Mammalian phospholipase Czeta induces oocyte activation from the sperm perinuclear matrix.
Dev Biol
; 274(2): 370-83, 2004 Oct 15.
Article
em En
| MEDLINE
| ID: mdl-15385165
ABSTRACT
Mammalian sperm-borne oocyte activating factor (SOAF) induces oocyte activation from a compartment that engages the oocyte cytoplasm, but it is not known how. A SOAF-containing extract (SE) was solubilized from the submembrane perinuclear matrix, a domain that enters the egg. SE initiated activation sufficient for full development. Microinjection coupled to tandem mass spectrometry enabled functional correlation profiling of fractionated SE without a priori assumptions about its chemical nature. Phospholipase C-zeta (PLCzeta) correlated absolutely with activating ability. Immunoblotting confirmed this and showed that the perinuclear matrix is the major site of 72-kDa PLCzeta. Oocyte activation was efficiently induced by 1.25 fg of sperm PLCzeta, corresponding to a fraction of one sperm equivalent (approximately 0.03). Immunofluorescence microscopy localized sperm head PLCzeta to a post-acrosomal region that becomes rapidly exposed to the ooplasm following gamete fusion. This multifaceted approach suggests a mechanism by which PLCzeta originates from an oocyte-penetrating assembly--the sperm perinuclear matrix--to induce mammalian oocyte activation at fertilization.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Oócitos
/
Fosfolipases Tipo C
/
Interações Espermatozoide-Óvulo
/
Espermatozoides
Limite:
Animals
/
Female
/
Humans
/
Male
Idioma:
En
Ano de publicação:
2004
Tipo de documento:
Article