8OP8

Cryo-EM structure of P5A-ATPase CtSpf1 (E2.Pi state with endogenous helix cargo bound)

Summary for 8OP8

• Entry DOI: 10.2210/pdb8op8/pdb
• Related: 8OP3 8OP4 8OP5 8OP6 8OP7
• EMDB information: 17039 17040 17041 17042 17043 17044
• Descriptor: Unknown helix, Cation-transporting ATPase-like protein, TETRAFLUOROALUMINATE ION, ... (5 entities in total)
• Functional Keywords: translocase, membrane protein
• Biological source: Saccharomyces cerevisiae; More
• Total number of polymer chains: 2
• Total formula weight: 151926.78

Authors

Li, P.,Gourdon, P. (deposition date: 2023-04-06, release date: 2024-10-16, Last modification date: 2024-11-20)

Primary citation

Li, P.,Bagenholm, V.,Hagglund, P.,Lindkvist-Petersson, K.,Wang, K.,Gourdon, P.
The structure and function of P5A-ATPases.
Nat Commun, 15:9605-9605, 2024

PubMed Abstract: Endoplasmic reticulum (ER) membrane resident P5A-ATPases broadly affect protein biogenesis and quality control, and yet their molecular function remains debated. Here, we report cryo-EM structures of a P5A-ATPase, CtSpf1, covering multiple transport intermediates of the E1 → E1-ATP → E1P-ADP → E1P → E2P → E2.P → E2 → E1 cycle. In the E2P and E2.P states a cleft spans the entire membrane, holding a polypeptide cargo molecule. The cargo includes an ER luminal extension, pinpointed as the C-terminus in the E2.P state, which reenters the membrane in E2P. The E1 structure harbors a cytosol-facing cavity that is blocked by an insertion we refer to as the Plug-domain. The Plug-domain is nestled to key ATPase features and is displaced in the E1P-ADP and E1P states. Collectively, our findings are compatible with a broad range of proteins as cargo, with the P5A-ATPases serving a role in membrane removal of helices, although insertion/secretion cannot be excluded, as well as with a mechanistic role of the Plug-domain.

PubMed: 39505844
DOI: 10.1038/s41467-024-53757-6

Experimental method

ELECTRON MICROSCOPY (3.48 Å)