XB-ART-1833Gene Expr Patterns. August 1, 2005; 5 (6): 774-7.
Amino acid cotransporter SLC3A2 is selectively expressed in the early proximal segment of Xenopus pronephric kidney nephrons.
The transport of amino acids across membranes is critical to all cells. As amino acids freely pass through the glomerular filtration barrier of the kidney, they must be efficiently resorbed to avoid depletion of circulating amino acid reserves. Not only do defects in amino acid resorption lead to costly wastage, they also cause congenital aminoacidurias. A clone encoding Xenopus SLC3A2 was identified and shown to be expressed at high levels in the early segment of the pronephric proximal tubules in developing tadpoles. The type II membrane glycoprotein encoded by this gene can associate with a wide variety of protein partners and participates in a broad spectrum of biological processes. In this report, the first whole-mount analysis of SLC3A2 during early embryonic development is presented. The expression pattern of SLC3A2 in the early proximal segment of the Xenopus pronephros is analogous to that of a previously described SLC7A8/XAA2 amino acid transporter. In mammals, SLC3A2 and SLC7A8/XAA2 associate to form a functional neutral amino acid transporter complex and coexpression of these two genes in a small domain within the pronephric tubules indicates that this is also the situation in the developing Xenopus kidney.
PubMed ID: 15923149
Article link: Gene Expr Patterns.
Genes referenced: atp1a1 slc3a2 slc7a8
Article Images: [+] show captions
|Fig. 2. Expression of Xenopus SLC3A2 in the pronephros. Panels A–H illustrate SLC3A2 expression in Xenopus laevis embryos of various stages, which are indicated in the lower right of each panel. Detection is via colorimetic in situ hybridization. Panels I and J are FCIS overlays, where colorimetic SLC3A2 expression (blue) has been counter-stained for Na+K+ATPase expression via FISH. Good overlap appears blue or blue/purple (black arrow), weak overlap appears pink (blue arrow), and no overlap appears orange. Panels K and L illustrate FISH data. K is SLC3A2 expression alone developed with a green substrate, while L is an overlay illustrating SLC3A2 expression as green, Na+K+ATPase expression as red, and coexpression as yellow. Most overlap occurs in the early proximal domain (black arrow), but a low level of coexpression is also observed in the late proximal domain (blue arrow).|
|slc3a2 in stage 36 Xenopus laevis embryo. This is a FCIS double stain with slc3a2 in blue/magenta and atp1a1 in orange|