title: Molecular and functional characterization of CD59 from Nile tilapia (Oreochromis niloticus) involved in the immune response to Streptococcus agalactiae.
abstract: CD59, the major inhibitor of membrane attack complex, plays a crucial role in regulation of complement activation. In this paper, a CD59 gene of Nile tilapia, Oreochromis niloticus (designated as On-CD59) was cloned and its expression pattern under the stimulation of Streptococcus agalactiae was investigated. Sequence analysis showed main structural features required for complement-inhibitory activity were detected in the deduced amino acid sequence of On-CD59. In healthy Nile tilapia, the On-CD59 transcripts could be detected in all the examined tissues, with the most abundant expression in the brain. When immunized with inactivated S. agalactiae, there was a clear time-dependent expression pattern of On-CD59 in the skin, brain, head kidney, thymus and spleen, with quite different kinetic expressions. The assays for the complement-inhibitory activity suggested that recombinant On-CD59 protein had a species-selective inhibition of complement. Moreover, our works showed that recombinant On-CD59 protein may possess both binding activities to PGN and LTA and inhibiting activity of S. agalactiae. These findings indicated that On-CD59 may play important roles in the immune response to S. agalactiae in Nile tilapia.
authors: College of Fishery, Guangdong Ocean University, Zhanjiang, 524025, China; Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, Zhanjiang, 524025, China; Key Laboratory of Control for Disease of Aquatic Animals of Guangdong Higher Education Insititutes, Zhanjiang, 524025, China.
authors: Zhen
authors: Z
authors: Gan
authors: College of Fishery, Guangdong Ocean University, Zhanjiang, 524025, China; Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, Zhanjiang, 524025, China; Key Laboratory of Control for Disease of Aquatic Animals of Guangdong Higher Education Insititutes, Zhanjiang, 524025, China.
authors: Bei
authors: B
authors: Wang
authors: College of Fishery, Guangdong Ocean University, Zhanjiang, 524025, China; Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, Zhanjiang, 524025, China; Key Laboratory of Control for Disease of Aquatic Animals of Guangdong Higher Education Insititutes, Zhanjiang, 524025, China.
authors: Wei
authors: W
authors: Zhou
authors: College of Fishery, Guangdong Ocean University, Zhanjiang, 524025, China; Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, Zhanjiang, 524025, China; Key Laboratory of Control for Disease of Aquatic Animals of Guangdong Higher Education Insititutes, Zhanjiang, 524025, China. Electronic address: fishdis@163.com.
authors: Yishan
authors: Y
authors: Lu
authors: College of Fishery, Guangdong Ocean University, Zhanjiang, 524025, China; Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, Zhanjiang, 524025, China; Key Laboratory of Control for Disease of Aquatic Animals of Guangdong Higher Education Insititutes, Zhanjiang, 524025, China.
authors: Weiwei
authors: W
authors: Zhu
authors: College of Fishery, Guangdong Ocean University, Zhanjiang, 524025, China; Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, Zhanjiang, 524025, China; Key Laboratory of Control for Disease of Aquatic Animals of Guangdong Higher Education Insititutes, Zhanjiang, 524025, China.
authors: Jufen
authors: J
authors: Tang
authors: College of Fishery, Guangdong Ocean University, Zhanjiang, 524025, China; Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, Zhanjiang, 524025, China; Key Laboratory of Control for Disease of Aquatic Animals of Guangdong Higher Education Insititutes, Zhanjiang, 524025, China.
authors: JiChang
authors: J
authors: Jian
authors: Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, Zhanjiang, 524025, China; Key Laboratory of Control for Disease of Aquatic Animals of Guangdong Higher Education Insititutes, Zhanjiang, 524025, China.
authors: Zaohe
authors: Z
authors: Wu
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D023681:Cichlids / Q000235:genetics* / Q000276:immunology*; D005393:Fish Diseases / Q000276:immunology* / Q000382:microbiology; D029941:Fish Proteins / Q000737:chemistry / Q000235:genetics* / Q000276:immunology; D005786:Gene Expression Regulation; D006023:Glycoproteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D008968:Molecular Conformation; D008969:Molecular Sequence Data; D010802:Phylogeny; D016415:Sequence Alignment / Q000662:veterinary; D013290:Streptococcal Infections / Q000276:immunology / Q000382:microbiology / Q000662:veterinary*; D013292:Streptococcus agalactiae / Q000502:physiology*
chemical_list: D029941:Fish Proteins; D006023:Glycoproteins
keywords: Antimicrobial activity; CD59; Complement-inhibitory activity; Oreochromis niloticus; Streptococcus agalactiae