Structure of the GPVI CBD. (A) Ribbon diagram of GPVI. The N-terminal domain is labeled D1, and the C-terminal domain is D2. The predicted N-glycosylation site at N72 is shown by a gold ball. (B) Simulated annealing electron density omit map showing the C′E region of the CBD that differs from related immune receptors, with a ball-and-stick model of the deleted region superimposed. (C) Superposition of GPVI (blue), p58 KIR⁴⁰  (green), and FcαRI⁴¹  (yellow). The orientation is similar to that shown in panel A. (D) Superposition of D1 of GPVI (blue) and p58 KIR⁴⁰  (green) shown in 2 orientations, highlighting the unusual C′E region in GPVI (blue arrows). (E) Superposition of D2 of GPVI (blue) and p58 KIR⁴⁰  (green) in 2 orientations, highlighting the lack of an A′ strand and the extended CC′ hairpin in GPVI (note blue/green arrows).