Comparative Proteomic Analysis Reveals Immune Competence in Hemolymph of Bombyx mori Pupa Parasitized by Silkworm Maggot Exorista sorbillans

Abstract

The silkworm maggot, Exorista sorbillans, is a well-known larval endoparasitoid of the silkworm Bombyx mori that causes considerable damage to the silkworm cocoon crop. To gain insights into the response mechanism of the silkworm at the protein level, we applied a comparative proteomic approach to investigate proteomic differences in the hemolymph of the female silkworm pupae parasitized by E. sorbillans. In total, 50 differentially expressed proteins (DEPs) were successfully identified, of which 36 proteins were upregulated and 14 proteins were downregulated in response to parasitoid infection. These proteins are mainly involved in disease, energy metabolism, signaling pathways, and amino acid metabolism. Eight innate immune proteins were distinctly upregulated to resist maggot parasitism. Apoptosis-related proteins of cathepsin B and 14-3-3 zeta were significantly downregulated in E. sorbillans-parasitized silkworm pupae; their downregulation induces apoptosis. Quantitative PCR was used to further verify gene transcription of five DEPs, and the results are consistent at the transcriptional and proteomic levels. This was the first report on identification of possible proteins from the E. bombycis-parasitized silkworms at the late stage of parasitism, which contributes to furthering our understanding of the response mechanism of silkworms to parasitism and dipteran parasitoid biology.

Parasitism by the Tachinid Parasitoid Exorista japonica Leads to Suppression of Basal Metabolism and Activation of Immune Response in the Host Bombyx mori

“…Immune gene expression, melanization and apoptosis were activated in silkworm integumental epithelium post E. bombycis parasitization [14]. Proteomic analysis revealed that the levels of innate immune proteins and apoptosis-related proteins were induced in the hemolymph of E. sorbillans-parasitized silkworms at a late infection stage [15]. These findings demonstrated that different host tissues exhibit diverse responses to tachinid parasitoids.…”

Effect of Tachinid Parasitoid Exorista japonica on the Larval Development and Pupation of the Host Silkworm Bombyx mori

“…One cellular immune reaction against invading parasitoid eggs and larvae is encapsulation with hemocytes followed by melanization ( Yamashita et al, 2019 ; Yang et al, 2021 ). Recent studies identified enhanced expression of innate immunity components of toll and melanization pathways, cytokines or proteolytic enzymes, and oxidative reactions in B. mori following Exorista sorbillans parasitoidism ( Pradeep et al, 2013 ; Anitha et al, 2014 ; Jayaram et al, 2014 ; Makwana et al, 2017 ; Pooja et al, 2017 ; Xu et al, 2019 ). We showed here that around 35% parasitized larvae have undergone successful larval–pupal transition and around 25% of the successful pupated parasitized hosts could eliminate tachinid larvae either in larval or pupal stage and undergo successful eclosion.…”

Rhodnius prolixus Hemolymph Immuno-Physiology: Deciphering the Systemic Immune Response Triggered by Trypanosoma cruzi Establishment in the Vector Using Quantitative Proteomics

“…Since post-genomic approaches cannot be used for fluid tissues such as hemolymph, their analysis is restricted to proteomics. Indeed, several proteomics studies of fruit fly [19][20][21], silkworm [22,23], mosquitoes [24,25], and honeybee [26] hemolymph in different biological contexts (infection, nutrition, growth . .…”