Abstract
Phospholipase C (PLC) enzymes convert phosphatidylinositol-4,5-bisphosphate (PIP2) into the second messengers diacylglyercol (DAG) and inositol-1,4,5-triphosphate (IP3). The production of these molecules promotes the release of intracellular calcium and activation of PKC, which results in profound cellular changes. The PLCβ subfamily is of particular interest given its prominent role in cardiovascular and neuronal signaling and its regulation by G protein-coupled receptors, as PLCβ is the canonical downstream target of the heterotrimeric G protein Gαq. However, this is not the only mechanism regulating PLCβ activity. Extensive structural and biochemical evidence has revealed regulatory roles for autoinhibitory elements within PLCβ, Gβγ, small molecular weight G proteins, and the lipid membrane itself. Such complex regulation highlights the central role this enzyme plays in cell signaling. A better understanding of the molecular mechanisms underlying the control of its activity will greatly facilitate the search for selective small molecule modulators of PLCβ.
- Gq/11 family
- Phospholipase C's
- IP3/DAG
- G protein regulation
- G[beta][gamma] signaling
- GAPs
- Cdc42, rho, rac, other small G proteins
- X-ray crystallography
- The American Society for Pharmacology and Experimental Therapeutics