A. A549 cells were heat-shocked at 42°C for 1h, DNA and protein were cross-linked with formaldehyde, and HSF1 recruitment to the HSP72 gene analyzed by ChIP assay. B. For analysis of HSP72 mRNA levels, A549 cells were heat-shocked at 42°C for 2h then switched to 37°C. Total RNA was prepared either immediately after HS or after 1, 2 or 4h recovery at 37°C and analyzed by qRT-PCR for HSP72 and standardized for GAPDH. Data are presented as mean±SE (n=4), * denotes p<0.05, in comparison to non-heat shocked controls. C. For analysis of HSP72 protein levels, cells were heat shocked at 42°C for 2h then switched to 37°C for 4h. Cells were lysed and HSP72 protein was analyzed by immunoblot and standardized to β-tubulin. Figure representative of two independent experiments.