Molecular characterization of two immunity-related acute-phase proteins: Haptoglobin and serum amyloid A from black rockfish (Sebastes schlegeli). Issue 2 (August 2015)

• Record Type: Journal Article
• Authors: Jayasinghe, J.D.H.E.; Elvitigala, Don Anushka Sandaruwan; Whang, Ilson; Nam, Bo-Hye; Lee, Jehee
• Is Part Of: Fish & shellfish immunology. Volume 45:Issue 2(2015:Aug.)
• Page Start: 680
• Page End: 688
• Publication Date: 2015-08
• Subjects: Haptoglobin -- Serum amyloid A -- Black rockfish -- Immune challenge -- Transcriptional response; Fishes -- Immunology -- Periodicals; Shellfish -- Immunology -- Periodicals; Poissons -- Immunologie -- Périodiques; Crustacés -- Immunologie -- Périodiques; 571.9617
• DOI: 10.1016/j.fsi.2015.05.020
• Languages: English
• ISSNs: 1050-4648

Abstract

Abstract: Haptoglobin (Hp) and serum amyloid A (SAA) are two vital proteins involved in inflammatory reactions and are classified as acute-phase proteins. They are released from hepatocytes under inflammatory conditions to protect healthy cells from being damaged by pathogens or from self-destructive mechanisms. In this study, a previously constructed black rockfish ( Sebastes schlegeli ) cDNA library was used to identify the full-length cDNA sequences of Hp and SAA homologs (RfHp and RfSAA, respectively) and characterize them at the molecular level. As expected, in silico analysis of these homologs showed the typical domain architectures of their known counterparts. Open reading frames of RfHp and RfSAA consisted of 942-bp and 313-bp DNA sequences, respectively. The derived polypeptide sequence of RfHp was composed of 313 amino acids (aa) with a predicted molecular weight of 34 kD, whereas RfSAA had a 121-amino acid sequence with a molecular weight of 13 kD. Phylogenetic analysis as well as pairwise sequence alignment results showed that RfHp was more closely related to Oreochromis mossambicus from an evolutionary perspective while RfSAA was closely related to the Epinephelus coioides ortholog. Although both genes were expressed ubiquitously in the tissues analyzed, they were particularly expressed in liver tissue, suggesting their origin in hepatocytes. Quantitative real-time PCR analysis indicated that both RfHp and RfSAA were significantly up-regulated by both bacterial and viral stimulation in liver tissue, affirming their putative importance in the acute phase of first-line host immune defenses. Highlights: Haptoglobin and serum amyloid A orthologs were identified from black rockfish. This is the first report of Haptoglobin from a fish origin. Above orthologs resembled respective domain architectures of their counterparts. These orthologs ubiquitously expressed in wide range of tissues. Their basal transcription was markedly induced under pathogenic stress.