Two glycine transporter variants with distinct localization in the CNS and peripheral tissues are encoded by a common gene.
We have isolated a cDNA encoding a high affinity, Na+/Cl(-)-dependent glycine transporter, GLYT-2, which is distinct from another glycine transporter, GLYT-1. While the 3' sequences of these two cDNAs are identical, the 5' noncoding regions and the N-termini are completely different. GLYT-1 is found only in the white matter of the CNS, while GLYT-2 is found in the gray matter of the CNS as well as in macrophages and mast cells in peripheral tissues. Our findings suggest that tissue-specific alternative splicing or alternative promoter usage from a single gene results in two mRNA products encoding similar but distinct glycine transporters. The anatomic distribution of GLYT-2 mRNA supports the emerging status of glycine as a supraspinal neurotransmitter and suggests that glycine may function as a chemical messenger outside the CNS.
Laboratory of Cell Biology, National Institute of Mental Health, Bethesda, Maryland 20892.
B
B
Borowsky
E
E
Mezey
B J
BJ
Hoffman
D000595:Amino Acid Sequence; D026921:Amino Acid Transport Systems, Neutral; D000818:Animals; D001483:Base Sequence; D001923:Brain Chemistry; D002352:Carrier Proteins / Q000032:analysis / Q000235:genetics*; D002712:Chlorides / Q000494:pharmacology; D004247:DNA / Q000032:analysis; D014644:Genetic Variation; D050487:Glycine Plasma Membrane Transport Proteins; D006651:Histocytochemistry; D017403:In Situ Hybridization; D015471:Leukemia, Basophilic, Acute; D008407:Mast Cells / Q000737:chemistry; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D012964:Sodium / Q000494:pharmacology; D013116:Spinal Cord / Q000737:chemistry*; D014018:Tissue Distribution; D014407:Tumor Cells, Cultured
D026921:Amino Acid Transport Systems, Neutral; D002352:Carrier Proteins; D002712:Chlorides; D050487:Glycine Plasma Membrane Transport Proteins; D012333:RNA, Messenger; C493269:Slc6a5 protein, rat; C493266:Slc6a9 protein, rat; D004247:DNA; D012964:Sodium