Is the microtubule disruption-induced alteration of peroxide concentration a factor inhibiting the assembly of ribonucleoprotein stress granules?

Abstract

It has been examined whether the destruction of cell microtubules affects the increase in the intracellular hydrogen peroxide concentration caused by sodium arsenite, which induces the formation of stress ribonucleoprotein granules. As expected, sodium arsenite caused a 50% increase in hydrogen peroxide concentration in HeLa cells; on the other hand, another stress granule inducer tert-buthylhydroquinone did not affect the peroxide concentration. The disruption of microtubules by nocodazole or vinblastine also resulted in some increase in the intracellular peroxide concentration,y taxol did not affect it. The combined treatment of cells with and the microtubule stabilization by taxol did not affect it. The combined treatment of cells with arsenite and antimicrotubule drugs caused an additive effect, and the peroxide concentration increased twice or more. Thus, the inhibition of stress granule formation after microtubule disruption cannot be explained by a decrease in peroxide concentration as compared with the affect of arsenite.