Membrane topology of aquaporin CHIP. Analysis of functional epitope-scanning mutants by vectorial proteolysis.

@article{Preston1994MembraneTO,
  title={Membrane topology of aquaporin CHIP. Analysis of functional epitope-scanning mutants by vectorial proteolysis.},
  author={Gregory M. Preston and Jin Sup Jung and William B Guggino and Peter Agre},
  journal={The Journal of biological chemistry},
  year={1994},
  volume={269 3},
  pages={1668-73}
}
CHIP is the archetypal member of the aquaporins, a widely expressed family of membrane water channels. The NH2- and COOH-terminal halves of CHIP are sequence-related, and hydropathy analysis predicted six membrane-spanning domains with five connecting loops (A-E). Here, we determined the membrane topology of CHIP expressed in Xenopus oocytes using biologically active recombinant channels. CHIP is glycosylated at Asn-42, indicating loop A is exofacial. An epitope from the coronavirus E1… CONTINUE READING