8EAT

Yeast VO missing subunits a, e, and f in complex with Vma12-22p

Summary for 8EAT

• Entry DOI: 10.2210/pdb8eat/pdb
• EMDB information: 27985
• Descriptor: Vacuolar ATPase assembly protein VMA22, Vacuolar ATPase assembly integral membrane protein VPH2, V-type proton ATPase subunit F, ... (8 entities in total)
• Functional Keywords: v-type proton atpase, membrane protein
• Biological source: Saccharomyces cerevisiae (baker's yeast); More
• Total number of polymer chains: 15
• Total formula weight: 299943.91

Authors

Wang, H.,Bueler, S.A.,Rubinstein, J.L. (deposition date: 2022-08-29, release date: 2022-11-02, Last modification date: 2025-05-14)

Primary citation

Wang, H.,Bueler, S.A.,Rubinstein, J.L.
Structural basis of V-ATPase V O region assembly by Vma12p, 21p, and 22p.
Proc.Natl.Acad.Sci.USA, 120:e2217181120-e2217181120, 2023

PubMed Abstract: Vacuolar-type adenosine triphosphatases (V-ATPases) are rotary proton pumps that acidify specific intracellular compartments in almost all eukaryotic cells. These multi-subunit enzymes consist of a soluble catalytic V region and a membrane-embedded proton-translocating V region. V is assembled in the endoplasmic reticulum (ER) membrane, and V is assembled in the cytosol. However, V binds V only after V is transported to the Golgi membrane, thereby preventing acidification of the ER. We isolated V complexes and subcomplexes from bound to V-ATPase assembly factors Vma12p, Vma21p, and Vma22p. Electron cryomicroscopy shows how the Vma12-22p complex recruits subunits a, e, and f to the rotor ring of V while blocking premature binding of V. Vma21p, which contains an ER-retrieval motif, binds the V:Vma12-22p complex, "mature" V, and a complex that appears to contain a ring of loosely packed rotor subunits and the proteins YAR027W and YAR028W. The structures suggest that Vma21p binds assembly intermediates that contain a rotor ring and that activation of proton pumping following assembly of V with V removes Vma21p, allowing V-ATPase to remain in the Golgi. Together, these structures show how Vma12-22p and Vma21p function in V-ATPase assembly and quality control, ensuring the enzyme acidifies only its intended cellular targets.

PubMed: 36724250
DOI: 10.1073/pnas.2217181120

Experimental method

ELECTRON MICROSCOPY (3.1 Å)