First Author | Duncan FE | Year | 2005 |
Journal | Dev Biol | Volume | 280 |
Issue | 1 | Pages | 38-47 |
PubMed ID | 15766746 | Mgi Jnum | J:98299 |
Mgi Id | MGI:3577813 | Doi | 10.1016/j.ydbio.2004.12.034 |
Citation | Duncan FE, et al. (2005) PAR-3 defines a central subdomain of the cortical actin cap in mouse eggs. Dev Biol 280(1):38-47 |
abstractText | The evolutionarily conserved partitioning defective (PAR) protein PAR-3 is pivotal for establishing and maintaining cell polarity. During mammalian oocyte maturation, the radially symmetric oocyte is transformed into a highly polarized metaphase II (MII)-arrested egg. We therefore examined several aspects of PAR-3 expression during oocyte maturation. We cloned two novel PAR-3 transcripts from an oocyte library that likely encode proteins of Mr = 73 K and 133 K that are phosphorylated during maturation. PAR-3, which is found throughout the GV-intact oocyte, becomes asymmetrically localized during meiosis. Following germinal vesicle breakdown, PAR-3 surrounds the condensing chromosomes and associates with the meiotic spindles. Prior to emission of the first and second polar bodies, PAR-3 is located within a central subdomain of the polarized actin cap, which overlies the spindle. This cortical PAR-3 localization depends on intact microfilaments. These results suggest a role for PAR-3 in establishing asymmetry in the egg and in defining the future site of polar body emission. |