UniProt functional annotation for Q5QF96

UniProt code: Q5QF96.

Organism:		Bos taurus (Bovine).
Taxonomy:		Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Laurasiatheria; Artiodactyla; Ruminantia; Pecora; Bovidae; Bovinae; Bos.
Function:		Urea channel that facilitates transmembrane urea transport down a concentration gradient. A constriction of the transmembrane channel functions as selectivity filter through which urea is expected to pass in dehydrated form. The rate of urea conduction is increased by hypotonic stress. Plays an important role in the kidney medulla collecting ducts, where it allows rapid equilibration between the lumen of the collecting ducts and the interstitium, and thereby prevents water loss driven by the high concentration of urea in the urine. Facilitates urea transport across erythrocyte membranes. May also play a role in transmembrane water transport, possibly by indirect means. {ECO:0000269|PubMed:15845882, ECO:0000269|PubMed:22733730}.
Subunit:		Identified in a complex with STOM (By similarity). Homotrimer; each subunit contains a pore through which urea permeates. {ECO:0000250, ECO:0000269|PubMed:22733730}.
Subcellular location:		Cell membrane; Multi-pass membrane protein. Basolateral cell membrane; Multi-pass membrane protein. Note=Restricted to the basolateral membrane in various portions of the urothelium.
Tissue specificity:		Isoform 1 and isoform 2 are expressed in kidney. Also expressed in the rumen (at protein level). Isoform 2 seems predominant in both tissues. {ECO:0000269|PubMed:15845882}.
Similarity:		Belongs to the urea transporter family. {ECO:0000305}.

Annotations taken from UniProtKB at the EBI.