Cloning of the mouse and human solute carrier 22a3 (Slc22a3/SLC22A3) identifies a conserved cluster of three organic cation transporters on mouse chromosome 17 and human 6q26-q27.

Here we report the isolation of the mouse and human solute carrier genes Slc22a3/SLC22A3. Slc22a3 is specifically expressed in placenta, but the levels of expression decline toward the end of gestation. A BAC contig spanning the mouse Slc22a3 gene was constructed, and Slc22a3 was mapped between the Igf2r and Plg genes in close association with two additional members of the Slc22a gene family, mouse Slc22a1 and Slc22a2. A partial cDNA sequence of the human SLC22A3 gene was reconstituted from sequenced EST clones. SLC22A3 is expressed in first-trimester and term placenta, but also in skeletal muscle, prostate, aorta, liver, fetal lung, salivary gland, and adrenal gland. Using a somatic cell hybrid panel and a human YAC clone, SLC22A3 was mapped to the syntenic region on human chromosome 6q26-q27, between the IGF2R and APO(a)-like genes. SLC22A1 and SLC22A2 localized to the same locus, demonstrating the conservation of the close physical linkage of these three organic cation transporter genes in mouse and human. Copyright 1999 Academic Press.