title: Molecular characterization and functional analysis of a piscidin gene in large yellow croaker (Larimichthys crocea).
abstract: The piscidin family, which includes potent antimicrobial peptides with broad-spectrum activity, plays an important role in the innate immune system of fish. In this study, we cloned piscidin-5-like type 3 (Lcpis5lt3) in large yellow croaker (Larimichthys crocea). Multiple alignments with other known piscidins revealed amino acid conservation throughout the fish, especially at the signal peptide (22 amino acids). The phylogenetic tree confirmed thatLcpis5lt3and large yellow croaker piscidin-5-like proteins were grouped together to form a branch. Quantitative real-time PCR revealed thatLcpis5lt3was expressed in a wide range of tissues, including the brain, muscle, gill, head kidney, intestine, kidney, liver, and spleen. The highest mRNA expression level ofLcpis5lt3was found in the spleen. AfterVibrio alginolyticusinfection, mRNA expression was rapidly upregulated in the liver, head kidney, gill, kidney, and intestine at 4, 8, 12, and 24 h post infection (hpi), whereas there were no significant changes in the spleen. The antimicrobial spectrum showed that the synthetic mature peptide ofLcpis5lt3exhibited different activityin vitroagainst various bacteria, such asAeromonas hydrophila,V. anguillarum,V. alginolyticus,V. parahaemolyticus,Staphylococcus aureus, andListeria monocytogenes. In addition, survival rates from thein vivoassay indicated that the synthetic peptide ofLcpis5lt3increased the survival rate of large yellow croaker afterV. alginolyticuschallenge, resulting in a decline in bacterial burden and mRNA expression levels of interleukin-1β, interleukin-10, and tumor necrosis factor-α. These data suggest thatLcpis5lt3plays an important role in innate immunity in large yellow croaker and might represent a potential therapeutic agent against pathogen invasion.
authors.affiliation: Laboratory of Biochemistry and Molecular Biology, School of Marine Sciences, Ningbo University, Ningbo 315211, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Yang
authors.affiliation: Laboratory of Biochemistry and Molecular Biology, School of Marine Sciences, Ningbo University, Ningbo 315211, China.
authors.forename: Xin-Jiang
authors.initials: XJ
authors.lastname: Lu
authors.affiliation: Laboratory of Biochemistry and Molecular Biology, School of Marine Sciences, Ningbo University, Ningbo 315211, China; Collaborative Innovation Center for Zhejiang Marine High-Efficiency and Healthy Aquaculture, Ningbo University, Ningbo 315211, China.
authors.forename: Fang-Chao
authors.initials: FC
authors.lastname: Chai
authors.affiliation: Laboratory of Biochemistry and Molecular Biology, School of Marine Sciences, Ningbo University, Ningbo 315211, China; Collaborative Innovation Center for Zhejiang Marine High-Efficiency and Healthy Aquaculture, Ningbo University, Ningbo 315211, China. jchen1975@163.com.
authors.forename: Jiong
authors.initials: J
authors.lastname: Chen
mesh_terms: D016980:Aeromonas hydrophila / Q000187:drug effects; D000818:Animals; D000900:Anti-Bacterial Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D001921:Brain / Q000378:metabolism; D029941:Fish Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D005880:Gills / Q000378:metabolism; D060226:Head Kidney / Q000378:metabolism; D007413:Intestinal Mucosa / Q000378:metabolism; D007668:Kidney / Q000378:metabolism; D008089:Listeria monocytogenes / Q000187:drug effects; D008099:Liver / Q000378:metabolism; D008826:Microbial Sensitivity Tests; D010455:Peptides / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D010473:Perciformes / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics; D013154:Spleen / Q000378:metabolism; D013211:Staphylococcus aureus / Q000187:drug effects; D014733:Vibrio / Q000187:drug effects; D044149:Vibrio alginolyticus / Q000187:drug effects; D014736:Vibrio parahaemolyticus / Q000187:drug effects
chemical_list: D000900:Anti-Bacterial Agents; D029941:Fish Proteins; D010455:Peptides; D012333:RNA, Messenger
keywords: Antimicrobial activity; Large yellow croaker; Piscidin; Survival rate; Vibrio alginolyticus