| First Author | Fenton RA | Year | 2000 |
| Journal | Am J Physiol Cell Physiol | Volume | 279 |
| Issue | 5 | Pages | C1425-31 |
| PubMed ID | 11029290 | Mgi Jnum | J:68327 |
| Mgi Id | MGI:1932566 | Doi | 10.1152/ajpcell.2000.279.5.C1425 |
| Citation | Fenton RA, et al. (2000) Molecular characterization of a novel UT-A urea transporter isoform (UT-A5) in testis. Am J Physiol Cell Physiol 279(5):C1425-31 |
| abstractText | Urea movement across plasma membranes is modulated by specialized transporter proteins that are products of two genes, termed UT-A and UT-B. These proteins play key roles in the urinary concentrating mechanism and fluid homeostasis. We have isolated and characterized a 1.4-kb cDNA from testes encoding a new isoform (UT-A5) belonging to the UT-A transporter family. For comparison, we also isolated a 2. 0-kb cDNA from mouse kidney inner medulla encoding the mouse UT-A3 homologue. The UT-A5 cDNA has a putative open reading frame encoding a 323-amino acid protein, making UT-A5 the smallest UT-A family member in terms of molecular size. Its putative topology is of particular interest, because it calls into question earlier models of UT-A transporter structure. Expression of UT-A5 cRNA in Xenopus oocytes mediates phloretin-inhibitable urea uptake and does not translocate water. The distribution of UT-A5 mRNA is restricted to the peritubular myoid cells forming the outermost layer of the seminiferous tubules within the testes and is not detected in kidney. UT-A5 mRNA levels are coordinated with the stage of testes development and increase 15 days postpartum, commensurate with the start of seminiferous tubule fluid movement. |
