title: miR-145 and miR-143 regulate odontoblast differentiation through targeting Klf4 and Osx genes in a feedback loop.
abstract: Dentin tissue is derived from mesenchymal cells induced into the odontoblast lineage. The differentiation of odontoblasts is a complex process regulated by several transcriptional factor signaling transduction pathways. However, post-translational regulation of these factors during dentinogenesis remains unclear. To further explore the mechanisms, we investigated the role of microRNA (miRNA) during odontoblast differentiation. We profiled the miRNA expression pattern during mouse odontoblast differentiation using a microarray assay and identified that miR-145 and miR-143 were down-regulated during this process. In situ hybridization verified that the two miRNAs were gradually decreased during mouse odontoblast differentiation. Loss-of-function and gain-of-function experiments revealed that down-regulation of miR-145 and miR-143 could promote odontoblast differentiation and increased Dspp and Dmp1 expression in mouse primary dental pulp cells and vice versa. We found that miR-145 and miR-143 controlled odontoblast differentiation through several mechanisms. First, KLF4 and OSX bind to their motifs in Dspp and Dmp1 gene promoters and up-regulate their transcription thereby inducing odontoblast differentiation. The miR-145 binds to the 3'-UTRs of Klf4 and Osx genes, inhibiting their expression. Second, KLF4 repressed miR-143 transcription by binding to its motifs in miR-143 regulatory regions as detected by ChIP assay and dual luciferase reporter assay. Third, miR-143 regulates odontoblast differentiation in part through miR-145 pathway. Taken together, we for the first time showed that the miR-143 and miR-145 controlled odontoblast differentiation and dentin formation through KLF4 and OSX transcriptional factor signaling pathways.
authors: State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory for Oral Biomedicine of Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan 430079, China.
authors: Huan
authors: H
authors: Liu
authors: Heng
authors: H
authors: Lin
authors: Li
authors: L
authors: Zhang
authors: Qin
authors: Q
authors: Sun
authors: Guohua
authors: G
authors: Yuan
authors: Lu
authors: L
authors: Zhang
authors: Shuo
authors: S
authors: Chen
authors: Zhi
authors: Z
authors: Chen
mesh_terms: D020413:3' Untranslated Regions; D020816:Amino Acid Motifs; D000818:Animals; D002454:Cell Differentiation; D002460:Cell Line; D047369:Chromatin Immunoprecipitation; D003804:Dentin / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D017403:In Situ Hybridization; D000090062:Kruppel-Like Factor 4; D051741:Kruppel-Like Transcription Factors / Q000378:metabolism*; D051379:Mice; D035683:MicroRNAs / Q000378:metabolism*; D009804:Odontoblasts / Q000166:cytology / Q000378:metabolism*; D020411:Oligonucleotide Array Sequence Analysis; D015398:Signal Transduction; D000076182:Sp7 Transcription Factor; D013997:Time Factors; D014070:Tooth / Q000196:embryology; D014157:Transcription Factors / Q000378:metabolism*
chemical_list: D020413:3' Untranslated Regions; C000715468:Klf4 protein, mouse; D000090062:Kruppel-Like Factor 4; D051741:Kruppel-Like Transcription Factors; C543499:MIRN145a microRNA, mouse; D035683:MicroRNAs; C532884:MIRN143 microRNA, mouse; D000076182:Sp7 Transcription Factor; C479466:Sp7 protein, mouse; D014157:Transcription Factors