
Computational and Structural Biotechnology Journal, Journal Year: 2025, Volume and Issue: unknown
Published: April 1, 2025
Protein phosphorylation regulates G protein signaling in plants. AtRGS1 primarily modulates AtGPA1, the canonical Gα subunit heterotrimeric complex. possesses both a seven-transmembrane (7TM) domain connected to cytoplasmic Regulator of Signaling (RGS box domain) by flexible linker region. This study presents novel function highly conserved, known site, Ser278, within this region utilizing molecular dynamics (MD) simulations with vivo experimental validation. We show that at Ser278 is crucial for establishing specific interactions stabilizing positioning and orientation RGS membrane. Phosphorylation enhances formation stable hydrogen bonds between phosphorylated conserved residues domain, influencing flexibility mobility thus modulating its interface AtGPA1. Consistent MD simulations, assays demonstrated reduced binding AtGPA1 conferred changes physiology. Specifically, non-phosphorylation mutation decreased plant immune responses endocytosis evoked bacterial effector, flg22. sequence analysis diverse 7TM-RGS proteins suggest conservation mechanism across land plants, emphasizing critical role previously overlooked
Language: Английский