Publication Abstract from PubMed
The vacuolar protein sorting (Vps) pathway, in which Vps4 class I AAA-ATPases play a central role, regulates growth factor receptors, immune response, and developmental signaling, and participates in tumor suppression, apoptosis, and retrovirus budding. We present the first atomic structure of the nucleotide-free yeast His(6)DeltaNVps4p dimer and its AMPPNP (5'-adenylyl-beta,gamma-imidodiphosphate)-bound tetradecamer, derived from a cryo electron microscopy map. Vps4p dimers form two distinct heptameric rings and accommodate AAA cassettes in a head-to-head--not in a head-to-tail-fashion as in class II AAA-ATPases. Our model suggests a mechanism for disassembling ESCRT (endosomal sorting complex required for transport) complexes by movements of substrate-binding domains located at the periphery of the tetradecamer during ATP hydrolysis in one ring, followed by translocation through the central pore and ATP hydrolysis in the second ring.
Vacuolar protein sorting: two different functional states of the AAA-ATPase Vps4p.,Hartmann C, Chami M, Zachariae U, de Groot BL, Engel A, Grutter MG J Mol Biol. 2008 Mar 21;377(2):352-63. Epub 2008 Jan 15. PMID:18272179[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
