Hsp70 Expression of six lizards species in response to heat shock. Hsp70 expression in liver was determined by quantitative real time reverse transcriptase PCR at various times post-exposure. The mRNA level of Hsp70 was normalized to that of β-actin mRNA. Values are shown as means ± SE (n = 5). Significances between room temperature lizards and heat post-exposure lizards are indicated with asterisks. *P < 0.05.