Premium
Journey of oocyte from metaphase‐I to metaphase‐II stage in mammals
Author(s) -
Sharma Alka,
Tiwari Meenakshi,
Gupta Anumegha,
Pandey Ashutosh N.,
Yadav Pramod K.,
Chaube Shail K.
Publication year - 2018
Publication title -
journal of cellular physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.529
H-Index - 174
eISSN - 1097-4652
pISSN - 0021-9541
DOI - 10.1002/jcp.26467
Subject(s) - metaphase , microbiology and biotechnology , mitosis , oocyte , biology , maturation promoting factor , meiosis , oocyte activation , anaphase , cdc42 , polar body , cell division , cell cycle , meiosis ii , protein kinase a , cytokinesis , signal transduction , kinase , cyclin , genetics , cell , chromosome , embryo , gene
In mammals, journey from metaphase‐I (M‐I) to metaphase‐II (M‐II) is important since oocyte extrude first polar body (PB‐I) and gets converted into haploid gamete. The molecular and cellular changes associated with meiotic cell cycle progression from M‐I to M‐II stage and extrusion of PB‐I remain ill understood. Several factors drive oocyte meiosis from M‐I to M‐II stage. The mitogen‐activated protein kinase3/1 (MAPK3/1), signal molecules and Rho family GTPases act through various pathways to drive cell cycle progression from M‐I to M‐II stage. The down regulation of MOS/MEK/MAPK3/1 pathway results in the activation of anaphase‐promoting complex/cyclosome (APC/C). The active APC/C destabilizes maturation promoting factor (MPF) and induces meiotic resumption. Several signal molecules such as, c‐Jun N‐terminal kinase (JNK2), SENP3, mitotic kinesin‐like protein 2 (MKlp2), regulator of G‐protein signaling (RGS2), Epsin2, polo‐like kinase 1 (Plk1) are directly or indirectly involved in chromosomal segregation. Rho family GTPase is another enzyme that along with cell division cycle (Cdc42) to form actomyosin contractile ring required for chromosomal segregation. In the presence of origin recognition complex (ORC4), eccentrically localized haploid set of chromosomes trigger cortex differentiation and determine the division site for polar body formation. The actomyosin contractile activity at the site of division plane helps to form cytokinetic furrow that results in the formation and extrusion of PB‐I. Indeed, oocyte journey from M‐I to M‐II stage is coordinated by several factors and pathways that enable oocyte to extrude PB‐I. Quality of oocyte directly impact fertilization rate, early embryonic development, and reproductive outcome in mammals.