title: MicroRNA-450a-3p represses cell proliferation and regulates embryo development by regulating Bub1 expression in mouse.
abstract: Bub1 is a critical component of the spindle assembly checkpoint (SAC) and closely linked to cell proliferation and differentiation. We previously found that spontaneous abortion embryos contained a low level of Bub1 protein but normal mRNA level, while the knockdown of Bub1 leads to abnormal numerical chromosomes in embryonic cells. Here, we investigated the mechanism through which governs the post-transcriptional regulation of Bub1 protein expression level. We first conducted bioinformatics analysis and identified eight putative miRNAs that may target Bub1. Luciferase reporter assay confirmed that miR-450a-3p can directly regulate Bub1 by binding to the 3'-untranslated region of Bub1 mRNA. We found that the overexpression of miR-450a-3p in mouse embryonic fibroblast (MEF) cells down-regulated Bub1 protein level, repressed cell proliferation, increased apoptosis and restricted most cells in G1 phase of the cell cycle. Furthermore, when the fertilized eggs were microinjected with miR-450a-3p mimics, the cleavage of zygotes was effectively suppressed. Our results strongly suggest that an abnormally decreased Bub1 level regulated by miRNAs may be implicated in the pathogenesis of spontaneous miscarriage. Therefore, the blockade of miR-450a-3p may be explored as a novel therapeutic strategy for preventing spontaneous miscarriages.
authors.affiliation: Key Laboratory for Clinical Laboratory Diagnostics of Education Ministry of China, Chongqing Medical University, People's Republic of China.
authors.forename: Min
authors.initials: M
authors.lastname: Luo
authors.forename: Yaguang
authors.initials: Y
authors.lastname: Weng
authors.forename: Jian
authors.initials: J
authors.lastname: Tang
authors.forename: Min
authors.initials: M
authors.lastname: Hu
authors.forename: Qiang
authors.initials: Q
authors.lastname: Liu
authors.forename: Fengbing
authors.initials: F
authors.lastname: Jiang
authors.forename: Dandan
authors.initials: D
authors.lastname: Yang
authors.forename: Chen
authors.initials: C
authors.lastname: Liu
authors.forename: Xiaoqin
authors.initials: X
authors.lastname: Zhan
authors.forename: Peipei
authors.initials: P
authors.lastname: Song
authors.forename: Huili
authors.initials: H
authors.lastname: Bai
authors.forename: Baolin
authors.initials: B
authors.lastname: Li
authors.forename: Qiong
authors.initials: Q
authors.lastname: Shi
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D015153:Blotting, Western; D049109:Cell Proliferation / Q000187:drug effects*; D019295:Computational Biology; D017931:DNA Primers / Q000235:genetics; D047108:Embryonic Development / Q000187:drug effects* / Q000502:physiology; D005786:Gene Expression Regulation / Q000187:drug effects*; D057809:HEK293 Cells; D006801:Humans; D008156:Luciferases; D059566:M Phase Cell Cycle Checkpoints / Q000187:drug effects / Q000502:physiology; D051379:Mice; D035683:MicroRNAs / Q000494:pharmacology*; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D017931:DNA Primers; C579613:MIRN450 microRNA, mouse; D035683:MicroRNAs; D008156:Luciferases; C584277:BUB1 protein, human; C584281:Bub1 protein, mouse; C090464:Bub1 spindle checkpoint protein; D017346:Protein Serine-Threonine Kinases