4efa

Publication Abstract from PubMed

Vacuolar ATPases (V-ATPases) are multisubunit rotary motor proton pumps that function to acidify subcellular organelles in all eukaryotic organisms. V-ATPase is regulated by a unique mechanism that involves reversible dissociation into V(1)-ATPase and V(o) proton channel, a process that involves breaking of protein interactions mediated by subunit C, the cytoplasmic domain of subunit "a" and three "peripheral stalks," each made of a heterodimer of E and G subunits. Here, we present crystal structures of a yeast V-ATPase heterotrimeric complex composed of EG heterodimer and the head domain of subunit C (C(head)). The structures show EG heterodimer folded in a noncanonical coiled coil that is stabilized at its N-terminal ends by binding to C(head). The coiled coil is disrupted by a bulge of partially unfolded secondary structure in subunit G and we speculate that this unique feature in the eukaryotic V-ATPase peripheral stalk may play an important role in enzyme structure and regulation by reversible dissociation.

Crystal Structure of the Yeast Vacuolar ATPase Heterotrimeric EGC(head) Peripheral Stalk Complex.,Oot RA, Huang LS, Berry EA, Wilkens S Structure. 2012 Sep 18. pii: S0969-2126(12)00321-8. doi:, 10.1016/j.str.2012.08.020. PMID:23000382^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.