Cloning, expression, and localization of a rat brain high-affinity glycine transporter.
A cDNA clone encoding a glycine transporter has been isolated from rat brain by a combined PCR and plaque-hybridization strategy. mRNA synthesized from this clone (designated GLYT1) directs the expression of sodium- and chloride-dependent, high-affinity uptake of [3H]glycine by Xenopus oocytes. [3H]Glycine transport mediated by clone GLYT1 is blocked by sarcosine but is not blocked by methyl-aminoisobutyric acid or L-alanine, a substrate specificity similar to that described for a previously identified glycine-uptake system called system Gly. In situ hybridization reveals that GLYT1 is prominently expressed in the cervical spinal cord and brainstem, two regions of the central nervous system where glycine is a putative neurotransmitter. GLYT1 is also strongly expressed in the cerebellum and olfactory bulb and is expressed at lower levels in other brain regions. The open reading frame of the GLYT1 cDNA predicts a protein containing 633 amino acids with a molecular mass of approximately 70 kDA. The primary structure and hydropathicity profile of GLYT1 protein reveal that this protein is a member of the sodium- and chloride-dependent superfamily of transporters that utilize neurotransmitters and related substances as substrates.
Division of Biology, California Institute of Technology, Pasadena 91125.
J
J
Guastella
N
N
Brecha
C
C
Weigmann
H A
HA
Lester
N
N
Davidson
D000595:Amino Acid Sequence; D026921:Amino Acid Transport Systems, Neutral; D000818:Animals; D001483:Base Sequence; D001921:Brain / Q000378:metabolism*; D002352:Carrier Proteins / Q000032:analysis / Q000235:genetics* / Q000378:metabolism; D003001:Cloning, Molecular; D005971:Glutamates / Q000378:metabolism; D018698:Glutamic Acid; D005998:Glycine / Q000378:metabolism*; D050487:Glycine Plasma Membrane Transport Proteins; D007700:Kinetics; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides; D009865:Oocytes / Q000378:metabolism; D016133:Polymerase Chain Reaction / Q000379:methods; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D051381:Rats; D012689:Sequence Homology, Nucleic Acid; D013116:Spinal Cord / Q000378:metabolism*; D014981:Xenopus; D015091:beta-Alanine / Q000378:metabolism; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
D026921:Amino Acid Transport Systems, Neutral; D002352:Carrier Proteins; D005971:Glutamates; D050487:Glycine Plasma Membrane Transport Proteins; D009838:Oligodeoxyribonucleotides; D012333:RNA, Messenger; C493266:Slc6a9 protein, rat; D015091:beta-Alanine; D018698:Glutamic Acid; D005680:gamma-Aminobutyric Acid; D005998:Glycine