Genome-Wide Identification of the TRAF Gene Family in Common Carp (Cyprinus carpio) and Analysis of Their Expression in Response to CyHV-3 Challenge

Abstract

Simple Summary Common carp (Cyprinus carpio) is one of the most economically valuable freshwater fish worldwide. Cyprinid herpesvirus 3 (CyHV-3) infection causes massive mortality and huge economic losses in carp aquaculture. Tumor necrosis factor receptor-associated factors (TRAFs) are essential signal molecules regulating innate immune and antiviral responses in teleosts. Nevertheless, the immune functions of TRAF genes in common carp against CyHV-3 remain poorly understood. In this work, we identified 16 CcTRAF genes in the common carp genome and explored their tissue distribution and expression responses upon viral challenge. CcTRAF genes are preferentially expressed in main immune organs. Under CyHV-3 challenge, CcTRAF3, CcTRAF6 and CcTRAF7 exhibited significant transcriptional changes and reached expression peaks at 48 h post-challenge. Our results indicate that CcTRAF genes participate in carp antiviral immunity. This study provides fundamental clues for understanding TRAF-mediated immune defense in common carp.