PcTRIM23 knockdown correlates with increased WSSV replication, hepatopancreatic apoptosis, and ROS accumulation in Procambarus clarkii.

This study aimed to clone and identify the TRIM23 gene (designated as PcTRIM23) from Procambarus clarkii and investigate its immune function during white spot syndrome virus (WSSV) infection. The open reading frame (ORF) of PcTRIM23 was 1719 bp in length, encoding a 572-amino acid protein that contains a RING finger domain, two B-Box domains, a B-Box C-terminal domain (BBC) at the N-terminus and an ADP-ribosylation factor (ARF) domain at the C-terminus. PcTRIM23 exhibited the highest expression levels in the hepatopancreas and gills of P. clarkii, and its expression was significantly upregulated at 6-24 h following WSSV infection. After knocking down PcTRIM23 expression via RNA interference (RNAi), the copy number of WSSV and the transcriptional level of VP28 were markedly increased, showing a correlation between reduced PcTRIM23 expression and enhanced viral replication. Further studies revealed that PcTRIM23 knockdown induced hepatopancreatic cell apoptosis, as evidenced by the increased number of TUNEL-positive cells, mitochondrial vacuolization, the up-regulation of apoptosis-related genes including Cytochrome C (Cyt-C) and caspase-3, and the down-regulation of B-cell lymphoma/leukemia 2 (Bcl-2). In addition, PcTRIM23 knockdown led to the accumulation of reactive oxygen species (ROS) and the decreased expression of antioxidant-related genes such as Nrf2, Cu/Zn-SOD and CAT. In conclusion, our results suggest that PcTRIM23 is associated with a protective role against WSSV infection in P. clarkii, correlating with reduced cell apoptosis and enhanced antioxidant response. However, further rescue experiments are needed to establish a direct causal relationship. This study provides the first functional characterization of crayfish TRIM23 in antiviral immunity and lays a foundation for further investigation of its causal regulatory mechanisms.