Adapting to a Hot Meal

Science Signaling  17 May 2011:
Vol. 4, Issue 173, pp. ec140
DOI: 10.1126/scisignal.4173ec140

Mosquitoes and other insects that feed on warm-blooded animals encounter rapid increases in body temperature after feeding, yet they can tolerate this heat shock. Transcriptional array studies have shown that expression of heat shock protein (HSP)–encoding genes increases after a blood meal. Benoit et al. show that several species of mosquitoes and a species of bed bug experience a rapid 10°C increase in body temperature and an increase in the protein and transcript abundance of Hsp70. Detailed examination of the response of Aedes aegypti, the mosquito that causes yellow fever, showed that the Hsp70 increase was greatest in the midgut, could be induced by injection of 37°C saline solution, and was not induced after ingestion of a cool (29°C) blood meal. Knockdown of Hsp70 by RNA interference compromised digestion (the meal remained in the gut longer) and reduced egg production, leading the authors to propose that the heat shock response is necessary to protect the enzymes and proteins of the gut cells from heat-induced damage and degradation.

J. B. Benoit, G. Lopez-Martinez, K. R. Patrick, Z. P. Phillips, T. B. Krause, D. L. Denlinger, Drinking a hot blood meal elicits a protective heat shock response in mosquitoes. Proc. Natl. Acad. Sci. U.S.A. 108, 8026–8029 (2011). [Abstract] [Full Text]