title: Mature miR-183, negatively regulated by transcription factor GATA3, promotes 3T3-L1 adipogenesis through inhibition of the canonical Wnt/β-catenin signaling pathway by targeting LRP6.
abstract: Differentiation of preadipocytes into adipocytes and the formation of the subsequent adipose tissue are critical for mammalian growth and development. The molecular mechanism relating to preadipocyte differentiation and adipogenesis from the perspective of miRNAs is not yet completely understood. Here we investigated whether miR-183 functioned in the differentiation process. Both gain-of-function and loss-of-function assays demonstrated that miR-183 positively regulated 3T3-L1 differentiation by enhancing the expression of adipogenic marker genes such as CCAAT/enhancer binding protein α (C/EBPα), peroxisome proliferator-activated receptor γ (PPARγ), adiponectin and fatty acid synthase (FAS), as well as the triglyceride content and accumulation of lipid droplets. Meanwhile, low-density lipoprotein receptor-related protein 6 (LRP6) was known to impair the canonical Wnt/β-catenin signaling pathway and thereafter reduce c-myc and nuclear β-catenin protein. We showed that the inhibition of LRP6 by siRNA promoted 3T3-L1 adipogenic differentiation and adipogenesis. Further analysis showed that mouse miR-183 gene had its own transcription unit containing CpG islands, transcription start site (TSS), coding sequence (CDS) and polyA signal within the flanking sequences 2500 nt upstream and downstream of mouse miR-183 in genome. The core promoter of miR-183 gene was identified and transcription factor GATA3 (GATA binding protein 3) significantly inhibited the expression of mature miR-183 by binding to its core promoter in vivo, as indicated by the chromatin immunoprecipitation (ChIP) assay. These results suggest that miR-183, though negatively regulated by transcription factor GATA3, enhances 3T3-L1 preadipocyte differentiation and adipogenesis through the inhibition of the canonical Wnt/β-catenin signaling pathway by targeting LRP6.
authors.affiliation: Key Laboratory of Swine Genetics and Breeding of Agricultural Ministry and Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, PR China; Hunan Institute of Animal & Veterinary Science, Changsha 410131, PR China.
authors.forename: Chen
authors.initials: C
authors.lastname: Chen
authors.affiliation: Key Laboratory of Swine Genetics and Breeding of Agricultural Ministry and Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, PR China.
authors.forename: Hong
authors.initials: H
authors.lastname: Xiang
authors.affiliation: Hunan Institute of Animal & Veterinary Science, Changsha 410131, PR China.
authors.forename: Ying-lin
authors.initials: YL
authors.lastname: Peng
authors.affiliation: Department of Animal Nutrition and Feed Science, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, PR China. Electronic address: pjhzau@163.com.
authors.forename: Jian
authors.initials: J
authors.lastname: Peng
authors.affiliation: Key Laboratory of Swine Genetics and Breeding of Agricultural Ministry and Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, PR China. Electronic address: jswhzau@163.com.
authors.forename: Si-wen
authors.initials: SW
authors.lastname: Jiang
mesh_terms: D020413:3' Untranslated Regions; D041721:3T3-L1 Cells; D050156:Adipogenesis; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D006224:Cricetinae; D050990:GATA3 Transcription Factor / Q000502:physiology*; D015870:Gene Expression; D060488:Low Density Lipoprotein Receptor-Related Protein-6 / Q000235:genetics* / Q000378:metabolism; D051379:Mice; D035683:MicroRNAs / Q000502:physiology*; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D034622:RNA Interference; D060449:Wnt Signaling Pathway
chemical_list: D020413:3' Untranslated Regions; D050990:GATA3 Transcription Factor; C494748:Gata3 protein, mouse; D060488:Low Density Lipoprotein Receptor-Related Protein-6; C555476:Lrp6 protein, mouse; D035683:MicroRNAs; C543802:Mirn183 microRNA, mouse
keywords: Adipogenesis; Canonical Wnt/β-catenin signaling; GATA3; Preadipocyte differentiation; miR-183