title: Antiviral function of Tachyplesin I against iridovirus and nodavirus.
abstract: Antimicrobial peptides (AMPs) are ubiquitously found in living organisms and are an important component in innate immune response. Tachyplesin I is a potent antimicrobial peptide isolated from the hemocytes of the horseshoe crab, Tachypleus tridentatus. Previous studies have shown that the 17-residue peptide exhibits a wide spectrum of antimicrobial activity against Gram-negative and Gram-positive bacteria, fungi, protozoa, and viruses. However, the efficiencies and defense mechanisms of the Tachyplesin I against fish viruses are still unknown. In this study, Tachyplesin I showed a key role in inhibiting the infection and replication of two kinds of newly emerging marine fish viruses, an enveloped DNA virus of Singapore grouper iridovirus (SGIV), and a non-enveloped RNA virus of viral nervous necrosis virus (RGNNV). Synthetic peptides of Tachyplesin I incubated with virus or cells before infection reduced the viral infectivity. Synthetic peptides of Tachyplesin I drastically decreased SGIV and RGNNV titers and viral gene expression. Grouper spleen (GS) and brain (GB) cells over-expressing Tachyplesin I (GS/pcDNA3.1-flag-Tac I and GB/pcDNA3.1-flag-Tac I) support the inhibition of viral infection. Tachyplesin I activated type I IFN and Interferon-sensitive response element (ISRE) in vitro. The promoter activity of IFN-β and ISRE were significantly up-regulated in cells transfected with pcDNA3.1-flag-Tac I after infection with SGIV and VNNV. These results suggest that Tachyplesin I is importantly involved in host immune responses to invasion of viral pathogens.
authors.affiliation: Department of Food and Bioengineering, Bengbu College, Bengbu, 233030, PR China.
authors.forename: Haiwei
authors.initials: H
authors.lastname: Xie
authors.affiliation: Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, PR China; Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, PR China.
authors.forename: Jingguang
authors.initials: J
authors.lastname: Wei
authors.affiliation: Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, PR China; College of Marine Sciences, South China Agricultural University, Guangzhou, 510642, China; Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, PR China. Electronic address: qinqw@scsio.ac.cn.
authors.forename: Qiwei
authors.initials: Q
authors.lastname: Qin
mesh_terms: D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000235:genetics / Q000378:metabolism*; D060829:Arthropod Proteins / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D006737:Horseshoe Crabs / Q000235:genetics / Q000276:immunology* / Q000821:virology*; D007370:Interferon Type I / Q000235:genetics / Q000378:metabolism; D030381:Nodaviridae / Q000502:physiology*; D010456:Peptides, Cyclic / Q000235:genetics / Q000378:metabolism*; D017995:Ranavirus / Q000502:physiology*
chemical_list: D023181:Antimicrobial Cationic Peptides; D060829:Arthropod Proteins; D004268:DNA-Binding Proteins; D007370:Interferon Type I; D010456:Peptides, Cyclic; C057636:tachyplesin peptide, Tachypleus tridentatus
keywords: Antiviral effects; Epinephelus coioides; RGNNV; SGIV; Tachyplesin I