A serpin (CvT‐serpin15) of teratocytes contributes to microbial‐resistance in Plutella xylostella during Cotesia vestalis parasitism

Abstract

BACKGROUND Parasitic wasps are an important group of entomophagous insects for pest control. As parasitic wasps often lay eggs on or into their associated hosts, parasitoids evolve to utilize several factors including venom, polydnavirus (PDV) to alter host physiology for successful parasitism. Some taxa of endoparasitoids produce teratocytes, which are a type of cell that is released into host insects when wasp eggs hatch. Teratocytes display multifunction in parasitism such as host nutritional exploration, immune and developmental regulation, by secreting plenty of proteins into host hemocoel. RESULTS A serpin (CvT‐serpin15) secreted by teratocytes was characterized. QPCR results showed the expressional level of CvT‐serpin15 was upregulated following bacterial challenges. Enzyme activity experiment indicated the recombinant CvT‐serpin15 protein could interfere with the growth of Gram‐positive bacteria Staphylococcus aureus. The survival rate assay demonstrated CvT‐serpin15 increased survival rate of Plutella xylostella infected by S. aureus. CONCLUSION CvT‐serpin15 secreted by teratocytes would boost the host immune system when pathogens invade host hemocoel during parasitism, and ultimately protect the development of wasp larva from bacterial infection. © 2021 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

A parasitoid serpin gene that disrupts host immunity shows adaptive evolution of alternative splicing

“…To manipulate their hosts, parasitoid wasps often recruit effector genes, e.g., venom or larval salivary genes 14,15 . Serpin, a common component of parasitoid venom 17, 20–23, 33–41 , has also been reported in teratocytes of parasitoid wasps for host regulation 53,54 . Here, we further extend serpin recruitment to wasp larval saliva.…”

“…The copyright holder for this preprint this version posted March 29, 2023. ; https://doi.org/10.1101/2023.03.28.534536 doi: bioRxiv preprint larval salivary genes 14,15 . Serpin, a common component of parasitoid venom 17,[20][21][22][23][33][34][35][36][37][38][39][40][41] , has also been reported in teratocytes of parasitoid wasps for host regulation 53,54 . Here, we further extend serpin recruitment to wasp larval saliva.…”

Immunosuppressive, antimicrobial and insecticidal activities of inhibitor cystine knot peptides produced by teratocytes of the endoparasitoid wasp Cotesia flavipes (Hymenoptera: Braconidae)

“…For instance, defensins are broad-spectrum antibacterial peptides released by teratocytes in order to maintain an infection-free environment for successful parasitoid larval development (Gao et al, 2016). Several other antimicrobial proteins are released by teratocytes such as chitinases (Falabella, 2018), chitolectins (Rossi et al, 2012), apolipoproteins (Salvia et al, 2022), and serine protease inhibitors (Gu et al, 2021). In this study, we associated a new class of molecules, the ICK peptides, as antimicrobial peptides produced by the teratocytes of the parasitoid C. flavipes.…”

“…, 2022), and serine protease inhibitors (Gu et al. , 2021). In this study, we associated a new class of molecules, the ICK peptides, as antimicrobial peptides produced by the teratocytes of the parasitoid C. flavipes .…”

Serine protease mediates Ovomermis sinensis‐inhibited host immune responses by inducing apoptosis: implications for successful parasitism and host mortality

“…[8][9][10][11][12][13] Interestingly, parasitoid wasps use virulent proteins, venom, and polydnaviruses to overcome host immunity and kill the host. [14][15][16][17][18] 18 Therefore, parasites passively escape or actively control host immunity using virulence factors. 1,3 Mermithid nematodes are entomopathogens that infect a broad range of insect pests, including lepidopteran pests and mosquitoes, thus providing biological control of insect pests.…”