Defective SLC3A1 causes cystinuria (CSNU)

Stable Identifier
Homo sapiens
Locations in the PathwayBrowser
SVG |   | PPTX  | SBGN
Click the image above or here to open this pathway in the Pathway Browser
Neutral and basic amino acid transport protein rBAT (SLC3A1) and b(0,+)-type amino acid transporter 1 (SLC7A9) are linked by a disulfide bridge to form system b(0,+)-like activity in the high affinity transport of neutral and dibasic amino acids and cystine. The SLC7A9:SLC3A1 heterodimer mediates the electrogenic exchange of extracellular amino acids such as L-arginine (L-Arg) and L-lysine (L-lys) and cystine (CySS-, the oxidised form of L-cysteine) for intracellular neutral amino acids such as L-leucine (L-Leu). These solute carriers are mainly expressed in the kidney and small intestine where they remove dibasic amino acids and cystine from the renal tubular and intestinal lumen respectively (Schweikhard & Ziegler 2012). Defects in SLC3A1 (or SLC7A9) can cause cystinuria (CSNU; MIM:220100), an autosomal recessive disorder characterised by impaired epithelial cell transport of cystine and dibasic amino acids in the proximal renal tubule and GI tract. The build-up and low solubility of cystine causes the formation of calculi in the urinary tract, resulting in obstructive uropathy, pyelonephritis and in severe cases, renal failure (Palacin et al. 2001, Mattoo & Goldfarb 2008, Fotiadis et al. 2013, Saravakos et al. 2014). Cystinuria is subcategorized as type A (mutations on SLC3A1) and type B (mutations on SLC7A9).
Literature References
PubMed ID Title Journal Year
24246330 Cystinuria: current diagnosis and management

Kokkinou, V, Saravakos, P, Giannatos, E

Urology 2014
23506863 The SLC3 and SLC7 families of amino acid transporters

Palacin, M, Fotiadis, D, Kanai, Y

Mol. Aspects Med. 2013
11396607 The amino acid transport system b(o,+) and cystinuria

Chillarón, J, Fernández, E, Palacin, M, Zorzano, A

Mol. Membr. Biol. 2001
23177982 Amino acid secondary transporters: toward a common transport mechanism

Schweikhard, ES, Ziegler, CM

Curr Top Membr 2012
18359399 Cystinuria

Goldfarb, DS, Mattoo, A

Semin. Nephrol. 2008
Name Identifier Synonyms
cystinuria DOID:9266
Cite Us!