title: Regulatory Role of miRNA-375 in Expression of BMP15/GDF9 Receptors and its Effect on Proliferation and Apoptosis of Bovine Cumulus Cells.
abstract: BACKGROUND
  Bone morphogenetic protein 15 (BMP15) and growth differentiation factor 9 (GDF9) are members of the transforming growth factor beta (TGF-β) superfamily. Through autocrine and paracrine mechanisms, these two factors can regulate cell differentiation, proliferation, and other functions in the ovary locally. Furthermore, GDF9 and BMP15 play vital roles in follicular growth, atresia, ovulation, fertilization, reproduction, and maintenance. Numerous studies have demonstrated a synergy between BMP15 and GDF9. Studies in humans and mice have indicated that the synergy between BMP15 and GDF9 is primarily mediated by the bone morphogenetic protein type II receptor (BMPR2). The BMP15/GDF9 heterodimer needs to bind to the BMPR2-ALK4/5/7-ALK6 receptor complex to activate the SMAD2/3 signaling pathway. However, it is not clear which genes mediate and regulate the effects of the BMP15/GDF9 proteins on bovine cumulus cells (CCs).
  
  
  METHODS
  Our earlier study showed that BMPR2 is a gene that is directly targeted and regulated by miR-375. Therefore, we designed and synthesized an miR-375 mimics/inhibitor and regulated BMPR2 expression in bovine CCs by the overexpression or inhibition of miR-375. After the overexpression or inhibition of miR-375, the apoptosis rate of bovine CCs was measured by flow cytometry; changes in critical gene expression were measured by RT-qPCR and western blot assays; and the proliferation of bovine CCs was measured by CCK-8 assay.
  
  
  RESULTS
  In bovine CCs, the overexpression of miR-375 resulted in decreased BMPR2 and ALK7 expression, whereas the inhibition of miR-375 caused increased BMPR2 and ALK7 expression. The overexpression of miR-375 attenuated the proliferation ability and significantly increased the apoptosis rate of bovine CCs, whereas the inhibition of miR-375 did not significantly change the proliferation ability or apoptosis rate.
  
  
  CONCLUSIONS
  BMPR2, a target of miR-375, is regulated by this molecule, thereby affecting expression of BMP15/GDF9 receptors, and the proliferation and apoptosis of bovine CCs.
authors.forename: Hongyan
authors.initials: H
authors.lastname: Chen
authors.forename: Chang
authors.initials: C
authors.lastname: Liu
authors.forename: Hao
authors.initials: H
authors.lastname: Jiang
authors.forename: Yan
authors.initials: Y
authors.lastname: Gao
authors.forename: Mingqiang
authors.initials: M
authors.lastname: Xu
authors.forename: Jiawei
authors.initials: J
authors.lastname: Wang
authors.forename: Siyuan
authors.initials: S
authors.lastname: Liu
authors.forename: Yao
authors.initials: Y
authors.lastname: Fu
authors.forename: Xulei
authors.initials: X
authors.lastname: Sun
authors.forename: Jiajun
authors.initials: J
authors.lastname: Xu
authors.forename: Jiabao
authors.initials: J
authors.lastname: Zhang
authors.forename: Lisheng
authors.initials: L
authors.lastname: Dai
mesh_terms: D030201:Activin Receptors, Type I / Q000235:genetics / Q000378:metabolism; D000818:Animals; D000070416:Antagomirs / Q000378:metabolism; D017209:Apoptosis; D055430:Bone Morphogenetic Protein 15 / Q000378:metabolism*; D052006:Bone Morphogenetic Protein Receptors, Type II / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D002417:Cattle; D049109:Cell Proliferation; D002470:Cell Survival; D002478:Cells, Cultured; D054885:Cumulus Cells / Q000166:cytology / Q000378:metabolism; D005260:Female; D055429:Growth Differentiation Factor 9 / Q000378:metabolism*; D035683:MicroRNAs / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D006080:Ovarian Follicle / Q000166:cytology; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000378:metabolism; D034622:RNA Interference; D012333:RNA, Messenger / Q000378:metabolism; D034741:RNA, Small Interfering / Q000378:metabolism; D051028:bcl-2-Associated X Protein / Q000235:genetics / Q000378:metabolism
chemical_list: D000070416:Antagomirs; D055430:Bone Morphogenetic Protein 15; D055429:Growth Differentiation Factor 9; D035683:MicroRNAs; D019253:Proto-Oncogene Proteins c-bcl-2; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D051028:bcl-2-Associated X Protein; D030201:Activin Receptors, Type I; D052006:Bone Morphogenetic Protein Receptors, Type II
keywords: Apoptosis; BMP15/GDF9; Cumulus cells; Proliferation; miRNA-375