作者: Peter H. Seeburg , Wendy W. Colby , Daniel J. Capon , David V. Goeddel , Arthur D. Levinson
DOI: 10.1038/312071A0
关键词: Mutation 、 Mutant 、 Gene 、 Point mutation 、 Mutagenesis (molecular biology technique) 、 Peptide sequence 、 Amino acid 、 Molecular biology 、 Biology 、 Codon usage bias
摘要: Vertebrate genomes contain proto-oncogenes whose enhanced expression or alteration by mutation seems to be involved in the development of naturally occurring tumours. These activated genes, usually assayed their ability induce malignant transformation NIH 3T3 cells, are frequently related ras oncogene Harvey (Ha-ras) Kirsten (Ki-ras) murine sarcoma viruses, a third member this family (N-ras). Activation involves point which often affect codon 12 (refs 16-26) encoded 21,000-molecular weight polypeptide (p21). To provide insight into structural requirements p21 activation, we have now constructed 20 mutant c-Ha-ras1 genes vitro mutagenesis, each encoding different amino acid at 12. Analysis rat fibroblasts transfected with these altered demonstrates that all acids except glycine (which is normal cellular genes) and proline position activate p21, suggesting requirement for an alpha-helical structure region polypeptide. The morphological phenotype cells transformed can, however, depend on particular position.