High impact information on Slc6a20

• It also shows that the structurally highly similar orphan transporters XT2 and XT3 have the same luminal but a slightly differing axial localization along the kidney proximal tubule [1].
• We show here by immunofluorescence that all four mouse B degrees AT-cluster transporters localize, with differential axial gradients, to the brush-border membrane of proximal kidney tubule and, with the possible exception of XT3, also of intestine [1].
• Screening experiments to identify the substrate(s) of these proteins failed to identify specific uptake with any of the tested compounds; however, immunofluorescent microscopy demonstrated that epitope-tagged variants of the protein products of the XT2 and XT3 cDNAs were present on the plasma membrane of transfected cells [2].
• Expression of the second gene (XT3) was found to be conserved in human kidney, and partial sequence was obtained from a human cDNA library [2].
• The expressions of both XT2 and XT3 RNAs were determined in mouse and human tissues, respectively, and the locations of the two genes within the mouse genome were identified [2].

Anatomical context of Slc6a20

• Expression of XT3s1 was found in brain, kidney, small intestine, thymus, spleen and lung, whereas XT3 prevailed in kidney and lung [3].
• Expression of mouse XT3s1, but not XT3, in Xenopus laevis oocytes induced an electrogenic Na+-and-Cl--dependent transporter for proline, hydroxyproline, betaine, N-methylaminoisobutyric acid and pipecolic acid [3].

References