Related Experiment Video
Updated: May 9, 2026

Manipulation and Analysis of Cell Cycle-Dependent Processes in Budding Yeast
Published on: September 26, 2025
Structural basis of Vps33A recruitment to the human HOPS complex by Vps16
Stephen C Graham1, Lena Wartosch, Sally R Gray
1Department of Clinical Biochemistry, Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, United Kingdom. scg34@cam.ac.uk
Abstract:
The multisubunit homotypic fusion and vacuole protein sorting (HOPS) membrane-tethering complex is required for late endosome-lysosome and autophagosome-lysosome fusion in mammals. We have determined the crystal structure of the human HOPS subunit Vps33A, confirming its identity as a Sec1/Munc18 family member. We show that HOPS subunit Vps16 recruits Vps33A to the human HOPS complex and that residues 642-736 are necessary and sufficient for this interaction, and we present the crystal structure of Vps33A in complex with Vps16(642-736). Mutations at the binding interface disrupt the Vps33A-Vps16 interaction both in vitro and in cells, preventing recruitment of Vps33A to the HOPS complex. The Vps33A-Vps16 complex provides a structural framework for studying the association between Sec1/Munc18 proteins and tethering complexes.
Related Concept Videos
Protein Complex Assembly
Many viruses self-assemble into a fully functional unit using the infected host cell to...
Protein Complex Assembly
Many viruses self-assemble into a fully functional unit using the infected host cell to...
Coat Assembly and GTPases
Coat assembly depends on the local availability of phosphatidylinositol phosphates or PIPs and GTP-binding proteins. Adaptor proteins, which link the coat proteins to the membrane, bind to these PIPs and play a crucial role in controlling...
Intralumenal Vesicles and Multivesicular Bodies
Cotranslational Protein Translocation
Sec61 channel partners for cotranslational translocation
During cotranslational translocation, the Sec61 channel partners with the signal recognition particle (SRP), the signal recognition particle receptor (SR), and the ribosomes to transport the nascent polypeptide chain...
Microtubule Associated Proteins (MAPs)

