Genomic characterization and expression analysis of complement component 9 in rock bream (Oplegnathus fasciatus)

► Rb-C9 was characterized at the genomic and transcriptional level. ► In silico analysis of promoter and transcription factor binding sites. ► Rb-C9 showed transcriptional up-regulation to infection with Edwardsiella tarda, Streptococcus iniae. ► Rb-C9 showed transcriptional up-regulation to infection with LPS and iridovirus.