Phospholipase Cgamma1 controls surface expression of TRPC3 through an intermolecular PH domain

Area of Science:

• Molecular Biology
• Cell Signaling
• Biochemistry

Background:

• Lipid regulation of ion channels is crucial, yet specific binding motifs are often unknown.
• Phospholipase Cgamma1 (PLC-gamma1) is known to interact with and regulate TRPC3 channels.
• This interaction involves a partial pleckstrin homology (PH) domain in PLC-gamma1.

Purpose of the Study:

• To identify the molecular basis of PLC-gamma1 and TRPC3 channel interaction.
• To investigate the role of PH and PH-like domains in this lipid-mediated regulation.
• To explore a novel signaling mechanism involving intermolecular PH-like domains.

Main Methods:

• Development of a gestalt algorithm to identify 'invisible' PH and PH-like domains.
• Biochemical assays to confirm interaction between PLC-gamma1 and TRPC3 domains.
• Analysis of cell-surface expression of TRPC3 channels.

Main Results:

• A partial PH domain in PLC-gamma1 interacts with a complementary partial PH-like domain in TRPC3.
• This interaction facilitates lipid binding to TRPC3 channels.
• The interaction promotes the cell-surface expression of TRPC3 channels.

Conclusions:

• Intermolecular interactions between partial PH and PH-like domains represent a novel signaling mode.
• PH-like domains are more abundant than previously recognized.
• This interaction mechanism is critical for TRPC3 channel function and calcium signaling.