HSF1 and HSF3 induce heat shock response in lizard cells.

<p>(<b>A</b>) Induction of HSP70 in HSF3 knockdown cells. <i>Gekko gecko</i> GL-1 cells were infected with Ad-sh-SCR, Ad-sh-GgeHSF3-KD1, or Ad-sh-GgeHSF3-KD2 for 96 h, and were then heat shocked at 42^°C for 1 h and allowed to recover for 3 h (HS + R3) or 6 h (HS + R6). Cell extracts were prepared from these cells, and aliquots were subjected to western blotting using anti-HSP70 (anti-cHSP70a), anti-HSF3 and anti-β-actin antibodies. (<b>B</b>) Induction of HSP70 in HSF3 knockout cells. Wild-type (WT) and HSF3-null GL-1 cells (HSF3-/- clones 303 and 109) were heat-shocked at 42^°C for 1 h and allowed to recover for 3 h (HS + R3) or 6 h (HS + R6). Cell extracts were prepared and aliquots were subjected to western blotting. (<b>C</b>) Induction of HSP70 in HSF1 knockdown cells. GL-1 cells were infected with Ad-sh-SCR, Ad-sh-GgeHSF1-KD1, or Ad-sh-GgeHSF1-KD2 for 96 h, and were treated as in A. (<b>D</b>) Induction of HSP70 in HSF3 and HSF1 knockdown cells. GL-1 cells were infected with the indicated adenoviruses for 96 h, and were treated as in A. Cell extracts were prepared from these cells, and aliquots were subjected to western blotting using antibodies including anti-HSP70, anti-HSP40 (anti-hHSP40-1), and anti-HSP60 (anti-mHSP60-1) antibodies. (<b>E</b>) Cell survival under heat shock conditions. GL-1 cells were infected with Ad-sh-SCR, Ad-sh-GgeHSF1-KD1, Ad-sh-GgeHSF3-KD1, or both viruses for 96 h, and were then heat shocked at 45^°C for the indicated periods. These cells were stained with trypan blue, and percentages of surviving cells are shown (n = 3). *, p < 0.05; **, p < 0.01 by ANOVA.