Molecular Characterization and Expression Analysis of the C-Type Lectin Domain Family 4 Member F in against White Spot Syndrome Virus.

White spot disease (WSD) outbreaks pose a significant threat to the Pacific white shrimp () farming industry. The causative agent is the white spot syndrome virus (WSSV). There are no effective treatments for WSD so far. Therefore, understanding the resistance mechanisms of . against the WSSV is crucial. C-type lectins (CTLs) are important pattern recognition receptors (PRRs) that promote agglutination, phagocytosis, encapsulation, bacteriostasis, and antiviral infections. This study cloned the C-type lectin domain family 4 member F () from . . contains a 492 bp open reading frame (ORF) encoding a protein of 163 amino acids, including a carbohydrate recognition domain (CRD). Following a challenge with the WSSV, the expression profile of was significantly altered. Using RNA interference (RNAi) technology, it was found that promotes WSSV replication and affects the expression levels of genes related to the regulation of apoptosis, signaling and cellular stress response, and immune defense. Meanwhile, the hemolymph agglutination phenomenon in vivo was weakened when was knocked down. These results indicated that may play an important role in the interaction between . and WSSV.