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Transformation-specific decrease of phosphorylation of 80K protein, a substrate of protein kinase C, in NIH3T3 cells.

M Oh-uchida·K Yano·S Kawamoto·K Shimizu
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Abstract

Phosphorylation in normal and transformed NIH3T3 cells of the 80K protein, a specific substrate for protein kinase C, was compared by means of two-dimensional gel analysis. We obtained evidence that NIH3T3 cells transformed by the c-raf or H-ras oncogene maintained a decreased level of phosphorylation of the 80K protein, with or without phorbol ester (TPA)-stimulation, at all concentrations of serum tested while normal NIH3T3 cells maintained an elevated level of phosphorylation of the 80K protein. Furthermore, NIH3T3 cells transformed by N-ras, K-ras, src, mos or polyoma middle T antigen exhibited a decreased level of phosphorylation of the 80K protein. These events were confirmed by an analysis of a hormone-inducible H-ras transformant. Thus, phosphorylation of the 80K protein is inversely correlated with cellular transformation.

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Cell Line, TransformedEnzyme ActivationHumansMolecular WeightPhosphorylationProtein Kinase CProto-Oncogene ProteinsProto-Oncogene Proteins c-rafStomach NeoplasmsSubstrate SpecificityTetradecanoylphorbol AcetateTumor Cells, CulturedJournal ArticleResearch Support, Non-U.S. Gov't

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M Oh-uchida, K Yano, S Kawamoto, K Shimizu. 1990. Transformation-specific decrease of phosphorylation of 80K protein, a substrate of protein kinase C, in NIH3T3 cells.. https://doi.org/10.1111/j.1349-7006.1990.tb02648.x

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