Guillaume Tetreau and Renaud Stalinski contributed equally to this work.
INCREASE IN LARVAL GUT PROTEOLYTIC ACTIVITIES AND Bti RESISTANCE IN THE DENGUE FEVER MOSQUITO
Version of Record online: 27 NOV 2012
© 2012 Wiley Periodicals, Inc.
Archives of Insect Biochemistry and Physiology
Volume 82, Issue 2, pages 71–83, February 2013
How to Cite
Tetreau, G., Stalinski, R., David, J.-P. and Després, L. (2013), INCREASE IN LARVAL GUT PROTEOLYTIC ACTIVITIES AND Bti RESISTANCE IN THE DENGUE FEVER MOSQUITO. Arch. Insect Biochem. Physiol., 82: 71–83. doi: 10.1002/arch.21076
The authors declare that no conflict of interest exists.
Grant sponsor: French National Research Agency and French Rhône-Alpes region.
- Issue online: 8 JAN 2013
- Version of Record online: 27 NOV 2012
- French National Research Agency
- French Ministry of Research
- French Rhône-Alpes region
- B. thuringiensis israelensis;
- gut extracts;
- proteolytic activities;
The bioinsecticide Bacillus thuringiensis var. israelensis (Bti) is increasingly used worldwide for mosquito control. Although no established resistance to Bti has been described in the field so far, a resistant Aedes aegypti strain (LiTOX strain) was selected in the laboratory using field-collected leaf litter containing Bti toxins. This selected strain exhibits a moderate resistance level to Bti, but a high resistance level to individual Cry toxins. As Bti contains four different toxins, generalist resistance mechanisms affecting mosquito tolerance to different toxins were expected in the resistant strain. In the present work, we show that the resistant strain exhibits an increase of various gut proteolytic activities including trypsins, leucine-aminopeptidases, and carboxypeptidase A activities. These elevated proteolytic activities resulted in a faster activation of Cry4Aa protoxins while Cry4Ba or Cry11Aa were not affected. These results suggest that changes in proteolytic activities may contribute to Bti resistance in mosquitoes together with other mechanisms.