title: A novel crustin from Marsupenaeus japonicus promotes hemocyte phagocytosis.
abstract: Crustins are cationic cysteine-rich antimicrobial peptides (AMPs) that contain multiple domains (glycine-rich, cysteine-rich, or proline-rich) at the N-terminus and whey acidic protein (WAP) domains at the C-terminus. Crustins have multiple functions, including protease inhibition and antimicrobial activity. Other functions of crustins need to be clarified. In this study, a novel crustin with a cysteine-rich region, and a single WAP domain, belonging to type I crustins, was identified in Marsupenaeus japonicus and designated as MjCru I-1. MjCru I-1 was expressed in various tissues. The expression of MjCru I-1 was upregulated in the hemocytes of shrimp challenged with bacteria. MjCru I-1 could bind to bacteria by binding to the cell wall molecules of the bacteria, such as lipopolysaccharide (LPS), peptidoglycan (PGN), and lipoteichoic acid (LTA). The synthesized WAP domain of MjCru I-1 but not synthesized Cys-rich domain has antibacterial and agglutinative activities. Scanning electron microscope assay showed that the bacterial cells treated with sMjCru I-1 appeared to be disrupted and cracked compared with those of the control samples. The knockdown of MjCru I-1 could reduce bacterial clearance and injection of MjCru I-1 could significantly increase the survival rate of shrimp infected with Vibrio anguillarum and Staphylococcus aureus compared with those of the control samples. Further study discovered that MjCru I-1 could increase the hemocyte phagocytosis against V. anguillarum and S. aureus. These results suggest that MjCru I-1 has dual functions, bactericidal and phagocytosis promoting activities, in the antibacterial immunity of shrimp.
authors.affiliation: MOE Key Laboratory of Plant Cell Engineering and Germplasm Innovation/Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Jinan, Shandong 250100, China.
authors.forename: Ning
authors.initials: N
authors.lastname: Liu
authors.affiliation: MOE Key Laboratory of Plant Cell Engineering and Germplasm Innovation/Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Jinan, Shandong 250100, China.
authors.forename: Jiang-Feng
authors.initials: JF
authors.lastname: Lan
authors.affiliation: MOE Key Laboratory of Plant Cell Engineering and Germplasm Innovation/Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Jinan, Shandong 250100, China.
authors.forename: Jie-Jie
authors.initials: JJ
authors.lastname: Sun
authors.affiliation: MOE Key Laboratory of Plant Cell Engineering and Germplasm Innovation/Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Jinan, Shandong 250100, China.
authors.forename: Wen-Ming
authors.initials: WM
authors.lastname: Jia
authors.affiliation: MOE Key Laboratory of Plant Cell Engineering and Germplasm Innovation/Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Jinan, Shandong 250100, China.
authors.forename: Xiao-Fan
authors.initials: XF
authors.lastname: Zhao
authors.affiliation: MOE Key Laboratory of Plant Cell Engineering and Germplasm Innovation/Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Jinan, Shandong 250100, China. Electronic address: jxwang86@126.com.
authors.forename: Jin-Xing
authors.initials: JX
authors.lastname: Wang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D023181:Antimicrobial Cationic Peptides / Q000235:genetics* / Q000378:metabolism* / Q000493:pharmacokinetics; D001483:Base Sequence; D002473:Cell Wall / Q000378:metabolism; D015870:Gene Expression; D006434:Hemocytes / Q000276:immunology*; D008070:Lipopolysaccharides / Q000378:metabolism; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D033561:Penaeidae / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D010457:Peptidoglycan / Q000378:metabolism; D010587:Phagocytosis / Q000276:immunology*; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D034622:RNA Interference; D034741:RNA, Small Interfering; D011994:Recombinant Proteins / Q000494:pharmacology; D017422:Sequence Analysis, DNA; D013211:Staphylococcus aureus / Q000276:immunology; D013682:Teichoic Acids / Q000378:metabolism; D015854:Up-Regulation; D014733:Vibrio / Q000276:immunology
chemical_list: D000900:Anti-Bacterial Agents; D023181:Antimicrobial Cationic Peptides; D008070:Lipopolysaccharides; D010457:Peptidoglycan; D034741:RNA, Small Interfering; D011994:Recombinant Proteins; D013682:Teichoic Acids; C009900:lipoteichoic acid
keywords: Antimicrobial peptides (AMPs); Crustin; Innate immunity; Marsupenaeus japonicus; Phagocytosis; Whey acidic protein domain (WAP)