title: A Runx2/miR-3960/miR-2861 regulatory feedback loop during mouse osteoblast differentiation.
abstract: Our recent study showed that miR-2861 promotes osteoblast differentiation by targeting histone deacetylase 5, resulting in increased runt-related transcription factor 2 (Runx2) protein production. Here we identified another new microRNA (miRNA) (miR-3960) that played a regulatory role in osteoblast differentiation through a regulatory feedback loop with miR-2861. miR-3960 and miR-2861 were found clustered at the same loci. miR-3960 was transcribed during bone morphogenic protein 2 (BMP2)-induced osteogenesis of ST2 stromal cells. Overexpression of miR-3960 promoted BMP2-induced osteoblastogenesis. However, the inhibition of miR-3960 expression attenuated the osteoblastogenesis. Homeobox A2 (Hoxa2), a repressor of Runx2 expression, was confirmed to be a target of miR-3960. Electrophoretic mobility shift assay and chromatin immunoprecipitation experiments confirmed that Runx2 bound to the promoter of the miR-3960/miR-2861 cluster. Furthermore, overexpression of Runx2 induced miR-3960/miR-2861 transcription, and block of Runx2 expression attenuated BMP2-induced miR-3960/miR-2861 transcription. Here we report that miR-3960 and miR-2861, transcribed together from the same miRNA polycistron, both function in osteoblast differentiation through a novel Runx2/miR-3960/miR-2861 regulatory feedback loop. Our findings provide new insights into the roles of miRNAs in osteoblast differentiation.
authors.affiliation: Institute of Endocrinology and Metabolism, The Second Xiangya Hospital of Central South University, 139 Middle Renmin Road, Changsha, Hunan 410011, China.
authors.forename: Rong
authors.initials: R
authors.lastname: Hu
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.forename: Hui
authors.initials: H
authors.lastname: Li
authors.forename: Li
authors.initials: L
authors.lastname: Yang
authors.forename: Chao
authors.initials: C
authors.lastname: Chen
authors.forename: Zhu-Ying
authors.initials: ZY
authors.lastname: Xia
authors.forename: Li-Juan
authors.initials: LJ
authors.lastname: Guo
authors.forename: Hui
authors.initials: H
authors.lastname: Xie
authors.forename: Hou-De
authors.initials: HD
authors.lastname: Zhou
authors.forename: Xian-Ping
authors.initials: XP
authors.lastname: Wu
authors.forename: Xiang-Hang
authors.initials: XH
authors.lastname: Luo
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D015152:Blotting, Northern; D015153:Blotting, Western; D002454:Cell Differentiation / Q000235:genetics / Q000502:physiology; D002478:Cells, Cultured; D047369:Chromatin Immunoprecipitation; D019295:Computational Biology; D050659:Core Binding Factor Alpha 1 Subunit / Q000235:genetics / Q000378:metabolism*; D024202:Electrophoretic Mobility Shift Assay; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D035683:MicroRNAs / Q000235:genetics / Q000502:physiology*; D010006:Osteoblasts / Q000166:cytology* / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D050659:Core Binding Factor Alpha 1 Subunit; D018398:Homeodomain Proteins; C489833:Hoxa2 protein, mouse; D035683:MicroRNAs; D034741:RNA, Small Interfering