Conformational cycle of human polyamine transporter ATP13A2

Nat Commun. 2023 Apr 8;14(1):1978. doi: 10.1038/s41467-023-37741-0.

Abstract

Dysregulation of polyamine homeostasis strongly associates with human diseases. ATP13A2, which is mutated in juvenile-onset Parkinson's disease and autosomal recessive spastic paraplegia 78, is a transporter with a critical role in balancing the polyamine concentration between the lysosome and the cytosol. Here, to better understand human ATP13A2-mediated polyamine transport, we use single-particle cryo-electron microscopy to solve high-resolution structures of human ATP13A2 in six intermediate states, including the putative E2 structure for the P5 subfamily of the P-type ATPases. These structures comprise a nearly complete conformational cycle spanning the polyamine transport process and capture multiple substrate binding sites distributed along the transmembrane regions, suggesting a potential polyamine transport pathway. Integration of high-resolution structures, biochemical assays, and molecular dynamics simulations allows us to obtain a better understanding of the structural basis of how hATP13A2 transports polyamines, providing a mechanistic framework for ATP13A2-related diseases.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cryoelectron Microscopy
  • Humans
  • Membrane Transport Proteins
  • Parkinsonian Disorders* / metabolism
  • Polyamines*
  • Proton-Translocating ATPases / metabolism

Substances

  • Polyamines
  • Proton-Translocating ATPases
  • Membrane Transport Proteins
  • ATP13A2 protein, human