Fig. 6: Mechanism of OR52cs activation by OCA binding.
From: Understanding the molecular mechanisms of odorant binding and activation of the human OR52 family
Schematic representation of the activation mechanism of OR52cs upon OCA binding. In the apo state (left, light yellow), there is a wide opening between TM5 and TM6, possibly acting as an entrance for OCA. The highly conserved R6.59 on the extracellular end of TM6 is flexible, represented as multiple conformations. Inward and outward movements of the extracellular and intracellular regions of TM6 and TM6 rotation upon OCA binding are indicated by red arrows. In the active state (green), OCA-mediated interactions in the odorant-binding pocket (middle), and distinct interaction networks that stabilize the active conformation (right) are presented. The active conformation is further stabilized by interactions between OR52cs and G protein (cyan). OCA molecules are shown in the ball-and-stick model. Figure was generated using ChimeraX and Powerpoint.
