Cloning and chromosomal localization of the human TRK-B tyrosine kinase receptor gene (NTRK2)

Genomics. 1995 Jan 20;25(2):538-46. doi: 10.1016/0888-7543(95)80055-q.


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.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Brain Chemistry
  • Chromosome Mapping
  • Chromosomes, Human, Pair 9*
  • Cloning, Molecular
  • DNA, Complementary / genetics
  • Humans
  • Hybrid Cells
  • In Situ Hybridization, Fluorescence
  • Membrane Proteins / genetics*
  • Molecular Sequence Data
  • Nerve Tissue Proteins / genetics*
  • Proto-Oncogene Proteins / genetics
  • Receptor Protein-Tyrosine Kinases / genetics
  • Receptor, Ciliary Neurotrophic Factor
  • Receptor, trkA
  • Receptors, Nerve Growth Factor / genetics
  • Sequence Alignment
  • Sequence Homology, Amino Acid


  • DNA, Complementary
  • Membrane Proteins
  • Nerve Tissue Proteins
  • Proto-Oncogene Proteins
  • Receptor, Ciliary Neurotrophic Factor
  • Receptors, Nerve Growth Factor
  • Receptor Protein-Tyrosine Kinases
  • Receptor, trkA

Associated data

  • GENBANK/P04629
  • GENBANK/P08119
  • GENBANK/U05012
  • GENBANK/U12140