Function of human Rh based on structure of RhCG at 2.1 Å

Franz Gruswitz(University of California, San Francisco), Sarika Chaudhary(University of California, San Francisco), Joseph D. Ho(University of California, San Francisco), Avner Schlessinger(QB3), Bobak Pezeshki(University of California, San Francisco), Chi-Min Ho(University of California, San Francisco), Andrej Šali(QB3), Connie M. Westhoff(American Red Cross), Robert M. Stroud(University of California, San Francisco)
Proceedings of the National Academy of Sciences
May 8, 2010
Cited by 199Open Access
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Abstract

In humans, NH(3) transport across cell membranes is facilitated by the Rh (rhesus) family of proteins. Human Rh C glycoprotein (RhCG) forms a trimeric complex that plays an essential role in ammonia excretion and renal pH regulation. The X-ray crystallographic structure of human RhCG, determined at 2.1 A resolution, reveals the mechanism of ammonia transport. Each monomer contains 12 transmembrane helices, one more than in the bacterial homologs. Reconstituted into proteoliposomes, RhCG conducts NH(3) to raise internal pH. Models of the erythrocyte Rh complex based on our RhCG structure suggest that the erythrocytic Rh complex is composed of stochastically assembled heterotrimers of RhAG, RhD, and RhCE.


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