Fig. 3: Comparison of HCA2-Gi complex with CB1-Gi complex in Gi protein binding.
From: Structural insights into the human niacin receptor HCA2-Gi signalling complex
a Relative position of Gαi from HCA2-Gi complex (orange) and CB1-Gi complex (blue), aligned on receptor. The zoomed in view of Gi and receptor interface is shown on the right. b, c The binding interface of HCA2 (light purple) with Gαi (orange) and interacting residues from α5 helix of Gαi and adjacent ICL and helices of HCA2. d, e The binding interface of CB1 (green) with Gαi (blue), in similar views of (b) and (c). e, f, g cAMP inhibition assay of HCA2 interface mutation by MK-6892. h, i BRET validation of Gαi1 interface mutation by MK-6892 and niacin, respectively.
