Litopenaeus vannamei NF-κB is required for WSSV replication

Area of Science:

• * Molecular biology
• * Immunology
• * Aquaculture virology

Background:

• * Viruses often exploit host NF-κB pathways for replication, altering immune responses.
• * Previous studies explored Litopenaeus vannamei NF-κB (LvNF-κB) roles in White spot syndrome virus (WSSV) in vitro.
• * The in vivo interactions between LvNF-κB family proteins and WSSV replication remained unclear.

Purpose of the Study:

• * To investigate the in vivo relationship between LvNF-κB proteins, Dorsal (LvDorsal) and Relish (LvRelish), and WSSV replication.
• * To determine if WSSV replication is dependent on the activation of LvDorsal and LvRelish.

Main Methods:

• * Gene silencing using dsRNA to reduce LvDorsal and LvRelish expression in shrimp.
• * WSSV challenge assays to quantify viral loads and VP28 expression.
• * Dual-luciferase reporter assays to assess promoter activation by LvDorsal and LvRelish on WSSV genes.

Main Results:

• * WSSV challenge significantly upregulated LvDorsal and LvRelish expression in shrimp.
• * Silencing LvDorsal or LvRelish significantly reduced WSSV loads and VP28 expression.
• * Both LvDorsal and LvRelish activated WSSV promoters (WSV069 and WSV303), with LvDorsal showing higher activity on WSV069.

Conclusions:

• * WSSV infection activates LvDorsal and LvRelish in vivo.
• * WSSV replication partially relies on the activation of these shrimp NF-κB proteins.
• * LvDorsal and LvRelish are crucial components in the host response to WSSV, and WSSV exploits them for its lifecycle.