[Frontiers in Bioscience 12, 282-296, January 1, 2007]
Gonadotropin-controlled mammal oocyte meiotic resumption
Meijia Zhang, Guoliang Xia, Bo Zhou and Chao Wang
College of Biological Sciences, China Agricultural University, Beijing 100094, PR China
TABLE OF CONTENTS
Fully grown mammalian oocytes resume meiosis as a consequence of rises in gonadotropin levels at the mid-cycle. The increase of cyclic adenosine 3',5'-monophosphate (cAMP) and the activation of protein kinase A (PKA), protein kinase C (PKC) and mitogen-activated protein kinase (MAPK) in cumulus cells are required for gonadotropins-induced meiotic resumption of oocytes. The various actions of cAMP activated by follicle-stimulating hormone (FSH) and luteinizing hormone (LH) also include meiosis activating sterol (MAS), gonadal steroid hormones and epidermal growth factor (EGF) network during meiotic resumption. Another second messenger guanosine 3',5'-cyclic monophosphate (cGMP) induced by nitric oxide (NO) or atrial natriuretic peptide (ANP) also mediates gonadotropins-controlled mammalian oocyte meiotic resumption. The different actions of FSH and LH on meiotic resumption are discussed. We hope to provide a framework to understand how the initial signals generated by gonadotropins-stimulation control the expression of genes required for meiotic resumption.