Molecular characterization and expression of complement factor I in Pelteobagrus vachellii during Aeromonas hydrophila infection

• Published in: Developmental and comparative immunology 2018-05, Vol.82, p.66-71
• Main Authors: Qin, Chuanjie, Gong, Quan, Wen, Zhengyong, Yuan, Dengyue
• Format: Article
• Language: English
• Subjects: 3' Untranslated regions; Aeromonas hydrophila; Amino acids; Bacterial infections; cDNA; Complement factor I; Conserved sequence; Gene expression; Immunity; Infections; Kidneys; Liver; Molecular chains; Nucleotide sequence; Pelteobagrus vachellii; Serine; Serine proteinase; Spleen; Vertebrates
• ISSN: 0145-305X; 1879-0089
• DOI: 10.1016/j.dci.2018.01.004

Complement factor I (CFI) is a novel regulatory serine protease that plays an important role in resistance to pathogen infection. In this study, the CFI gene of Pelteobagrus vachellii (Pv-CFI) was sequenced and characterized. The full-length cDNA of 2320 bp includes a 155 bp 5′-untranslated region (UTR), a 164 bp 3′-UTR, and a 2001 bp open reading frame (ORF) encoding a 667 amino acids. Multiple sequence alignment revealed five highly conserved domains with a typical modular architecture and identical active sites in vertebrates, indicating a conserved function. Pv-CFI mRNA was constitutively expressed in all examined tissues and most abundant in liver. During infection with Aeromonas hydrophila, Pv-CFI mRNA expression was significantly up-regulated in liver at 3–24 h, spleen at 3–48 h and head kidney at 3–48 h. The results suggest Pv-CFI plays an important role in resistance to pathogenic bacteria in P. vachellii. •Complement factor I was identified and characterized in Pelteobagrus vachellii.•Pv-CFI mRNA is constitutively expressed in all tissues and most abundant in liver.•Pv-CFI mRNA is up-regulated in pathogen-infected tissues.