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Geranylgeraniol causes a decrease in levels of calreticulin and tyrosine phosphorylation of a 36-kDa protein prior to the appearance of apoptotic features in HL-60 cells.

S Nakajo·M Okamoto·Y Masuda·I Sakai·S Ohsawa·K Nakaya
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Abstract

It was demonstrated recently that geranylgeraniol (GGO) has potent apoptosis-inducing activity in various lines of tumor cells, including HL-60 cells. In the present study, we found that GGO markedly inhibited the expression of a calcium-binding protein, calreticulin, prior to the induction of apoptosis in HL-60 cells. Furthermore, we also observed a significant decrease in the tyrosine phosphorylation of a 36-kDa protein that is a major tyrosine-phosphorylated protein in HL-60 cells. These findings suggest that decreases in levels of calreticulin and in the tyrosine phosphorylation of the 36-kDa protein might be associated with the induction of apoptosis by GGO in HL-60 cells.

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Amino Acid SequenceApoptosisCalcium-Binding ProteinsCalreticulinDiterpenesHL-60 CellsHumansKineticsMolecular ChaperonesMolecular WeightPeptide FragmentsPhosphoproteinsPhosphorylationPhosphotyrosineRNA, MessengerRibonucleoproteinsTime FactorsTranscription, GeneticJournal Article

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S Nakajo, M Okamoto, Y Masuda, I Sakai, S Ohsawa, K Nakaya. 1996-09-24. Geranylgeraniol causes a decrease in levels of calreticulin and tyrosine phosphorylation of a 36-kDa protein prior to the appearance of apoptotic features in HL-60 cells.. https://doi.org/10.1006/bbrc.1996.1423

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