FIGURE 3.

Structure of GNAQ. Protein map of GNAQ. GNAQ has 3 switch regions (SW): switch regions I and II are part of the GTP binding cleft and have a RAS-like domain for GTP hydrolysis; all three switch regions have key sites for extrinsic regulation by G protein signaling modulators. The p.R183Q and p.Q209L activating mutations are present in switch regions I and II, respectively. GNAQ has a binding domain (BD) for PLC effector function, a binding domain that interacts with the Gβγ subunit during the “off” state, and a GPCR binding domain. Image created using BioRender. Crystal structure (PDB ID: 4GNK) with GDP (red) docked in binding cleft and p.R183Q and p.Q209L mutations (cyan). P loop region with Walker A motif shown in yellow. Switch (SW) I, II, and III shown in pink. Supplementary Video available online. Molecular graphics performed with UCSF ChimeraX, developed by the Resource for Biocomputing, Visualization, and Informatics at the University of California, San Francisco, with support from National Institutes of Health R01-GM129325 and the Office of Cyber Infrastructure and Computational Biology, National Institute of Allergy and Infectious Diseases.