title: Cloning and chromosomal localization of the human TRK-B tyrosine kinase receptor gene (NTRK2).
abstract: There is increasing evidence that neutrophins and their receptors play an important role in regulating development of both the central and the peripheral nervous systems. Human TRK-A (NTRK1) and TRK-C (NTRK3) have been cloned and sequenced, but only a truncated form of human TRK-B has been published. Therefore, we isolated complementary DNAs spanning the entire coding region of both human full-length and truncated forms of TRK-B from human brain cDNA libraries. Human full-length TRK-B codes for a protein of 822 amino acid residues. The putative mature peptide sequence is 49% homologous to human TRK-A and 55% to full-length human TRK-C, with 40% amino acid identify among TRK-A, -B, and -C. Nine of 13 cysteine residues, 4 of 12N-glycosylation sites in the extracellular domain, and 10 of 13 tyrosine residues in the intracellular domain are conserved among human TRK-A, -B, and -C. There is a cluster of 10 serine residues in the juxtamembrane region of TRK-B that is absent in TRK-A. Two major sizes of TRK-B transcripts were expressed in human brain. Northern blot analysis using probes specific for the extracellular or the tyrosine kinase domain revealed that the 9.5-kb band encodes the full-length TRK-B mRNA and the 8.0-kb band encodes the truncated form of TRK-B mRNA. By fluorescence in situ hybridization and somatic cell hybrid mapping, the human TRK-B gene was localized to chromosome 9q22.1.
authors.affiliation: Division of Oncology, Children's Hospital of Philadelphia, Pennsylvania 19104, USA.
authors.forename: A
authors.initials: A
authors.lastname: Nakagawara
authors.forename: X G
authors.initials: XG
authors.lastname: Liu
authors.forename: N
authors.initials: N
authors.lastname: Ikegaki
authors.forename: P S
authors.initials: PS
authors.lastname: White
authors.forename: D J
authors.initials: DJ
authors.lastname: Yamashiro
authors.forename: L M
authors.initials: LM
authors.lastname: Nycum
authors.forename: J A
authors.initials: JA
authors.lastname: Biegel
authors.forename: G M
authors.initials: GM
authors.lastname: Brodeur
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D001923:Brain Chemistry; D002874:Chromosome Mapping; D002899:Chromosomes, Human, Pair 9; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D006801:Humans; D006822:Hybrid Cells; D017404:In Situ Hybridization, Fluorescence; D008565:Membrane Proteins / Q000235:genetics*; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000235:genetics*; D011518:Proto-Oncogene Proteins / Q000235:genetics; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics; D020801:Receptor, Ciliary Neurotrophic Factor; D020917:Receptor, trkA; D017475:Receptors, Nerve Growth Factor / Q000235:genetics; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
chemical_list: D018076:DNA, Complementary; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D011518:Proto-Oncogene Proteins; D020801:Receptor, Ciliary Neurotrophic Factor; D017475:Receptors, Nerve Growth Factor; D020794:Receptor Protein-Tyrosine Kinases; D020917:Receptor, trkA