Fig. 2. Arf1 mediates AP-1 dimerization.

(A) Subnanometer resolution map and associated atomic model fit of the Arf1^β1: β1 juxtaposed AP-1 dimer as viewed looking onto the tube surface. Atomic models are colored as denoted in (C). (B) Subnanometer resolution map and associated atomic model fit of the Arf1^γ:γ-juxtaposed AP-1 dimer as viewed looking onto the tube surface. Atomic models are colored as denoted in (C). (C) Cartoon representation of the asymmetric unit (AP-1₁:Arf1₂:Nef₁; red outline) flanked on either side by asymmetric units creating Arf1^γ:γ and Arf1^β1:β1 dimeric connections. (D) Zoom of the interface mediating Arf1^γ: γ and γ:γ dimeric interactions. (E) Zoom of the interface mediating Arf1^β1:β1 dimeric interactions. (F) Sequence alignment of μ and γ (or equivalent) domains from human and yeast APs. Yellow-highlighted residues are labeled according to their position in human AP-1 and correlate with residues shown in (D) and (E).