3GD8

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

Summary for 3GD8

• Entry DOI: 10.2210/pdb3gd8/pdb
• Descriptor: Aquaporin-4, GLYCEROL, octyl beta-D-glucopyranoside, ... (4 entities in total)
• Functional Keywords: brain edema, aquaporin, proton exclusion, structural genomics, psi-2, protein structure initiative, center for structures of membrane proteins, csmp, glycoprotein, membrane, phosphoprotein, transmembrane, transport, membrane protein
• Biological source: Homo sapiens (Human)
• Total number of polymer chains: 1
• Total formula weight: 24279.58

Authors

Ho, J.D.,Yeh, R.,Sandstrom, A.,Chorny, I.,Harries, W.E.C.,Robbins, R.A.,Miercke, L.J.W.,Stroud, R.M.,Center for Structures of Membrane Proteins (CSMP) (deposition date: 2009-02-23, release date: 2009-03-31, Last modification date: 2024-02-21)

Primary citation

Ho, J.D.,Yeh, R.,Sandstrom, A.,Chorny, I.,Harries, W.E.,Robbins, R.A.,Miercke, L.J.,Stroud, R.M.
Crystal structure of human aquaporin 4 at 1.8 A and its mechanism of conductance.
Proc.Natl.Acad.Sci.USA, 106:7437-7442, 2009

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.

PubMed: 19383790
DOI: 10.1073/pnas.0902725106

Experimental method

X-RAY DIFFRACTION (1.8 Å)