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. 2009 Feb 20;4(2):e4546. doi: 10.1371/journal.pone.0004546

Figure 4. RNAi suppression of cold exposure-induced up-regulation of PaHsp70 expression and its effect on survival.

Figure 4

Relative levels of Pahsp70 mRNA (A), PaHsp70 protein (B) and Pahsc70 mRNA (C) were measured in the fat bodies of male Pyrrhocoris apterus at different times of recovery after the cold exposure to −5°C for 5 d. The insects were either untreated (control) or injected two days prior to heat shock with: 2 µL of the injection buffer alone (blank); or 2 µL (2 µg) of Pahsp70 dsRNA. (D) An example of Western blotting. (E, F) Survival in blank-injected (E, n = 49) and Pahsp70 dsRNA-injected (F, n = 48) insects after the cold exposure. (G) Cross-tolerance was assesed by observing the survival in insects (n = 48) that were pretreated with a mild heat shock (+41°C for 1 h) prior to the cold exposure to −5°C for 5 d. See Figs. 1 and 2 for more information.