title: Expression of pref-1/dlk-1 is regulated by microRNA-143 in 3T3-L1 cells.
abstract: Preadipocyte factor 1 (Pref-1), also known as a delta-like 1 protein, is a transmembrane and secreted protein containing the epidermal growth factor-like repeat. Pref-1 inhibits adipocyte differentiation by activating the ERK1/2 pathway. MicroRNAs, a new class of small noncoding RNAs of 20-24 nucleotides, act as negative regulators of gene expression and result in mRNA degradation or translational repression. MicroRNA-143 (miR-143) is known to induce adipocyte differentiation; however, miR-143 targets in the regulation of adipocyte differentiation remain unknown. In this study, we investigated whether pref-1 is a miR-143 target to regulate adipogenesis. After the induction of adipocyte differentiation the level of miR-143 was increased, whereas the expression of pref-1 mRNA was decreased. The pref-1 protein level was also down-regulated in preadipocytes ectopically expressing miR-143, and recovered by miR-143 inhibitor. The binding region for miR-143 was predicted to be located between positions 247 and 252 in the 3'-UTR of pref-1. The luciferase activity of the vector containing the wild-type 3'-UTR of pref-1 was decreased by 65 % in cells transfected with miR-143 mimic compared to that of the corresponding control. In contrast, the activity of the pref-1 mutant cells was not affected by the treatment with miR-143 mimic. The ectopic expression of miR-143 mimic suppressed the phosphorylation of ERK1/2 induced by pref-1 in 3T3-L1 cells. However, the suppressed phosphorylation was restored by miR-143 inhibitor. Taken together, these data suggest that miR-143 promotes adipogenesis by directly modulating the pref-1 expression in adipocytes.
authors.affiliation: Department of Biology, Research Institute for Basic Science, Kyung Hee University, Seoul, 130-701, Korea.
authors.forename: Yoon-Jin
authors.initials: YJ
authors.lastname: Kim
authors.forename: Tae Sun
authors.initials: TS
authors.lastname: Min
authors.forename: Kang-Seok
authors.initials: KS
authors.lastname: Seo
authors.forename: Sang Hoon
authors.initials: SH
authors.lastname: Kim
mesh_terms: D020413:3' Untranslated Regions; D041721:3T3-L1 Cells; D017667:Adipocytes / Q000166:cytology / Q000378:metabolism; D050156:Adipogenesis / Q000235:genetics; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D002135:Calcium-Binding Proteins; D002454:Cell Differentiation / Q000235:genetics; D015870:Gene Expression; D005786:Gene Expression Regulation; D036341:Intercellular Signaling Peptides and Proteins / Q000235:genetics*; D051379:Mice; D035683:MicroRNAs / Q000737:chemistry / Q000235:genetics*; D034622:RNA Interference; D012333:RNA, Messenger / Q000737:chemistry / Q000235:genetics; D014162:Transfection
chemical_list: D020413:3' Untranslated Regions; D002135:Calcium-Binding Proteins; C512925:Dlk1 protein, mouse; D036341:Intercellular Signaling Peptides and Proteins; D035683:MicroRNAs; C532884:MIRN143 microRNA, mouse; D012333:RNA, Messenger