Structure and permeation mechanism of a mammalian urea transporter.
Levin, E.J., Cao, Y., Enkavi, G., Quick, M., Pan, Y., Tajkhorshid, E., Zhou, M.(2012) Proc Natl Acad Sci U S A 109: 11194-11199
- PubMed: 22733730 
- DOI: 10.1073/pnas.1207362109
- Primary Citation of Related Structures:  
4EZC, 4EZD - PubMed Abstract: 
As an adaptation to infrequent access to water, terrestrial mammals produce urine that is hyperosmotic to plasma. To prevent osmotic diuresis by the large quantity of urea generated by protein catabolism, the kidney epithelia contain facilitative urea transporters (UTs) that allow rapid equilibration between the urinary space and the hyperosmotic interstitium ...