Insulin-Related Peptide 5 is Involved in Regulating Embryo Development and Biochemical Composition in Pea Aphid with Wing Polyphenism

Abstract

In aphids there is a fecundity-dispersal trade-off between wingless and winged morphs. Recent research on the molecular mechanism of wing morphs associated with dispersal reveals that insulin receptors in the insulin signaling (IS) pathway regulate alternation of wing morphs in planthoppers. However, little is known about whether genes in the IS pathway are involved in developmental regulation in aphid nymphs with different wing morphs. In this study, we show that expression of the insulin-related peptide 5 gene (Apirp5) affects biochemical composition and embryo development of wingless pea aphids, Acyrthosiphon pisum. After comparing expression levels of major genes in the IS pathway between third instar winged and wingless nymphs, we found that Apirp5 showed higher expression in head and thorax in the wingless nymphs than in the winged nymphs. Although microinjection treatment affects physical performance in aphids, nymphs with RNA interference of Apirp5 had less weight, smaller embryos, and higher carbohydrate and protein contents compared to the control group. Comparison between winged and wingless nymphs showed a similar trend. These results indicate that Apirp5 is involved in embryo development and metabolic regulation in wing dimorphic pea aphid.

Expression profiling of winged‐ and wingless‐destined pea aphid embryos implicates insulin/insulin growth factor signaling in morph differences

“…Because of its effects on the expression of these genes, the IIS pathway is thought of as a phenotypic plasticity pathway, generating bodies that match their environment with respect to size, shape and physiology. Correspondingly, multiple studies have implicated the IIS pathway in the regulation of a wide variety of plasticities (Emlen, Warren, Johns, Dworkin, & Lavine, ; Snell‐Rood & Moczek, ; Tang et al, ; Wheeler, Buck, & Evans, ; Wolschin et al, ; reviewed in Nijhout and McKenna, 2018), including late nymphal stage differences between winged and wingless morphs of two aphid species (Ding et al, ; Guo, Zhang, & Liu, ), and long and short‐winged morphs of the brown planthopper, Nilaparvata lugens (Xu et al, ) and the soapberry bug, Jadera haematoloma (Fawcett et al, ). Interestingly, the latter two studies showed different functional requirements for the two insulin receptors, the paralogs InR1 and InR2.…”

Vitellogenin and its receptor play essential roles in the development and reproduction of the brown citrus aphid, Aphis (Toxoptera) citricidus

“…Aphids are major agricultural pests that cause significant losses of crop plants by feeding from plant phloem and transmitting harmful plant viruses (Yu et al, 2016). Aphids with wing dimorphism (apterous and alate) reflect a trade-off between fecundity and migration (Guo et al, 2016). In Acyrthosiphon pisum, embryos develop faster in the ovaries of apterous aphids than in the ovaries of alate aphids (Guo et al, 2016).…”

“…Aphids with wing dimorphism (apterous and alate) reflect a trade-off between fecundity and migration (Guo et al, 2016). In Acyrthosiphon pisum, embryos develop faster in the ovaries of apterous aphids than in the ovaries of alate aphids (Guo et al, 2016). Although aphids are high-fecundity insect species with pseudoplacental viviparity, their Vg and the receptor VgR have not been characterized.…”

Transcriptome profiling of maternal stress‐induced wing dimorphism in pea aphids

“…On the contrary, ecdysone signaling suppressed by RNA interference targeting the ecdysone receptor (EcR) or by an EcR antagonist decreased the proportion of winged offspring. Insulin‐related peptide 5 gene ( Apirp5 ) regulated the alternation of wing morphs in pea aphids by affecting some physiological phenotypes such as body weight, embryo size, and carbohydrate and protein contents (Guo, Zhang, & Liu, ). The insulin signaling pathway could be also involved in the regulation of wing development in pea aphid.…”