title: Characterization and expression analysis of an intelectin gene from Megalobrama amblycephala with excellent bacterial binding and agglutination activity.
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 Ca2+-dependent manner. Generally, the present study provides clues for a better understanding of the characterization, expression patterns and functions of fish intelectins.
authors.affiliation: College of Fisheries, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan 430070, China.
authors.forename: Zhujin
authors.initials: Z
authors.lastname: Ding
authors.affiliation: College of Fisheries, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan 430070, China.
authors.forename: Xiaoheng
authors.initials: X
authors.lastname: Zhao
authors.affiliation: College of Fisheries, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan 430070, China.
authors.forename: Qifeng
authors.initials: Q
authors.lastname: Zhan
authors.affiliation: College of Fisheries, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan 430070, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Cui
authors.affiliation: College of Fisheries, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan 430070, China.
authors.forename: Qianhui
authors.initials: Q
authors.lastname: Sun
authors.affiliation: College of Fisheries, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan 430070, China.
authors.forename: Li
authors.initials: L
authors.lastname: Lin
authors.affiliation: College of Fisheries, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Weimin
authors.initials: W
authors.lastname: Wang
authors.affiliation: College of Fisheries, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan 430070, China; Collaborative Innovation Center for Efficient and Health Production of Fisheries in Hunan Province, Hunan University of Arts and Science, Hunan, Changde 415000, China. Electronic address: liuhong59@mail.hzau.edu.cn.
authors.forename: Hong
authors.initials: H
authors.lastname: Liu
mesh_terms: D016980:Aeromonas hydrophila / Q000502:physiology; D000371:Agglutination; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D003530:Cyprinidae; D018076:DNA, Complementary / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics; D005393:Fish Diseases / Q000235:genetics* / Q000276:immunology / Q000382:microbiology; D029941:Fish Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D016905:Gram-Negative Bacterial Infections / Q000235:genetics / Q000276:immunology / Q000382:microbiology / Q000662:veterinary*; D007113:Immunity, Innate; D037102:Lectins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D009928:Organ Specificity; D010802:Phylogeny; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D018076:DNA, Complementary; D029941:Fish Proteins; D037102:Lectins; D012333:RNA, Messenger; D011994:Recombinant Proteins
keywords: Aeromonas hydrophila; Agglutination activity; Blunt snout bream; Expression; Intelectin; Megalobrama amblycephala