A C1 inhibitor ortholog from rock bream (Oplegnathus fasciatus): molecular perspectives of a central regulator in terms of its genomic arrangement, transcriptional profiles and anti-protease activities of recombinant peptide.

摘要: Abstract C1 inhibitor (C1Inh), a member of serpin superfamily, is crucial regulator the activation various plasmatic cascades associated with immunity and inflammation. This study describes identification characterization C1Inh gene from rock bream Oplegnathus fasciatus ( OfC1Inh ) at structural, expressional functional levels. The cDNA-(2245 bp) corresponding gDNA-sequences (5.2 kbp) were isolated transcriptome- BAC-libraries, respectively. Predicted amino acid sequence revealed two-domain architecture composed an N -terminal region two Ig-like domains C domain. Tertiary model disclosed its active site topology. In multi-exonic genomic arrangement , it consisted eleven exons disjoined by ten introns as observed in few other fish homologs. Our comparative analysis indicated that teleostean C1Inhs distinct their non-teleostean vertebrate counterparts terms (1) extended domains, (2) evolutionary divergence (3) exon–intron distribution. had TATA-deficient promoter putative initiator element, tandemly arranged downstream elements. Several components immune inflammatory transcriptional also predicted to exist 5′ flanking . exclusive mRNA levels liver moderate extra-hepatic tissues intimated diversified importance physiology. We provide evidence for involvement balance, based on modulated transcription upon different PAMP (lipopolysaccharide poly I:C)- or pathogen Streptococcus iniae irido virus)-challenges. A recombinantly expressed fusion protein [(r)OfC1Inh] was employed demonstrating anti-protease function OfC1Inh. (r)OfC1Inh exhibited detectable inhibitory activity against esterase thrombin, where anti-C1 role shown be potentiated heparin. Taken together, results this first line possible immunity, response(s) properties enzymes involved biological cascades.