Structural basis for the activation of PLC-γ isozymes by phosphorylation and cancer-associated mutations
- University of North Carolina at Chapel Hill, United States
Abstract
Direct activation of the human phospholipase C-g isozymes (PLC-g1, -g2) by tyrosine phosphorylation is fundamental to the control of diverse biological processes, including chemotaxis, platelet aggregation, and adaptive immunity. In turn, aberrant activation of PLC-g1 and PLC-g2 is implicated in inflammation, autoimmunity, and cancer. Although structures of isolated domains from PLC-g isozymes are available, these structures are insufficient to define how release of basal autoinhibition is coupled to phosphorylation-dependent enzyme activation. Here we describe the first high-resolution structure of a full-length PLC-g isozyme and use it to underpin a detailed model of their membrane-dependent regulation. Notably, an interlinked set of regulatory domains integrates basal autoinhibition, tyrosine kinase engagement, and additional scaffolding functions with the phosphorylation-dependent, allosteric control of phospholipase activation. The model also explains why mutant forms of the PLC-g isozymes found in several cancers have a wide spectrum of activities, and highlights how these activities are tuned during disease.
Data availability
Coordinates and structure factors for PLC-gamma1 are deposited in the Protein Data Bank under accession number 6PBC.
Article and author information
Author details
Funding
National Institutes of Health (R01-GM057391)
- John Sondek
National Institutes of Health (R01-GM098894)
- Qisheng Zhang
- John Sondek
National Science Foundation (DGE-1650116)
- Edhriz Siraliev-Perez
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2019, Hajicek et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Structural basis for the activation of PLC-γ isozymes by phosphorylation and cancer-associated mutations
eLife 8:e51700.
https://doi.org/10.7554/eLife.51700
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