YHV-responsive gene expression under the influence of PmRelish regulation

Area of Science:

• * Innate immunity
• * Molecular biology
• * Animal virology

Background:

• * The Imd signaling pathway is vital for animal defense against Gram-negative bacteria and viruses.
• * Relish, an NF-κB transcription factor, is a key regulator of antimicrobial protein synthesis in this pathway.
• * Yellow head virus (YHV) infection in shrimp activates the Imd pathway, highlighting the need to understand gene regulation.

Purpose of the Study:

• * To investigate gene expression during YHV infection under PmRelish regulation.
• * To identify genes controlled by PmRelish in shrimp immunity.
• * To elucidate the role of PmRelish in the Imd pathway's response to viral and bacterial challenges.

Main Methods:

• * RNA interference (RNAi) was used to knockdown PmRelish expression.
• * Suppression subtractive hybridization (SSH) generated cDNA libraries to compare gene expression profiles.
• * Gene expression was analyzed via nucleotide sequencing, BLAST annotation, and quantitative analysis of specific antimicrobial protein genes.

Main Results:

• * SSH identified 252 and 99 cDNA clones from forward and reverse libraries, respectively.
• * Genes related to defense and homeostasis, including antimicrobial proteins, proteinases, and inhibitors, were abundant.
• * PmRelish silencing affected the expression of penaeidin5 and penaeidin3, but not ALFPm3 or crustinPm1, during YHV and Vibrio harveyi infections.

Conclusions:

• * PmRelish plays a regulatory role in the Imd pathway's response to YHV infection.
• * Specific penaeidin genes (penaeidin5 and penaeidin3) are under PmRelish control.
• * This study provides insights into shrimp antiviral immunity and the specific functions of PmRelish in regulating defense genes.