An integrated transcriptomic and proteomic approach to identify the main Torymus sinensis venom components

Carmen Scieuzo,Patrizia Falabella,Chiara Ferracini,Antonio Franco,Maria Monti,Milvia Chicca,Heiko Vogel,Pietro Pucci,Alberto Alma,Rosanna Salvia,Marco Pezzi,Chiara Scapoli,Flora Cozzolino

doi:10.1038/s41598-021-84385-5

Abstract

During oviposition, ectoparasitoid wasps not only inject their eggs but also a complex mixture of proteins and peptides (venom) in order to regulate the host physiology to benefit their progeny. Although several endoparasitoid venom proteins have been identified, little is known about the components of ectoparasitoid venom. To characterize the protein composition of Torymus sinensis Kamijo (Hymenoptera: Torymidae) venom, we used an integrated transcriptomic and proteomic approach and identified 143 venom proteins. Moreover, focusing on venom gland transcriptome, we selected additional 52 transcripts encoding putative venom proteins. As in other parasitoid venoms, hydrolases, including proteases, phosphatases, esterases, and nucleases, constitute the most abundant families in T. sinensis venom, followed by protease inhibitors. These proteins are potentially involved in the complex parasitic syndrome, with different effects on the immune system, physiological processes and development of the host, and contribute to provide nutrients to the parasitoid progeny. Although additional in vivo studies are needed, initial findings offer important information about venom factors and their putative host effects, which are essential to ensure the success of parasitism.

Highlights

During oviposition, ectoparasitoid wasps inject their eggs and a complex mixture of proteins and peptides in order to regulate the host physiology to benefit their progeny
Whereas ectoparasitoid wasps lay their eggs on the surface of hosts or in the environment close to the host, and their larvae develop outside the host body, endoparasitoid wasps oviposit and their progeny develop inside the host h emocoel[10]
The species distribution of the top BLAST hit against the nr database for the T. sinensis venom gland transcriptome showed that the majority of obtained top hits matched N. vitripennis (Fig. 2)

Summary

Introduction

Ectoparasitoid wasps inject their eggs and a complex mixture of proteins and peptides (venom) in order to regulate the host physiology to benefit their progeny. As in other parasitoid venoms, hydrolases, including proteases, phosphatases, esterases, and nucleases, constitute the most abundant families in T. sinensis venom, followed by protease inhibitors These proteins are potentially involved in the complex parasitic syndrome, with different effects on the immune system, physiological processes and development of the host, and contribute to provide nutrients to the parasitoid progeny. After candidate venom protein identification, they can be functionally characterized to understand how they alter the host physiological processes These alterations, in combination with other parasitic factors, induce changes in the immune system, both humoral (suppression of melanization processes) and cellular (inhibition of the encapsulation of foreign bodies by the hemocytes), in reproductive processes and in the digestive system (host tissues provide suitable nutrients for the parasitoid offspring)[13,21,22,23]. Some of the venom protein components can play a paralyzing role, preserving the host tissues in response to the nutritional needs of the parasitoid progeny[24,25]

Methods

Results

Discussion

Conclusion