Related Experiment Video
Updated: Aug 19, 2026

Single-molecule Super-resolution Imaging of Phosphatidylinositol 4,5-bisphosphate in the Plasma Membrane with Novel Fluorescent Probes
Published on: October 15, 2016
G-protein-activated phospholipase C-beta, new partners for cell polarity proteins Par3 and Par6
Yi Cai1, Lewis J Stafford, Brad A Bryan
1Department of Medical Biochemistry and Genetics, Alkek Institute of Biosciences and Technology, Texas A&M University System Health Science Center, 2121 W Holcombe Blvd, Houston, TX 77030, USA.
Abstract:
Cell polarity and asymmetric cell division are fundamental traits of all living cells and play an essential role in embryonic development, neuronal cell chirality formation, and maintenance of mammalian epithelial cell morphology. Heterotrimeric GTP-binding proteins (G proteins) are involved in directing cell polarity and asymmetric cell division in different organisms. However, the mechanism for G-protein-mediated cell polarity and asymmetric cell division is poorly understood. In this study, we have demonstrated that G-protein-activated phospholipase C-beta (PLC-beta) interacts with cell polarity proteins Par3 and Par6 (Par: partition-defective) to form protein complexes and to mediate downstream signal transduction. The interactions between PLC-beta and Par proteins are direct and require the extreme C-terminal-specific sequence motifs of PLC-beta and the PDZ (PSD95/Dlg/ZO-1) domains of Par proteins. Binding of Par proteins with PLC-beta stimulates PLC-beta enzymatic activity, leading to the hydrolysis of phosphatidylinositol-4,5-bisphosphate, and the production of diacylglycerol and inositol 1,4,5-triphosphate, important mediators in cell polarity and cell asymmetric division processes. Furthermore, we have shown that coexpression of PLC-beta with Par proteins induces transcriptional activation coupled to intracellular Ca2+ and the Wnt signaling pathway. Therefore, our data suggest that the interaction of PLC-beta with cell polarity Par proteins may serve as a nexus to transduce extracellular signals to transcriptional regulation through G-protein-mediated signaling pathway in cell polarity and cell asymmetric division.
More Related Videos
09:40Imaging G-protein Coupled Receptor (GPCR)-mediated Signaling Events that Control Chemotaxis of Dictyostelium Discoideum
Published on: September 20, 2011
08:49Fluorescence-Based Measurements of Phosphatidylserine/Phosphatidylinositol 4-Phosphate Exchange Between Membranes
Published on: March 14, 2021
Related Concept Videos
Cell Polarization by Rho Proteins
IP3/DAG Signaling Pathway
Mechanism of Filopodia Formation
Their main function is to guide migrating cells during normal tissue morphogenesis or cancer metastasis by recognizing and making initial contacts with the extracellular matrix. However, they can also act as stationary cell anchors or help to establish communication...
Phosphoinositides and PIPs
Different phosphoinositides are synthesized and recruited on the cytosolic face of the plasma membrane. The localization of specific phosphoinositides concentrated in separate membrane...
Mechanism of Lamellipodia Formation
Small GTPases - Ras and Rho
Three regulatory proteins control their activity: