The structure of aquaporin-1 at 4.5-A resolution reveals short alpha-helices in the center of the monomer.

@article{Mitsuoka1999TheSO,
  title={The structure of aquaporin-1 at 4.5-A resolution reveals short alpha-helices in the center of the monomer.},
  author={Kaoru Mitsuoka and Kazuyoshi Murata and Thomas Walz and Teruhisa Hirai and Peter Agre and J. Bernard Heymann and Andreas Engel and Yoshinori Fujiyoshi},
  journal={Journal of structural biology},
  year={1999},
  volume={128 1},
  pages={
          34-43
        }
}
Aquaporin-1 is a water channel found in mammalian red blood cells that is responsible for high water permeability of its membrane. Our electron crystallographic analysis of the three-dimensional structure of aquaporin-1 at 4.5-A resolution confirms the previous finding that each subunit consists of a right-handed bundle of six highly tilted transmembrane helices that surround a central X-shaped structure. In our new potential map, the rod-like densities for the transmembrane helices show… 

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