Stable association between G alpha(q) and phospholipase C beta 1 in living cells
- PMID: 16754659
- DOI: 10.1074/jbc.M512330200
Stable association between G alpha(q) and phospholipase C beta 1 in living cells
Abstract
Signal transduction through G alpha(q) involves stimulation of phospholipase C beta (PLC beta) that results in increased intracellular Ca2+ and activation of protein kinase C. We have measured complex formation between G alpha(q) and PLC beta1 in vitro and in living PC12 and HEK293 cells by fluorescence resonance energy transfer. In vitro measurements show that PLC beta1 will bind to G alpha(q)(guanosine 5'-3-O-(thio)triphosphate) and also to G alpha(q)(GDP), and the latter association has a different protein-protein orientation. In cells, image analysis of fluorescent-tagged proteins shows that G alpha(q) is localized almost entirely to the plasma membrane, whereas PLC beta1 has a significant cytosolic population. By using fluorescence resonance energy transfer, we found that these proteins are pre-associated in the unstimulated state in PC12 and HEK293 cells. By determining the cellular levels of the two proteins in transfected versus nontransfected cells, we found that under our conditions overexpression should not significantly promote complex formation. G alpha(q)-PLC beta1 complexes are observed in both single cell measurements and measurements of a large (i.e. 10(6)) cell suspension. The high level (approximately 40% maximum) of FRET is surprising considering that G alpha(q) is more highly expressed than PLC beta1 and that not all PLC beta1 is plasma membrane-localized. Our measurements suggest a model in which G proteins and effectors can exist in stable complexes prior to activation and that activation is achieved through changes in intermolecular interactions rather than diffusion and association. These pre-formed complexes in turn give rise to rapid, localized signals.
Similar articles
-
Small cell lung carcinoma exhibits greater phospholipase C-beta1 expression and edelfosine resistance compared with non-small cell lung carcinoma.Cancer Res. 2000 May 15;60(10):2730-6. Cancer Res. 2000. PMID: 10825148
-
Activation of phospholipase C by the alpha subunits of the Gq and G11 proteins in transfected Cos-7 cells.J Biol Chem. 1992 Jan 25;267(3):1811-7. J Biol Chem. 1992. PMID: 1309799
-
The use of green fluorescent proteins to view association between phospholipase C beta and G protein subunits in cells.Methods Mol Biol. 2004;237:223-32. doi: 10.1385/1-59259-430-1:223. Methods Mol Biol. 2004. PMID: 14501053 Review.
-
Membrane signaling and progesterone in female and male osteoblasts. II. Direct involvement of G alpha q/11 coupled to PLC-beta 1 and PLC-beta 3.J Cell Biochem. 2000 Aug 2;79(2):173-81. doi: 10.1002/1097-4644(20001101)79:2<173::aid-jcb10>3.0.co;2-3. J Cell Biochem. 2000. PMID: 10967545
-
Assay for G protein-dependent activation of phospholipase C beta using purified protein components.Methods Mol Biol. 2004;237:67-75. doi: 10.1385/1-59259-430-1:67. Methods Mol Biol. 2004. PMID: 14501039 Review.
Cited by
-
PLCβ1 by-passes early growth response -1 to induce the differentiation of neuronal cells.Cell Death Discov. 2024 May 24;10(1):250. doi: 10.1038/s41420-024-02009-z. Cell Death Discov. 2024. PMID: 38789419 Free PMC article.
-
Interleukin 31 receptor α promotes smooth muscle cell contraction and airway hyperresponsiveness in asthma.Nat Commun. 2023 Dec 11;14(1):8207. doi: 10.1038/s41467-023-44040-1. Nat Commun. 2023. PMID: 38081868 Free PMC article.
-
GNA12 regulates C5a-induced migration by downregulating C5aR1-PLCβ2-PI3K-AKT-ERK1/2 signaling.Biophys Rep. 2023 Feb 28;9(1):33-44. doi: 10.52601/bpr.2023.230001. Biophys Rep. 2023. PMID: 37426201 Free PMC article.
-
Hemostatic Effect of 20(S)-Panaxadiol by Induced Platelet Aggregation Depending on Calcium Signaling Pathway.Biomed Res Int. 2022 Sep 20;2022:8265898. doi: 10.1155/2022/8265898. eCollection 2022. Biomed Res Int. 2022. PMID: 36177062 Free PMC article.
-
A compendium of validated pain genes.WIREs Mech Dis. 2022 Nov;14(6):e1570. doi: 10.1002/wsbm.1570. Epub 2022 Jun 27. WIREs Mech Dis. 2022. PMID: 35760453 Free PMC article. Review.
Publication types
MeSH terms
Substances
Grants and funding
LinkOut - more resources
Full Text Sources
Molecular Biology Databases
Miscellaneous