Structure of the Ki-ras gene of the human lung carcinoma cell line Calu-1

Nature. 1983 Aug 11-17;304(5926):497-500. doi: 10.1038/304497a0.


The homologue of the viral Kirsten ras (v-Ki-ras) gene found in the human lung carcinoma cell line, Calu-1, has an intron-exon structure similar to that of the human homologue of the viral Harvey ras (v-Ha-ras) gene. A second, potential fourth coding exon is present in the human Ki-ras gene and similar sequences are found in the Kirsten murine sarcoma virus. Cysteine is encoded at the twelfth amino acid position, suggesting that the Calu-1 Ki-ras gene has undergone a mutational activation at the same position as the human Ha-ras gene of the bladder carcinoma cell line, T24. A comparison of their predicted amino acid sequences suggests that ras proteins have a 'constant' region and a 'variable' region. Here we propose a common modular structure for ras gene products in which the variable region forms a physiologically important combining site.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Carcinoma / genetics*
  • Cell Line
  • Cell Transformation, Viral*
  • Genes, Viral*
  • Humans
  • Kirsten murine sarcoma virus / genetics*
  • Lung Neoplasms / genetics*
  • Oncogenes*
  • Sarcoma Viruses, Murine / genetics*
  • Viral Proteins / genetics


  • Viral Proteins

Associated data

  • GENBANK/K00652
  • GENBANK/K00653
  • GENBANK/L00045
  • GENBANK/L00046
  • GENBANK/L00047
  • GENBANK/L00048
  • GENBANK/L00049