Premium
Cows are not mice: The role of cyclic AMP, phosphodiesterases, and adenosine monophosphate‐activated protein kinase in the maintenance of meiotic arrest in bovine oocytes
Author(s) -
BilodeauGoeseels Sylvie
Publication year - 2011
Publication title -
molecular reproduction and development
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.745
H-Index - 105
eISSN - 1098-2795
pISSN - 1040-452X
DOI - 10.1002/mrd.21337
Subject(s) - biology , oocyte , phosphodiesterase , meiosis , protein kinase a , microbiology and biotechnology , cyclic adenosine monophosphate , adenosine monophosphate , in vitro maturation , maturation promoting factor , adenosine , kinase , endocrinology , embryo , genetics , gene , biochemistry , enzyme , cell cycle , receptor , cyclin dependent kinase 1
Abstract Meiotic maturation in mammalian oocytes is initiated during fetal development, and is then arrested at the dictyate stage – possibly for several years. Oocyte meiosis resumes in preovulatory follicles in response to the lutenizing hormone (LH) surge or spontaneously when competent oocytes are removed from follicles and cultured. The mechanisms involved in meiotic arrest and resumption in bovine oocytes are not fully understood, and several studies point to important differences between oocytes from rodent and livestock species. This paper reviews earlier and contemporary studies on the effects of cAMP‐elevating agents and phosphodiesterase (PDE) enzyme inhibitors on the maintenance of meiotic arrest in bovine oocytes in vitro. Contrary to results obtained with mouse oocytes, bovine oocyte meiosis is inhibited by activators of the energy sensor adenosine monophosphate‐activated protein kinase (AMPK, mammalian gene PRKA), which is activated by AMP, the degradation product of cAMP. It is not clear whether or not the effects were due to AMPK activation, and they may depend on culture conditions. Evidence suggests that other signaling pathways (for example, the cGMP/nitric oxide pathway) are involved in bovine oocyte meiotic arrest, but further studies are needed to understand the interactions between the signaling pathways that lead to maturation promoting factor (MPF) being inactive or active. An improved understanding of the mechanisms involved in the control of bovine oocyte meiosis will facilitate better control of the process in vitro, resulting in increased developmental competence and increased efficiency of in vitro embryo production procedures. Mol. Reprod. Dev. 78:734–743, 2011. © 2011 Wiley Periodicals, Inc.