title: Novel protein-tyrosine kinase cDNAs related to fps/fes and eph cloned using anti-phosphotyrosine antibody.
abstract: A rat brain lambda gt11 cDNA expression library was screened with anti-phosphotyrosine antibody to identify recombinant clones that encode enzymatically active protein-tyrosine kinases. The inserts of two bacteriophage that gave positive signals were sequenced. Both translation products possess sequence motifs characteristic of protein-tyrosine kinases. However, each polypeptide is distinct from previously described members of the tyrosine kinase family. The predicted product of the lambda B1 clone contains a catalytic domain and C-terminal tail most closely related to the eph gene product, a presumed transmembrane receptor-like protein-tyrosine kinase. The clone lambda B2 encodes a partial SH2 domain and a kinase domain similar in organization and sequence to the fps/fes cytoplasmic protein-tyrosine kinase. These new protein-tyrosine kinases (elk and flk) are apparently members of subfamilies for which eph and fps/fes are prototypes. elk is predominantly expressed in brain, while flk RNA is widely distributed and most abundant in testes. The preferential isolation of cDNAs for previously uncharacterized protein-tyrosine kinases in a screen based on catalytic activity suggests that additional members of the protein-tyrosine kinase family remain to be identified.
authors.affiliation: Division of Molecular & Developmental Biology, Mt. Sinai Hospital Research Institute, Toronto, Ontario, Canada.
authors.forename: K
authors.initials: K
authors.lastname: Letwin
authors.forename: S P
authors.initials: SP
authors.lastname: Yee
authors.forename: T
authors.initials: T
authors.lastname: Pawson
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001921:Brain / Q000201:enzymology; D002645:Chickens; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000378:metabolism; D015681:Fusion Proteins, gag-onc / Q000096:biosynthesis*; D015870:Gene Expression; D006801:Humans; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000096:biosynthesis* / Q000378:metabolism; D009857:Oncogenes; D019000:Phosphotyrosine; D011505:Protein-Tyrosine Kinases / Q000096:biosynthesis* / Q000378:metabolism; D011519:Proto-Oncogenes; D051381:Rats; D020794:Receptor Protein-Tyrosine Kinases / Q000096:biosynthesis* / Q000378:metabolism; D036143:Receptor, EphA8; D017386:Sequence Homology, Amino Acid; D014443:Tyrosine / Q000031:analogs & derivatives / Q000032:analysis
chemical_list: D018076:DNA, Complementary; D015681:Fusion Proteins, gag-onc; D009419:Nerve Tissue Proteins; D019000:Phosphotyrosine; D014443:Tyrosine; D011505:Protein-Tyrosine Kinases; D020794:Receptor Protein-Tyrosine Kinases; D036143:Receptor, EphA8; C068415:v-fps oncogene protein, Fujinami sarcoma virus