Structure, expression and chromosomal mapping of TKT from man and mouse: a new subclass of receptor tyrosine kinases with a factor VIII-like domain.
Using a polymerase chain reaction-mediated approach we have characterized cDNAs from human and mouse origin representing a novel type of receptor protein tyrosine kinase (RTK). The deduced amino acid sequence (855 amino acids) of the longest open reading frame has a unique extracellular region encompassing a factor VIII-like domain, not previously described for RTKs. The most closely related RTKs are members of the neurotrophin receptors (TRK), which showed 47-49% homology with the kinase domain of the new RTK. Therefore, the new gene has been called TKT (Tyrosine-Kinase related to TRK). TKT orthologs from man and mouse were 98% similar. In both species a major transcript of 10 kb was found to be expressed at high levels in heart and lung. Low levels of this mRNA-species were detected in human brain, placenta, liver, skeletal muscle, kidney and in mouse brain and testis. Analysing human/mouse somatic cell hybrids we demonstrated that TKT segregates with human chromosome 1.
Karn
T
T
Chemotherapeutisches Forschungsinstitut, Georg-Speyer-Haus, Frankfurt, Germany.
Holtrich
U
U
Bräuninger
A
A
Böhme
B
B
Wolf
G
G
Rübsamen-Waigmann
H
H
Strebhardt
K
K
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D001923:Brain Chemistry; D002874:Chromosome Mapping; D004247:DNA / Q000032:analysis / Q000235:genetics; D005169:Factor VIII / Q000032:analysis / Q000737:chemistry* / Q000235:genetics*; D015971:Gene Expression Regulation, Enzymologic / Q000235:genetics*; D006801:Humans; D008099:Liver / Q000737:chemistry; D051379:Mice; D008969:Molecular Sequence Data; D009132:Muscles / Q000737:chemistry; D016133:Polymerase Chain Reaction; D020794:Receptor Protein-Tyrosine Kinases / Q000032:analysis / Q000737:chemistry* / Q000235:genetics*
D005169:Factor VIII; D004247:DNA; D020794:Receptor Protein-Tyrosine Kinases