Subunit interactions and requirements for inhibition of the yeast V1-ATPase.

ABSTRACT: Disassembly of the yeast V-ATPase into cytosolic V(1) and membrane V(0) sectors inactivates MgATPase activity of the V(1)-ATPase. This inactivation requires the V(1) H subunit (Parra, K. J., Keenan, K. L., and Kane, P. M. (2000) J. Biol. Chem. 275, 21761-21767), but its mechanism is not fully understood. The H subunit has two domains. Interactions of each domain with V(1) and V(0) subunits were identified by two-hybrid assay. The B subunit of the V(1) catalytic headgroup interacted with the H subunit N-terminal domain (H-NT), and the C-terminal domain (H-CT) interacted with V(1) subunits B, E (peripheral stalk), and D (central stalk), and the cytosolic N-terminal domain of V(0) subunit Vph1p. V(1)-ATPase complexes from yeast expressing H-NT are partially inhibited, exhibiting 26% the MgATP

SUBMITTER: Diab H 

PROVIDER: S-EPMC2679431 | biostudies-literature | 2009 May

REPOSITORIES: biostudies-literature