title: A single whey acidic protein domain containing protein (SWD) inhibits bacteria invasion and dissemination in shrimp Marsupenaeus japonicus.
abstract: The single whey acidic protein (WAP) domain containing proteins (SWDs) in crustacean belong to type III crustins and have antiprotease activities and/or antimicrobial activities. Their functions in vivo in crustacean immunity need to be clarify. In this study, a new single WAP domain containing protein (SWD) was obtained from Marsupenaeus japonicus, designated as MjSWD. The full-length cDNA of MjSWD was 522 bp.The open reading frame of MjSWD encoded a protein of 79 amino acids, with a 24 amino acid signal peptide and a WAP domain. Tissue distribution analysis revealed that MjSWD transcripts were generally expressed in all the tested tissues, including hemocytes, heart, hepatopancreas, gill, stomach and intestine. The time course expression of MjSWD was analyzed by quantitative real time PCR, and the results exhibited that MjSWD was upregulated after bacteria (Vibrio anguillarum, Staphylococcus aureus) and white spot syndrome virus (WSSV) challenge in gills and stomach of the shrimp. The purified recombinant protein of MjSWD could bind to several Gram-negative and Gram-positive bacteria though binding to microbial polysaccharides (peptidoglycan). MjSWD could inhibit the activity of Subtilisin A and Proteinase K and bacteria-secreted proteases. The results of natural infection with MjSWD incubated bacteria showed that the inhibition of MjSWD against bacterial secreted proteases was contributed to inhibiting bacteria invasion and dissemination in the shrimp. The MjSWD is, thus, involved in the shrimp antibacterial innate immunity.
authors.affiliation: Key Laboratory of Plant Cell Engineering and Germplasm Innovation of Ministry of Education, School of Life Sciences, Shandong University, Jinan, Shandong 250100, China.
authors.forename: Hai-Shan
authors.initials: HS
authors.lastname: Jiang
authors.forename: Chen
authors.initials: C
authors.lastname: Sun
authors.forename: Tong
authors.initials: T
authors.lastname: Wang
authors.forename: Xiao-Fan
authors.initials: XF
authors.lastname: Zhao
authors.forename: Jin-Xing
authors.initials: JX
authors.lastname: Wang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D060829:Arthropod Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D018076:DNA, Complementary / Q000235:genetics / Q000378:metabolism; D006090:Gram-Negative Bacteria / Q000502:physiology; D006094:Gram-Positive Bacteria / Q000502:physiology; D008894:Milk Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D009928:Organ Specificity; D033561:Penaeidae / Q000201:enzymology / Q000235:genetics* / Q000276:immunology*; D010802:Phylogeny; D016133:Polymerase Chain Reaction / Q000662:veterinary; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment / Q000662:veterinary; D046848:White spot syndrome virus 1 / Q000502:physiology
chemical_list: D060829:Arthropod Proteins; D018076:DNA, Complementary; D008894:Milk Proteins; D012333:RNA, Messenger; D011994:Recombinant Proteins; C024471:whey acidic proteins
keywords: Bacteria invasion and dissemination; Marsupenaeus japonicus; Microorganism binding activity; Protease inhibitory activity; Whey acidic protein