Structure of the human lck gene: differences in genomic organisation within src-related genes affect only N-terminal exons.
Although cDNA sequences coding for several Rous sarcoma virus Src-related protein tyrosine kinases (PTKs) have been reported for several years, knowledge of the structure and organisation of genes of the src family is still limited. In this work, a detailed structure and organisation of the human lck gene is reported. A 17-kb genomic clone encoding human p56 Lck, a lymphocyte-specific PTK of the Src-related subfamily, has been isolated. The human lck gene is organized in 13 exons, one more than in the human cellular (c)-src gene. The twelve coding exons are located in this clone, whereas the putative 5'-noncoding exon is probably located very far upstream from the second exon. Splicing sites for exons 4 to 12, which encode both conserved phospholipase-C-like and catalytic domains of the Src-like PTKs, arise exactly at the same position for the human lck, human c-src and c-fgr genes. The only differences concern the splice sites of exons 1' and 2, which encode the unique N-terminal domain of human Lck. These results give further evidence that the different PTKs of the Src-like family have probably evolved through the mechanism of exon shuffling.
Rouer
E
E
Institut National de la Santé et de la Recherche Médicale (INSERM U15), Paris, France.
Van Huynh
T
T
Lavareda de Souza
S
S
Lang
M C
MC
Fischer
S
S
Benarous
R
R
D000595:Amino Acid Sequence; D001358:Avian Sarcoma Viruses / Q000201:enzymology / Q000235:genetics*; D001483:Base Sequence; D003001:Cloning, Molecular; D005091:Exons; D005796:Genes; D015894:Genome, Human; D006801:Humans; D007438:Introns; D008969:Molecular Sequence Data; D005810:Multigene Family; D009856:Oncogene Proteins, Viral / Q000235:genetics*; D011505:Protein-Tyrosine Kinases / Q000235:genetics*; D012326:RNA Splicing; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid; D013601:T-Lymphocytes / Q000201:enzymology
D009856:Oncogene Proteins, Viral; D011505:Protein-Tyrosine Kinases