ARN interferente: Potenciales usos en genómica funcional y control genético de hypothenemus hampei (coleoptera: Scolytinae)

Abstract

Eukaryotic organisms, including insects, have a mechanism for specific gene silencing by short sequences of double-stranded RNA (dsRNA), such a process is known as RNA interference (RNAi). The objective of this research was to follow up this technique to screen candidate genes for the genetic control of the coffee berry borer Hypothenemus hampei. A methodology of feeding by oral drops containing different dsRNAs and dsRNAs' dosages that were placed in the preoral cavity of first instar larvae was used. Then, the larvae were reared on an artificial diet supplemented with the respective dsRNA. Previously, we verified the effectiveness of the dsRNA feeding using two control strategies: a) intake of a fluorescent compound (Calcofluor™) and b) intake of a commercial mixture of protease inhibitors. The genes coding for mannanase, xylanase, cytochrome P450 mono-oxygenase (two genes), ATPase D, α-tubulin and actin, expressed in the coffee berry borer, were selected for silencing. We found that dsRNA of cytochromes P450 produced the greatest effect, causing larval mortality of 64% and 52% respectively, followed by dsRNA of mannanase and xylanase, with a mortality rate of 37% and 33%, respectively, for the highest concentration tested.