VANADATE AND INSULIN STIMULATE GENE-33 EXPRESSION

Vanadate and insulin stimulated gene 33 expression in rat H4 hepatoma cells. Vanadate (10-3 M) maximally increased gene 33 transcription 4-fold at 15 min. The maximal insulin induction (3-4-fold) was observed using 5×10-9 M insulin for 30 min. Both vanadate and insulin increased cytoplasmic mRNA levels in a dose-dependent manner, with maximal effects observed by 60 min. These effects on gene 33 mRNA accumulation were greater than those on transcription. Vanadate (10-3 M) maximally stimulated gene 33 mRNA levels 10-12-fold. The vanadate and insulin effects were not synergistic. Thus, high concentrations of vanadate regulate gene 33 expression in an insulin-like manner and, like insulin, vanadate probably controls transcriptional as well as post-transcriptional events. © 1992.