Proteomic analyses detect higher expression of c-type lectins in imidacloprid-resistant colorado potato beetle leptinotarsa decemlineata say

Citation

Scott, I.M., Hatten, G., Tuncer, Y., Clarke, V.C., Jurcic, K., Yeung, K.K.C. (2021). Proteomic analyses detect higher expression of c-type lectins in imidacloprid-resistant colorado potato beetle leptinotarsa decemlineata say. Insects, [online] 11(1), 1-16. http://dx.doi.org/10.3390/insects12010003

Plain language summary

Afin de répondre aux préoccupations concernant la résistance aux pesticides dans l’agriculture canadienne, il convient de comprendre les mécanismes qui sous-tendent cette résistance. Dans cette étude, nous utilisons de nouvelles techniques pour évaluer les différences entre les populations de doryphores sensibles, tolérantes et résistantes à l’imidaclopride, un néonicotinoïde. Les analyses protéomiques faisant appel à la séparation sur gel et à la spectrométrie de masse à partir de tissus prélevés sur le doryphore ont permis de mesurer des différences dans le cas d’une protéine en particulier. Il a été déterminé que les doryphores résistants à l’imidaclopride présentent des taux élevés d’une protéine associée à la réponse immunitaire des insectes, ce qui n’avait été observé auparavant que chez d’autres espèces d’insectes. Cette information est importante pour les autres chercheurs qui étudient la résistance aux insecticides à l’échelle moléculaire et pour ceux qui s’intéressent à de nouvelles cibles pour lutter contre les insectes nuisibles.

Abstract

The Colorado potato beetle (CPB) is one of the most adaptable insect pests to both plant toxins and synthetic insecticides. Resistance in CPB is reported for over 50 classes of insecticides, and mechanisms of insecticide-resistance include enhanced detoxification enzymes, ABC transporters and target site mutations. Adaptation to insecticides is also associated with changes in behaviour, energy metabolism and other physiological processes seemingly unrelated to resistance but partially explained through genomic analyses. In the present study, in place of genomics, we applied 2dimensional (2-D) gel and mass spectrometry to investigate protein differences in abdominal and midgut tissue of insecticide-susceptible (S) and-resistant (R) CPB. The proteomic analyses measured constitutive differences in several proteins, but the highest match was identified as a C-type lectin (CTL), a component of innate immunity in insects. The constitutive expression of the CTL was greater in the multi-resistant (LI) strain, and the same spot was measured in both midgut and abdominal tissue. Exposure to the neonicotinoid insecticide, imidacloprid, increased the CTL spot found in the midgut but not in the abdominal tissue of the laboratory (Lab) strain. No increase in protein levels in the midgut tissue was observed in the LI or a field strain (NB) tolerant to neonicotinoids. With the exception of biopesticides, such as Bacillus thuringiensis (Bt), no previous studies have documented differences in the immune response by CTLs in insects exposed to synthetic insecticides or the fitness costs associated with expression levels of immune-related genes in insecticide-resistant strains. This study demonstrates again how CPB has been successful at adapting to insecticides, plant defenses as well as pathogens.

Publication date

2021-01-01

Author profiles