Novel regulation of PLC? activity via its XY-linker.
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ABSTRACT:
SUBMITTER: Nomikos M
PROVIDER: S-EPMC3195331 | biostudies-literature | 2011 Sep
REPOSITORIES: biostudies-literature
Publications
Novel regulation of PLCζ activity via its XY-linker.
Nomikos Michail M Elgmati Khalil K Theodoridou Maria M Georgilis Athena A Gonzalez-Garcia J Raul JR Nounesis George G Swann Karl K Lai F Anthony FA
The Biochemical journal 20110901 3
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. ...[more]
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