Identification, functional characterization and phylogenetic analysis of double stranded RNA degrading enzymes present in the gut of the desert locust, Schistocerca gregaria

Wynant, Niels; Santos, Dulce; Verdonck, Rik; Spit, Jornt; Van Wielendaele, Pieter; Vanden Broeck, Jozef

doi:10.1016/J.IBMB.2013.12.008

Title

Identification, functional characterization and phylogenetic analysis of double stranded RNA degrading enzymes present in the gut of the desert locust, Schistocerca gregaria

Author

Wynant, Niels

Santos, Dulce

Verdonck, Rik

Spit, Jornt

Van Wielendaele, Pieter

Vanden Broeck, Jozef

Abstract

RNA interference (RNAi) has become a widely used reverse genetics tool in eukaryotes and holds great potential to contribute to the development of novel strategies for insect pest control. While previous studies clearly demonstrated that injection of dsRNA into the body cavity of the desert locust, Schistocerca gregaria, is highly effective to induce gene silencing effects, we observed that the RNAi response is much less sensitive to orally delivered dsRNA. In line with this, we report on the presence of a potent dsRNA degrading activity in the midgut juice. Four different dsRNase sequences that belong to the DNA/RNA Non-specific Nuclease superfamily were retrieved from a transcriptome database of the desert locust. Surprisingly, we have found that, in the publicly available eukaryote nucleotide sequence databases, the presence of this group of enzymes is restricted to insects and crustaceans. Nonetheless, phylogenetic analyses predict a common origin of these enzymes with the Endonuclease G (EndoG) Non-specific Nucleases that display a widespread taxonomic distribution. Moreover, in contrast to the Sg-endoG transcript, the four Sg-dsRNase transcripts appear to be specifically expressed in the gut. Finally, by means of RNAi, we provide evidence for an important contribution of dsRNase2 to the dsRNA degrading activity that is present in the gut lumen of S. gregaria. (C) 2014 Elsevier Ltd. All rights reserved.

Language

English

Source (journal)

Insect biochemistry and molecular biology. - Bristol

Publication

Bristol : 2014

ISSN

0965-1748

DOI

10.1016/J.IBMB.2013.12.008

Volume/pages

46 (2014) , p. 1-8