Entomotoxic action of Sambucus nigra agglutinin i in Acyrthosiphon pisum aphids and Spodoptera exigua caterpillars through caspase-3-like-dependent apoptosis
Version of Record online: 17 SEP 2010
© 2010 Wiley-Liss, Inc.
Archives of Insect Biochemistry and Physiology
Volume 75, Issue 3, pages 207–220, November 2010
How to Cite
Shahidi-Noghabi, S., Van Damme, E. J., Mahdian, K. and Smagghe, G. (2010), Entomotoxic action of Sambucus nigra agglutinin i in Acyrthosiphon pisum aphids and Spodoptera exigua caterpillars through caspase-3-like-dependent apoptosis. Arch. Insect Biochem. Physiol., 75: 207–220. doi: 10.1002/arch.20387
- Issue online: 26 OCT 2010
- Version of Record online: 17 SEP 2010
- Research Council of Ghent University (BOF-UGent); Fund for Scientific Research-Flanders
- Sambucus nigra agglutinin;
- Acyrthosiphon pisum;
- Spodoptera exigua;
- DNA fragmentation;
- caspase-3-like proteases
In this project, the toxicity and mechanism of action of the ricin-B-related lectin SNA-I from elderberry (Sambucus nigra) in the pea aphid (Acyrthosiphon pisum) and the beet armyworm (Spodoptera exigua), two important pest insects in agriculture, were studied. SNA-I is a chimeric lectin belonging to the class of ribosome-inactivating proteins and consists of an A-chain with N-glycosidase activity and a carbohydrate-binding B-chain. Incorporation of 2 mg/ml of SNA-I in the diet of neonates and adults of A. pisum caused 40–46% mortality within 2 days, while in third instars of S. exigua, the larval biomass was significantly reduced by 12% after feeding for 3 days on a diet containing 5 mg/g of SNA-I. Interestingly, extracts of the (mid)gut of treated A. pisum and S. exigua demonstrated DNA fragmentation and this was accompanied with an increase in caspase-3-like activity. The involvement of cell death or apoptosis in the entomotoxicity of SNA-I through induction of caspase-3-like activity was also confirmed by addition of the permeable caspase-3 inhibitor III in the diet, leading to a rescue of the treated aphid neonates. Finally, similar to the chimeric lectin SNA-I, the hololectin SNA-II, consisting of two carbohydrate-binding B-chains caused high mortality to neonate A. pisum aphids with an LC50 of 1.59 mg/ml, suggesting that the entomotoxic action of the lectins under study mainly relies on their carbohydrate-binding activity. © 2010 Wiley Periodicals, Inc.