Cloning and functional expression of a urea transporter from human bone marrow cells.

摘要: A rapid passive urea transport has been previously described in the mammalian renal inner medullary collecting duct epithelial cells and erythrocytes. Recently, a vasopressin-regulated transporter (UT2) cloned from rabbit kidney cDNA library (You, G., Smith, C. P., Kanai, Y., Lee, W. S., Stelzner, M., Hediger, M. A. (1993) Nature 365, 844-847). We now report cloning characterization of complementary DNA (HUT11) encoding an isolated human bone marrow library. It encodes 43,000-Da polypeptide 391 amino acids that exhibited 63% sequence identity with similar membrane topology. HUT11 carries 2 putative glycosylation sites 10 cysteines, which only 7 are conserved at equivalent position UT2. transcripts have identified erythroid tissues. Expression studies Xenopus oocytes demonstrated mediates facilitated was inhibited, as erythrocytes, by very low concentrations phloretin, p-chloromercuribenzene sulfonate, analogues. No unidirectional movements charged molecules, glycerol, or water were associated expression oocytes. These findings suggest is most likely responsible for red blood cells.