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Structure and regulation of phospholipase Cβ and ε at the membrane.

ABSTRACT: Phospholipase C (PLC) β and ε enzymes hydrolyze phosphatidylinositol (PI) lipids in response to direct interactions with heterotrimeric G protein subunits and small GTPases, which are activated downstream of G protein-coupled receptors (GPCRs) and receptor tyrosine kinases (RTKs). PI hydrolysis generates second messengers that increase the intracellular Ca²⁺ concentration and activate protein kinase C (PKC), thereby regulating numerous physiological processes. PLCβ and PLCε share a highly conserved core required for lipase activity, but use different strategies and structural elements to autoinhibit basal activity, bind membranes, and engage G protein activators. In this review, we discuss recent structural insights into these enzymes and the implications for how they engage membranes alone or in complex with their G protein regulators.

SUBMITTER: Muralidharan K

PROVIDER: S-EPMC7933103 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature

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Structure and regulation of phospholipase Cβ and ε at the membrane.

Muralidharan Kaushik K Van Camp Michelle M MM Lyon Angeline M AM

Chemistry and physics of lipids 20210107

Phospholipase C (PLC) β and ε enzymes hydrolyze phosphatidylinositol (PI) lipids in response to direct interactions with heterotrimeric G protein subunits and small GTPases, which are activated downstream of G protein-coupled receptors (GPCRs) and receptor tyrosine kinases (RTKs). PI hydrolysis generates second messengers that increase the intracellular Ca<sup>2+</sup> concentration and activate protein kinase C (PKC), thereby regulating numerous physiological processes. PLCβ and PLCε share a hi ...[more]

PMID: 33422547

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