Official Project Description
AtGPA1 is Arabidopsis thaliana's alpha subunit of the G-protein signaling complex, responsible for signaling cell proliferation, regulating environmental responses, and sensing sugar availability.
Being a self-activating G-protein that likely doesn't require a GPCR, its signaling mechanism is unique compared to metazoan G-protein signaling cascades, and as such is an unexplored domain in the larger G-protein signaling landscape. Post-translational modifications (PTMs) are covalent modifications to proteins that include phosphorylation, glycosylation, oxidation, nitrosylation, and even full protein additions such as ubiquitination and SUMOylation.
These PTMs may be important to the GTP hydrolysis activity of AtGPA1, but may also be important in stabilizing the complex between AtGPA1 and its partner proteins, including the the rest of the G-protein subunits (AtAGB1 & AtAGG1) and the Regulator of G-protein Signaling (AtRGS).
Performing atomistic simulations with various mutations that abolish the various PTMs present in AtGPA1 complexes will allow us to further our understanding of the role of these PTMs in its conformational dynamics and complex stability.