfected into 3T3-L1 preadipocytes by lipofectamine. The effects of miR-24 and miR-21 on 3T3-L1 adipocyte differentiation were observed, and the protein and mRNA expression levels of FABP4 and AP-1 were determined. The expression profiles of microRNAs significantly changed during 3T3-L1 adipocyte differentiation. The expression of 33 microRNAs was downregulated, among which downregulation of miR-24 was the most extensive. There were 17 microRNAs with upregulated expression; the highest levels were found for miR-21. miR-24 significantly inhibited 3T3-L1 adipocyte differentiation and maturity, while miR-21 had no significant effect. In addition, miR-24 significantly inhibited the expression of FABP4, while it upregulated AP-1 expression, but had no effect on the level of FABP4 mRNA. miR-21 had no effect on FABP4 protein and mRNA expression. AP-1 silencing could, at least partially, reverse the inhibitory effect of miR-24 on FABP4 expression. We conclude that microRNA expression profiles change significantly during 3T3- L1 adipocyte differentiation and that miR-24 plays an important role in regulating adipocyte differentiation and FABP4 expression. The mechanism involved may be the upregulation of AP-1.
authors.affiliation: Department of Radiotherapy, First Affiliated Hospital of Guangxi Medical University, Nanning, China.
authors.forename: M
authors.initials: M
authors.lastname: Kang
authors.forename: L M
authors.initials: LM
authors.lastname: Yan
authors.forename: Y M
authors.initials: YM
authors.lastname: Li
authors.forename: W Y
authors.initials: WY
authors.lastname: Zhang
authors.forename: H
authors.initials: H
authors.lastname: Wang
authors.forename: A Z
authors.initials: AZ
authors.lastname: Tang
authors.forename: H S
authors.initials: HS
authors.lastname: Ou
mesh_terms: D041721:3T3-L1 Cells; D017667:Adipocytes / Q000166:cytology* / Q000378:metabolism*; D000818:Animals; D002454:Cell Differentiation / Q000235:genetics*; D050556:Fatty Acid-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D051379:Mice; D035683:MicroRNAs / Q000235:genetics*; D034622:RNA Interference; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D018808:Transcription Factor AP-1 / Q000235:genetics / Q000378:metabolism
chemical_list: C493411:Fabp4 protein, mouse; D050556:Fatty Acid-Binding Proteins; C531950:MIRN21 microRNA, mouse; D035683:MicroRNAs; C529080:Mirn24 microRNA, mouse; D012333:RNA, Messenger; D018808:Transcription Factor AP-1