Genome-wide identification and characterization of COMMD family genes reveals their function on innate immune response in Paralichthys olivaceus

Abstract The COMMD (Copper Metabolism gene MuRR1 Domain) gene family, containing the COMM domain, is highly conserved in diverse lineages and participate in many cellular and biological processes, such as iron transport, regulation of NF-κB activity, and cell proliferation. However, the characteristics and functions of COMMD family are never described in teleost species. Here, we identified all ten COMMD family members in Japanese flounder (Paralichthys olivaceus) based on the genomic and transcriptomic data. COMMD members displayed diverse expression patterns in eleven investigated tissues of Japanese flounder. The regulation of COMMDs in Japanese flounder exposed to Edwardsiella tarda challenge in three immune-related organs, liver, intestine and gill suggested their possible role in innate immune response. Moreover, the expression levels of COMMDs were also significantly up-regulated after LPS stimulation in gill cell line. We further confirmed that PoCOMMD1 could suppress the activity of NF-κB through COMM domain. Taken together, our study elaborates the characteristics and functions of COMMDs in innate immune response of a teleost species. This adds more information for understanding the evolutionary dynamics and immune-related functions of COMMD family in teleost.