PI3K-Akt pathway mediated antiviral mechanism in silkworm Antheraea mylitta

Area of Science:

• * Insect molecular biology and immunology
• * Virology and host-pathogen interactions
• * Genomics and bioinformatics

Background:

• * Bombyx mori nucleopolyhedrosis virus (BmNPV) causes significant economic losses in the domestic silkworm, Bombyx mori.
• * No reports exist of NPV infection in the wild silkworm, Antheraea mylitta, suggesting potential resistance mechanisms.
• * Understanding immune responses is crucial for developing strategies against viral diseases in silkworms.

Purpose of the Study:

• * To identify immune-related proteins and pathways in Antheraea mylitta relevant to BmNPV resistance.
• * To compare gene expression profiles between resistant and susceptible Bombyx mori strains.
• * To elucidate the role of the PI3K-Akt signaling pathway in Antheraea mylitta's response to NPV infection.

Main Methods:

• * Comparative genomic analysis of Bombyx mori and Antheraea mylitta sequence datasets.
• * Gene expression analysis of resistant and susceptible Bombyx mori strains challenged with BmNPV.
• * Bioinformatic analysis using BLASTp, KEGG database, and Cytoscape; real-time PCR for Akt gene expression.

Main Results:

• * Putative defense proteins were identified as major proteins upon comparison.
• * The PI3K-Akt pathway emerged as a central signaling hub during NPV infection.
• * Real-time PCR revealed a significant upregulation of Akt expression in Antheraea mylitta post-infection, peaking at 120 hours.

Conclusions:

• * Antheraea mylitta possesses robust immune mechanisms against BmNPV, involving the PI3K-Akt pathway.
• * Upregulation of Akt indicates an enhanced immune response in Antheraea mylitta towards viral infection.
• * This study provides insights into silkworm antiviral immunity and potential targets for disease management.