title: A novel type III crustin (CrusEs2) identified from Chinese mitten crab Eriocheir sinensis.
abstract: Antimicrobial peptides are important effectors in the host innate immune response against microbial invasion. In the present study, the cDNA encoding a crustin (designated CrusEs2) was cloned from Chinese mitten crab Eriocheir sinensis by using EST analysis and rapid amplification of cDNA ends (RACE) approach. The full-length cDNA of CrusEs2 was of 1237 bp, containing a 5' untranslated region (UTR) of 12 bp, a 3' UTR of 886 bp with a poly (A) tail, and an open reading frame (ORF) of 339 bp encoding a polypeptide of 112 amino acids with a signal peptide of 19 amino acids. The CrusEs2 contained a typical WAP domain, but lacked the Gly-rich domain of the type II crustin and the Cys-rich region present in both type I and type II crustin, suggesting that CrusEs2 should be classified as a type III crustin. The mRNA transcripts of CrusEs2 could be detected in haemocytes and gill, and its expression level in haemocytes was up-regulated after Listonella anguillarum challenge, while decreased after Micrococcus luteus challenge. The mature peptide coding region of CrusEs2 was cloned into pET-21a+ and expressed in Escherichia coli. The purified recombinant CrusEs2 inhibited the growth of Gram-positive bacteria at MIC of 0.093-0.37 μM. The results indicated that CrusEs2 was involved in immune response of E. sinensis against bacterial challenge.
authors.affiliation: Key laboratory of Experimental Marine biology, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Rd., Qingdao 266071, China.
authors.forename: Changkao
authors.initials: C
authors.lastname: Mu
authors.forename: Peilin
authors.initials: P
authors.lastname: Zheng
authors.forename: Jianmin
authors.initials: J
authors.lastname: Zhao
authors.forename: Lingling
authors.initials: L
authors.lastname: Wang
authors.forename: Limei
authors.initials: L
authors.lastname: Qiu
authors.forename: Huan
authors.initials: H
authors.lastname: Zhang
authors.forename: Yunchao
authors.initials: Y
authors.lastname: Gai
authors.forename: Linsheng
authors.initials: L
authors.lastname: Song
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000235:genetics* / Q000302:isolation & purification; D001483:Base Sequence; D003386:Brachyura / Q000235:genetics* / Q000276:immunology* / Q000378:metabolism / Q000382:microbiology; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics; D020224:Expressed Sequence Tags; D007113:Immunity, Innate; D053526:Listonella / Q000502:physiology*; D016982:Micrococcus luteus / Q000502:physiology*; D008969:Molecular Sequence Data; D010802:Phylogeny; D012333:RNA, Messenger / Q000235:genetics; D011994:Recombinant Proteins / Q000235:genetics / Q000302:isolation & purification; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA
chemical_list: D023181:Antimicrobial Cationic Peptides; D018076:DNA, Complementary; D012333:RNA, Messenger; D011994:Recombinant Proteins