Influence of cellulase gene knockdown by dsRNA interference on the development and reproduction of the pine wood nematode, Bursaphelenchus xylophilus

Abstract

Cellulase genes are very important for plant-parasitic nematodes to move and feed within their host plants. The pine wood nematode, Bursaphelenchus xylophilus, causes destructive damage by killing pine trees. In this study, by employing dsRNA interference technology, knockdown of a cellulase gene (Bx-eng-1) of B. xylophilus was achieved and the biological effects of RNAi on the nematode were observed. The result showed that, after 24 h soaking, dsRNA of the Bx-eng-1 gene was effectively delivered into the nematode causing a post-transcriptional gene silencing and decrease in cellulase activity. Moreover, the number of F1 generation offspring was reduced significantly when the dsRNA-treated nematodes were cultured on fungal mats. We consider that cellulase is important to B. xylophilus because it not only hydrolyses cellulose of plant cell wall for its parasitism and penetration in host plants, but also influences its feeding, development and propagation on fungal mats.

RNA interference in Pratylenchus coffeae: Knock down of Pc-pat-10 and Pc-unc-87 impedes migration

“…Only concentrations above 2 g/l were found to be detrimental to B. xylophilus after 24 h incubation with the control dsRNA [16]. It is possible that the discrepancy among different nematodes in their response to the dsRNA concentration may be due to the differences in their inherent ability to take up dsRNA and process these introduced dsRNA.…”

“…Today, RNAi has become an established experimental technique in a number of parasitic nematodes to investigate the function of different genes. The successful application of RNAi as tool for functional genomics has also been demonstrated in plant parasitic nematodes including the sedentary endoparasitic nematodes Globodera pallida, Heterodera glycines and Meloidogyne incognita [10][11][12][13] as well as the migratory parasitic nematodes Radopholus similis [14] and Bursaphelenchus xylophilus [15][16][17][18].…”

Functional analysis of the cellulose gene of the pine wood nematode, Bursaphelenchus xylophilus, using RNA interference

“…The efficiency of applying RNAi by soaking was reduced after inoculating into branches of a susceptible host for 20 days (Cheng et al, 2010). Molecular biology has provided new perspectives for research on pine wood nematodes and their interaction with their host.…”

Gene silencing in root lesion nematodes (Pratylenchus spp.) significantly reduces reproduction in a plant host

“…Globodera pallida and Heterodera glycines), root knot nematodes (e.g. Meloidogyne incognita, Meloidogyne hapla and Meloidogyne javanica) and migratory nematodes such as Radopholus similis and Bursaphelenchus xylophilus (Adam et al 2008;Cheng et al 2010;Haegeman et al 2009;Huang et al 2006;Park et al 2008;Rosso et al 2005;Urwin et al 2002). For these obligate parasites, uptake of exogenous dsRNA is enhanced by neurostimulants such as octopamine, resorcinol or serotonin in the soaking solution (Bakhetia et al 2005;Dubreuil et al 2007;Rosso et al 2005).…”