Feeding-Based RNA Intereference of a Gap Gene Is Lethal to the Pea Aphid, Acyrthosiphon pisum

Abstract

The gap gene hunchback (hb) is a key regulator in the anteroposterior patterning of insects. Loss-of-function of hb resulted in segmentation defects in the next generation. In this paper, hb expression level was investigated at different developmental stages of the pea aphid, Acyrthosiphon pisum (Ap). Aphb mRNA was most early detected at the first instar stage and showed an incontinuous increase in the whole life cycle. Ingested RNA interference was performed at the second instar stage to knockdown the Aphb expression. Continuous feeding of Aphb double-stranded RNA mixed in artificial diet led to reduction of Aphb transcripts and rise of insect lethality. These results indicated that hunchback was a good RNAi target in the management of insect pests.

RNAi Efficiency, Systemic Properties, and Novel Delivery Methods for Pest Insect Control: What We Know So Far

“…Additionally, so far it is not clear on what region of the gene (coding region, 3′ or 5′ end) is ideal for dsRNA design. In the pea aphid A. pisum , no difference in mortality was observed in groups of insect fed with dsRNA matching the 5′ or 3′ end of the hunchback (hb) gene (Mao and Zeng, 2012 and reviewed by Andrade and Hunter, 2016). An apoptosis gene from the mosquito Aedes aegypti, AaeIAP1 , was knocked down more efficiently when dsRNA targeting the 3′ end was used (Pridgeon et al, 2008).…”

Biological Mechanisms Determining the Success of RNA Interference in Insects

“…Consequently, this generated high mortality rates in the pest insect population. To date, oral delivery of dsRNA was also reported to be feasible in several other insect species, including in Bactrocera dorsalis (Diptera; Li et al, 2011), A. mellifera (Hymenoptera;Hunter et al, 2010), Epiphyas postvittana (Lepidoptera; Turner et al, 2006), Spodoptera frugiperda (Lepidoptera; Griebler et al, 2008), Plutella xylostella (Lepidoptera; Bautista et al, 2009), S. litura (Borgio, 2010), Rhodnius prolixus (Hemiptera; Araujo et al, 2006), A. pisum (Hemiptera; Mao and Zeng, 2012;Pitino et al, 2011), and Reticulitermes flavipes (Isoptera; Zhou et al, 2008). A detailed overview of the different dsRNA delivery methods for in field application of the RNAi technology, including dsRNA-encoding plants and microorganisms, is presented by Yu et al (2013) and Katoch et al (2013).…”

Parental RNA interference of genes involved in embryonic development of the western corn rootworm, Diabrotica virgifera virgifera LeConte

“…Injection-based pRNAi phenotypes for hb have been observed in insects that include the milkweed bug, O. fasciatus (Liu and Kaufman, 2004), the oriental migratory locust, Locusta migratoria manilensis (He et al, 2006), and pea aphid, A. pisum (Mao et al, 2013). A feeding-based lethal (non parental) phenotype for hb has also been described in pea aphid nymphs (Mao and Zeng, 2012). Our results extend the parental RNAi effect to western corn rootworms and show that the response can be achieved by oral administration of dsRNA to adult females.…”