Non-nematode-derived double-stranded RNAs induce profound phenotypic changes in Meloidogyne incognita and Globodera pallida infective juveniles

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

“…Toxicity of dsRNA to J2 of M. incognita was shown at 0.1 g/l after 24 h of soaking, while the same concentration had no effect on G. pallida [30]. Our results agree with the RNAi study of the migratory nematode B. xylophilus where it was shown that a gene specific RNAi phenotype can be induced by the soaking nematodes with dsRNA of Bx-myo-3 and Bx-tmy-1 at a concentration of 1 g/l [15].…”

“…There are several other reports showing that exogenous siRNAs and shRNAs can compete with each other or with endogenous miRNAs for the RNAi machinery [36,39]. RNAi studies in M. incognita and G. pallida have also shown that even non-nematode derived double stranded RNAs induce profound phenotypic changes in these nematodes [30]. In our study no abnormal phenotype or inhibitory action on movement were observed in the nematodes incubated in the dsRNA of Pc-eng for 24 h at the concentration of 1 g/l.…”

“…Earlier reports on in vitro RNAi in G. pallida, a cyst nematode and M. incognita, a root-knot nematode have shown that high concentrations of non-specific dsRNA induce profound phenotypic changes in the infective juveniles of these nematodes [30]. Therefore, in order to confirm that the disruption in P. coffeae motility observed after RNAi is the result of specific gene silencing rather than any general toxic or inhibitory action of the dsRNA, Pc-eng-1 encoding an endoglucanase that is secreted from the pharyngeal gland cells of P. coffeae was chosen as an additional control.…”

Assessment of Globodera pallida RNA Extracted from Solanum Roots

“…Amplification by PCR was performed in 20 ml reactions containing 1.5 mM MgCl 2 , 0.2 mM dNTP, 0.2 mM primers, 1 unit Taq polymerase (Invitrogen), and 1 ml undiluted cDNA using b-actin (CV579373.1) primers (Forward 59-CCGAGAAAAGATGACCCAAA-39 and Reverse 59-AAGGAGTAACCACGCTCAGTG-39; Dalzell et al, 2009) or equal micromolar amounts of other primers as indicated in Figs. S1-S3.…”

Combinatorial in vitro RNAi of two neuropeptide genes and a pharyngeal gland gene on Meloidogyne incognita

“…Urwin et al (2002) demonstrated that octopamine, a neuro active stimulant, could stimulate the oral uptake of dsRNA. Following this approach, investigation of FLP gene function through RNAi has been well documented for some key plant-parasitic nematodes (Urwin et al, 2002;Kimber et al, 2007;Dalzell et al, 2009;Atkinson et al, 2013). In vitro RNAi silencing of the two neuropeptide genes, flp-12 and flp-18, reduced the migration of J2 of M. incognita in a sand column (Dalzell et al, 2010).…”