MicroRNA-181a suppresses mouse granulosa cell proliferation by targeting activin receptor IIA

PLoS One. 2013;8(3):e59667. doi: 10.1371/journal.pone.0059667. Epub 2013 Mar 20.

Abstract

Activin, a member of the transforming growth factor-β superfamily, promotes the growth of preantral follicles and the proliferation of granulosa cells. However, little is known about the role of microRNAs in activin-mediated granulosa cell proliferation. Here, we reported a dose- and time-dependent suppression of microRNA-181a (miR-181a) expression by activin A in mouse granulosa cells (mGC). Overexpression of miR-181a in mGC suppressed activin receptor IIA (acvr2a) expression by binding to its 3'-untranslated region (3'-UTR), resulting in down-regulation of cyclin D2 and proliferating cell nuclear antigen expression, leading to inhibition of the cellular proliferation, while overexpression of acvr2a attenuated the suppressive effect of miR-181a on mGC proliferation. Consistent with the inhibition of acvr2a expression, miR-181a prevented the phosphorylation of the activin intracellular signal transducer, mothers against decapentaplegic homolog 2 (Smad2), leading to the inactivation of activin signaling pathway. Interestingly, we found that miR-181a expression decreased in ovaries of mice at age of 8, 12, and 21 days, as compared with that in ovaries of 3-day old mice, and its level was reduced in preantral and antral follicles of mice compared with that in primary ones. Moreover, the level of miR-181a in the blood of patients with premature ovarian failure was significantly increased compared with that in normal females. This study identifies an interplay between miR-181a and acvr2a, and reveals an important role of miR-181a in regulating granulosa cell proliferation and ovarian follicle development.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Activin Receptors, Type II / metabolism*
  • Activins / pharmacology*
  • Analysis of Variance
  • Animals
  • Blotting, Western
  • Cell Line
  • Cell Proliferation / drug effects*
  • Cyclin D2 / metabolism
  • DNA Primers / genetics
  • Dose-Response Relationship, Drug
  • Female
  • Granulosa Cells / cytology
  • Granulosa Cells / drug effects*
  • Granulosa Cells / metabolism
  • Humans
  • Luciferases
  • Mice
  • Mice, Inbred ICR
  • MicroRNAs / genetics
  • MicroRNAs / metabolism*
  • Microscopy, Fluorescence
  • Oligonucleotides / genetics
  • Ovarian Follicle / drug effects
  • Ovarian Follicle / growth & development*
  • Phosphorylation / drug effects
  • Proliferating Cell Nuclear Antigen / metabolism
  • Real-Time Polymerase Chain Reaction
  • Signal Transduction / drug effects*
  • Smad2 Protein / metabolism
  • Time Factors

Substances

  • Ccnd2 protein, mouse
  • Cyclin D2
  • DNA Primers
  • MicroRNAs
  • Oligonucleotides
  • Proliferating Cell Nuclear Antigen
  • Smad2 Protein
  • activin A
  • mirn181 microRNA, mouse
  • Activins
  • Luciferases
  • Activin Receptors, Type II
  • activin receptor type II-A

Grant support

This work was supported by a State Key Development Program of Basic Research of China Grant (973 Project No. 2010CB945104), the National Natural Science Foundation of China (No. 81070508, No. 30900727, No. 81070492, and No. 81170570), a special grant for principal investigators from the Health Department of Jiangsu Province (No. XK201102, No. LJ201102, and No. RC2011005) and the Scientific Research Foundation for Returned Overseas Chinese Scholars, State Education Ministry (2011-1139). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.