High-resolution x-ray structure of human aquaporin 5

Research output: Contribution to journalArticle

Abstract

Human aquaporin 5 (HsAQP5)facilitates the transport of water across plasma membranes and has been identified within cells of the stomach, duodenum, pancreas, airways, lungs, salivary glands, sweat glands, eyes, lacrimal glands, and the inner ear. AQP5, like AQP2, is subject to posttranslational regulation by phosphorylation, at which point it is trafficked between intracellular storage compartments and the plasma membrane. Details concerning the molecular mechanism of membrane trafficking are unknown. Here we report the x-ray structure of HsAQP5 to 2.0-angstrom resolution and highlight structural similarities and differences relative to other eukaryotic aquaporins. A lipid occludes the putative central pore, preventing the passage of gas or ions through the center of the tetramer. Multiple consensus phosphorylation sites are observed in the structure and their potential regulatory role is discussed. We postulate that a change in the conformation of the C terminus may arise from the phosphorylation of AQP5 and thereby signal trafficking.

Details

Authors
Organisations
External organisations
  • University of Gothenburg
  • Chalmers University of Technology
  • Max Planck Institute of Biophysics
  • University of Kalmar
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Biological Sciences

Keywords

  • heterologous overexpression, crystallography, water channel protein, trafficking, membrane protein
Original languageEnglish
Pages (from-to)13327-13332
JournalProceedings of the National Academy of Sciences
Volume105
Issue number36
Publication statusPublished - 2008
Publication categoryResearch
Peer-reviewedYes