Crystal Structure of Human Aquaporin 4 at 1.8 and its Mechanism of Conductance

Experimental Data Snapshot

  • Resolution: 1.80 Å
  • R-Value Free: 0.165 
  • R-Value Work: 0.160 
  • R-Value Observed: 0.160 

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Crystal structure of human aquaporin 4 at 1.8 A and its mechanism of conductance.

Ho, J.D.Yeh, R.Sandstrom, A.Chorny, I.Harries, W.E.Robbins, R.A.Miercke, L.J.Stroud, R.M.

(2009) Proc Natl Acad Sci U S A 106: 7437-7442

  • DOI: https://doi.org/10.1073/pnas.0902725106
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 

    Aquaporin (AQP) 4 is the predominant water channel in the mammalian brain, abundantly expressed in the blood-brain and brain-cerebrospinal fluid interfaces of glial cells. Its function in cerebral water balance has implications in neuropathological disorders, including brain edema, stroke, and head injuries. The 1.8-A crystal structure reveals the molecular basis for the water selectivity of the channel. Unlike the case in the structures of water-selective AQPs AqpZ and AQP1, the asparagines of the 2 Asn-Pro-Ala motifs do not hydrogen bond to the same water molecule; instead, they bond to 2 different water molecules in the center of the channel. Molecular dynamics simulations were performed to ask how this observation bears on the proposed mechanisms for how AQPs remain totally insulating to any proton conductance while maintaining a single file of hydrogen bonded water molecules throughout the channel.

  • Organizational Affiliation

    Graduate Program in Chemistry and Chemical Biology and Department of Biochemistry and Biophysics, Genentech Hall, University of California, 600 16th Street, San Francisco, CA 94158-2517, USA.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Aquaporin-4223Homo sapiensMutation(s): 0 
Gene Names: AQP4
Membrane Entity: Yes 
UniProt & NIH Common Fund Data Resources
Find proteins for P55087 (Homo sapiens)
Explore P55087 
Go to UniProtKB:  P55087
PHAROS:  P55087
GTEx:  ENSG00000171885 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP55087
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Resolution: 1.80 Å
  • R-Value Free: 0.165 
  • R-Value Work: 0.160 
  • R-Value Observed: 0.160 
  • Space Group: P 4 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 82.058α = 90
b = 82.058β = 90
c = 76.353γ = 90
Software Package:
Software NamePurpose
Blu-Icedata collection
HKL-2000data reduction
HKL-2000data scaling

Structure Validation

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Ligand Structure Quality Assessment 

Entry History 

Revision History  (Full details and data files)

  • Version 1.0: 2009-03-31
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Advisory, Version format compliance
  • Version 1.2: 2020-07-29
    Type: Remediation
    Reason: Carbohydrate remediation
    Changes: Data collection, Derived calculations, Structure summary
  • Version 1.3: 2024-02-21
    Changes: Data collection, Database references, Structure summary