Novel regulation of PLCζ activity via its XY-linker
نویسندگان
چکیده
The XY-linker region of somatic cell PLC (phospholipase)-β, -γ, -δ and -ε isoforms confers potent catalytic inhibition, suggesting a common auto-regulatory role. Surprisingly, the sperm PLCζ XY-linker does not mediate auto-inhibition. Unlike for somatic PLCs, the absence of the PLCζ XY-linker significantly diminishes both in vitro PIP2 (phosphatidylinositol 4,5-bisphosphate) hydrolysis and in vivo Ca2+-oscillation-inducing activity, revealing evidence for a novel PLCζ enzymatic mechanism.
منابع مشابه
Phospholipase Cζ binding to PtdIns(4,5)P2 requires the XY-linker region
Phospholipase C-zeta (PLCζ) is a strong candidate for the mammalian sperm-derived factor that triggers the Ca(2+) oscillations required for egg activation at fertilization. PLCζ lacks a PH domain, which targets PLCδ1 to the phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P(2)) substrate in the plasma membrane. Previous studies failed to detect PLCζ in the plasma membrane, hence the means of P...
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