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bioRxiv · 10.64898/2026.07.20.739664

Anionic lipids regulate PLCβ membrane recruitment

Crawford, M. A.·Bennett, M. B.·Qin, Y.·Cano, K. E.·Gonzalez, T. G.·Mojidra, R.·Falzone, M. E.
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Abstract

Phospholipase C-{beta} (PLC{beta}) enzymes are essential effectors of G protein-coupled receptor signaling that hydrolyze phosphatidylinositol 4,5-bisphosphate (PIP2) at the plasma membrane to generate the second messengers inositol trisphosphate and diacylglycerol. PLC{beta}s play essential roles in diverse physiological processes, including cardiac and neuronal function, macrophage activation, and the pathogenesis of diseases such as hypertrophic cardiomyopathy. PLC{beta} enzymes are unique in that they are aqueous-soluble and must partition onto the membrane surface to access their substrate, making membrane association a critical regulatory step. For example, we recently demonstrated that G{beta}{gamma} activates PLC{beta} by membrane recruitment and orientation of the catalytic core on the membrane surface. Although PLC{beta} membrane recruitment is required for function, the molecular determinants governing this process remain incompletely understood. Using a quantitative membrane partitioning assay, we show that robust membrane association of PLC{beta} requires anionic phospholipids, whereas polar phospholipids cannot substitute. Membrane partitioning exhibits a steep dependence on anionic lipid abundance, which is mediated by electrostatic interactions between negatively charged lipids and basic residues within the distal C-terminal domain of PLC{beta}. We further demonstrate that anionic lipids cooperate with G{beta}{gamma} to regulate PLC{beta} membrane recruitment, such that the magnitude of G{beta}{gamma}-dependent recruitment is dictated by membrane anionic lipid content. These findings reconcile previous discrepancies regarding G{beta}{gamma}-mediated PLC{beta} membrane recruitment and establish membrane electrostatics as a key regulatory input that integrates lipid composition with G protein signaling to regulate PLC{beta} activity. SummaryMembrane association is a crucial component of PLC{beta} function and regulation, yet the mechanisms governing this process are poorly understood. The authors demonstrate that anionic lipids drive PLC{beta} membrane recruitment and influence G{beta}{gamma}-dependent activation, revealing how membrane composition shapes cellular signal transduction.

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Crawford, M. A., Bennett, M. B., Qin, Y., Cano, K. E., Gonzalez, T. G., Mojidra, R., Falzone, M. E.. 2026-07-21. Anionic lipids regulate PLCβ membrane recruitment. https://doi.org/10.64898/2026.07.20.739664

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