FIGURE 2.

Structure of the yeast V-ATPase holoenzyme. (A) Cryo-electron micrograph structure of the assembled yeast V₁-V_o complex (Zhao et al., 2015). A combination of the electron density and a chain trace of the different subunits is used to demonstrate the structural features of the V-ATPase holoenzyme. The subunits and distinct domains are indicated. The three distinct EG heterodimers (green and purple) are indicated by numbers on the side of the respective heterodimers. Upper-case letters indicate the subunit of the V₁ sector and lower-cases represent the V_o-sector subunits. (B) A cartoon of the V-ATPase holoenzyme together with the functions performed by the V₁ and the V_o sectors is demonstrated. Precisely, the V₁ sector performs the ATP hydrolysis which is coupled to the proton transport function of the V_o sector. The direction of rotation of the rotor subunits (c8c′c″dDF) is indicated by a circular arrow on the hetero-decameric c-ring (cc′c″).