Characterization and expression analysis of an intelectin gene from Megalobrama amblycephala with excellent bacterial binding and agglutination activity. Issue 61 (February 2017)

• Record Type: Journal Article
• Authors: Ding, Zhujin; Zhao, Xiaoheng; Zhan, Qifeng; Cui, Lei; Sun, Qianhui; Lin, Li; Wang, Weimin; Liu, Hong
• Is Part Of: Fish & shellfish immunology. Issue 61(2017)
• Page Start: 100
• Page End: 110
• Publication Date: 2017-02
• Subjects: Megalobrama amblycephala -- Blunt snout bream -- Intelectin -- Aeromonas hydrophila -- Expression -- Agglutination activity; Fishes -- Immunology -- Periodicals; Shellfish -- Immunology -- Periodicals; Poissons -- Immunologie -- Périodiques; Crustacés -- Immunologie -- Périodiques; 571.9617
• DOI: 10.1016/j.fsi.2016.12.023
• Languages: English
• ISSNs: 1050-4648

Abstract

Abstract: Intelectin is a recently discovered lectin that plays vital roles in the innate immune response, iron metabolism and early embryogenesis. The structure, expression pattern and function of intelectin in mammals and amphibians have been well studied, while not well known in fish. In this study, we cloned a intelectin ( MamINTL ) gene from blunt snout bream ( Megalobrama amblycephala ), examined its expression patterns and explored its roles in innate immune response. The MamINTL cDNA encoded 312 amino acids, with a pro-protein of 34 kDa. Sequence analysis revealed the presence of a fibrinogen-related domain and eight conserved cysteine residues in the MamINTL. The MamINTL mRNA was detectable at various developmental stages, while it increased significantly post hatching. In healthy adult M. amblycephala, MamINTL was detected in various tissues with the highest expression in the liver. Upon challenge with Aeromonas hydrophila, significantly up-regulated expression of the MamINTL mRNA was observed in the liver, spleen, kidney, intestine and gill. In addition, increased level of MamINTL protein detected by Western Blotting was also observed in the liver, kidney and spleen, indicating the participation of MamINTL in the immune response. Immunohistochemistry analysis of the M. amblycephala liver sections showed significant changes in expression and location post infection. In addition, the recombinant MamINTL showed excellent binding and agglutination activity against GFP-expressed E. coli in a Ca 2+ -dependent manner. Generally, the present study provides clues for a better understanding of the characterization, expression patterns and functions of fish intelectins. Highlights: Megalobrama amblycephala intelectin ( MamINTL ) gene was cloned and characterized. The expression of MamINTL during development, in various tissues and upon infection was detected. Western Blot and immunochemistry assay was conducted to examine the levels and distribution of MamINTL upon infection. The binding and agglutination activity of recombinant MamINTL was examined.