Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
34
pubmed:dateCreated
1999-9-9
pubmed:databankReference
pubmed:abstractText
A Na(+)-dependent neutral and cationic amino acid transport system (B(0+)) plays an important role in many cells and tissues; however, the molecular basis for this transport system is still unknown. To identify new transporters, the expressed sequence tag database was queried, and cDNA fragments with sequence similarity to the Na(+)/Cl(-)-dependent neurotransmitter transporter family were identified. Based on these sequences, rapid amplification of cDNA ends of human mammary gland cDNA was used to obtain a cDNA of 4.5 kilobases (kb). The open reading frame encodes a 642-amino acid protein named amino acid transporter B(0+). Human ATB(0+) (hATB(0+)) is a novel member of the Na(+)/Cl(-)-dependent neurotransmitter transporter family with the highest sequence similarity to the glycine and proline transporters. Northern blot analysis identified transcripts of approximately 4.5 kb and approximately 2 kb in the lung. Another tissue survey suggests expression in the trachea, salivary gland, mammary gland, stomach, and pituitary gland. Electrophysiology and radiolabeled amino acid uptake measurements were used to functionally characterize the transporter expressed in Xenopus oocytes. hATB(0+) was found to transport both neutral and cationic amino acids, with the highest affinity for hydrophobic amino acids and the lowest affinity for proline. Amino acid transport was Na(+) and Cl(-)-dependent and was attenuated in the presence of 2-aminobicyclo-[2.2.1]-heptane-2-carboxylic acid, a system B(0+) inhibitor. These characteristics are consistent with system B(0+) amino acid transport. Thus, hATB(0+) is the first cloned B(0+) amino acid transporter.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
20
pubmed:volume
274
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
23740-5
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
Cloning and functional expression of a human Na(+) and Cl(-)-dependent neutral and cationic amino acid transporter B(0+).
pubmed:affiliation
Department of Cell and Molecular Physiology and the Curriculum in Neurobiology, University of North Carolina, Chapel Hill, North Carolina 27599, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't