Consequences of genetic and pharmacological blockade of protein degradation pathways on the regulation of HSF1.

<p>(A) Effects of riluzole on HSF1 in NIH-3T3 versus Lamp2A RNAi-knockdown cells. Cells in 60 mm plates were treated with 2 μM riluzole at 37°C for 16 hr. For heat shock, cells were placed in a 42°C incubator for 2 hrs. Cells were harvested and aliquots of the RIPA cell extracts containing 10 μg protein were used for immuno-Western blot analysis of HSF1 according to methods described in the text. The position on the gel of the HSF1 and of the heat induced hyperphosphorylated HSF1 is indicated by an *. The relative abundance of the HSF1 protein is indicated at the bottom of the figure. (B) Effects of chloroquine on HSF1. HeLa cells were treated with 0.2 mM chloroquine at 37°C for time periods as indicated. Aliquots of the RIPA cell extract were used for immuno-Western blot detection of HSF1. Extracts from control and heat-shocked cells were included as controls. The position on the gel of the HSF1 and of the heat induced hyperphosphorylated HSF1 is indicated by an *.