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PubMed · 2518686

Transformation suppressor genes.

M Noda·H Kitayama·S Kanazawa·S Murata·T Matsuzaki·Y Ikawa
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Abstract

Flat revertants with reduced malignancy in vivo can be isolated from Kirsten sarcoma virus-transformed NIH3T3 cells following transfection with a normal human fibroblast cDNA expression library. We have recovered from one such revertant a 1.8 kb cDNA clone, "Krev-1", that possesses revertant-inducing activity in transfection assay. The Krev-1 cDNA has the capacity to encode a protein with a calculated molecular weight of 21,000 having strong structural similarity to ras proteins (ca. 50% homology), especially in their GTP/GDP-binding, effector-binding and membrane attachment domains. Point-mutations of Krev-1 protein at the 12th and the 59th amino acid positions from the aminoterminus potentiated the transformation suppressor activity by 2-5 times, and point-mutations within the putative effector-binding domain and at the C-terminal acylation site reduced the activity.

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Amino Acid SequenceAnimalsCell Line, TransformedCell Transformation, ViralContact InhibitionDNAFibroblastsGTP-Binding ProteinsGenes, Tumor SuppressorGenes, rasHumansKirsten murine sarcoma virusMiceMolecular Sequence DataMutagenesis, Site-DirectedOncogene Protein p21(ras)Sequence Homology, Nucleic Acidrap GTP-Binding ProteinsComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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M Noda, H Kitayama, S Kanazawa, S Murata, T Matsuzaki, Y Ikawa. 1989. Transformation suppressor genes.. https://pubmed.ncbi.nlm.nih.gov/2518686/

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