7rd7

Publication Abstract from PubMed

P4 ATPases are lipid flippases that are phylogenetically grouped into P4A, P4B and P4C clades. The P4A ATPases are heterodimers composed of a catalytic alpha-subunit and accessory beta-subunit, and the structures of several heterodimeric flippases have been reported. The S. cerevisiae Neo1 and its orthologs represent the P4B ATPases, which function as monomeric flippases without a beta-subunit. It has been unclear whether monomeric flippases retain the architecture and transport mechanism of the dimeric flippases. Here we report the structure of a P4B ATPase, Neo1, in its E1-ATP, E2P-transition, and E2P states. The structure reveals a conserved architecture as well as highly similar functional intermediate states relative to dimeric flippases. Consistently, structure-guided mutagenesis of residues in the proposed substrate translocation path disrupted Neo1's ability to establish membrane asymmetry. These observations indicate that evolutionarily distant P4 ATPases use a structurally conserved mechanism for substrate transport.

Structural basis of the P4B ATPase lipid flippase activity.,Bai L, Jain BK, You Q, Duan HD, Takar M, Graham TR, Li H Nat Commun. 2021 Oct 13;12(1):5963. doi: 10.1038/s41467-021-26273-0. PMID:34645814^[2]

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