Functional disparity between human PAWP and PLCζ in the generation of Ca2+ oscillations for oocyte activation.
Mol Hum Reprod
; 21(9): 702-10, 2015 Sep.
Article
em En
| MEDLINE
| ID: mdl-26116451
ABSTRACT
Mammalian oocyte activation is mediated by cytosolic calcium (Ca(2+)) oscillations initiated upon delivery of a putative 'sperm factor' by the fertilizing sperm. Previous studies suggest the identity of this sperm factor as the testis-specific phospholipase C-zeta (PLCζ). Recently, a post-acrosomal sheath WW domain-binding protein (PAWP) has been proposed as an alternative sperm factor candidate, following a report that human PAWP protein and cRNA elicited Ca(2+) oscillations in mouse and human oocytes. Those Ca(2+) oscillations were inhibited by a PAWP-derived peptide corresponding to a functional PPGY binding motif. Herein, using a series of human PAWP expression constructs, we demonstrate that both human PAWP protein and cRNA are, in our experiments, unable to elicit Ca(2+) release following microinjection into mouse oocytes. Parallel experiments performed with human PLCζ elicited the characteristic Ca(2+) oscillations present at mammalian fertilization, which produced oocyte activation and embryo development. Furthermore, sperm-induced Ca(2+) oscillations were not inhibited by the PAWP-derived PPGY peptide following in vitro fertilization or intracytoplasmic sperm injection. Thus, the functional disparity with PLCζ leads us to conclude that human PAWP is neither sufficient nor necessary for the Ca(2+) oscillations that initiate mammalian oocyte activation at fertilization.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Oócitos
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Proteínas de Transporte
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Sinalização do Cálcio
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Proteínas de Plasma Seminal
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Fosfoinositídeo Fosfolipase C
Limite:
Animals
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Female
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Humans
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Male
Idioma:
En
Revista:
Mol Hum Reprod
Assunto da revista:
BIOLOGIA MOLECULAR
/
MEDICINA REPRODUTIVA
Ano de publicação:
2015
Tipo de documento:
Article