title: Characterization of functional domains of p21 ras by use of chimeric genes.
abstract: Comparison of the predicted amino acid sequences of different members of the ras family in vertebrates has shown that the N-terminal 120 residues are highly conserved while the C terminus is variable. To test the possible role of the variable residues in cell transformation, chimeras were constructed containing the N-terminal 111 amino acids of the human Ha-ras EJ oncogene and the C terminus of two Drosophila ras genes. We show that one of these constructs which has only 20 conserved residues between positions 121 and 189, can transform rat-1 cells, and the transformed cells are capable of inducing lethal tumors in rats. The second construct containing the C terminus of another Drosophila ras gene exhibits a transforming capacity as well, but only after linkage to a viral transcriptional promoter. These results show that the majority of residues within the C terminus can be replaced without abolishing the transforming potential of p21 ras.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002471:Cell Transformation, Neoplastic; D002478:Cells, Cultured; D004247:DNA / Q000235:genetics; D004274:DNA, Recombinant; D004331:Drosophila melanogaster; D019204:GTP-Binding Proteins / Q000235:genetics; D006801:Humans; D009363:Neoplasm Proteins / Q000235:genetics*; D009374:Neoplasms, Experimental / Q000235:genetics*; D009857:Oncogenes; D016283:Proto-Oncogene Proteins p21(ras); D051381:Rats; D013329:Structure-Activity Relationship
chemical_list: D004274:DNA, Recombinant; D009363:Neoplasm Proteins; D004247:DNA; D019204:GTP-Binding Proteins; C501009:HRAS protein, human; D016283:Proto-Oncogene Proteins p21(ras)