title: Molecular cloning and expression analysis of Ch-penaeidin, an antimicrobial peptide from Chinese shrimp, Fenneropenaeus chinensis.
abstract: A new member of antimicrobial peptide genes of the penaeidin family, Ch-penaeidin, has been cloned from the haemocytes of Chinese shrimp, Fenneropenaeus chinensis, by reverse transcription PCR (RT-PCR), 3'-rapid amplification of cDNA end (3'-RACE) and smart cDNA methods. The Ch-penaeidin cDNA was 655 bp and the open reading frame of the cDNA encoded a 71 amino acid peptide. Ch-penaeidin contained a putative NH2-terminal signal sequence (1-19) followed by a mature peptide (20-71). The sequence identity with other penaeidins from Litopenaeus vannamei and Litopenaeus setiferus is between 48% and 71%. The signal sequence of Ch-penaeidin is almost completely identical to that of other penaeidins, while differing relatively in the N-terminal domain of the mature peptide. Ch-penaeidin was designated as a novel member of class penaeidin 3 according to phylogenetic analysis. The mature peptide, with a predicted molecular weight of 5589.32 Da, and a pI of 9.77, has eight positively charged amino acids and no negatively charged amino acids. The expression and distribution of Ch-penaeidin in unchallenged shrimps were studied by RT-PCR, Northern blot and in situ hybridisation. The results showed that the Ch-penaeidin transcripts were detected in haemocytes (granular haemocytes), heart, gill, intestine, and subcuticular epithelia of the shrimp, and that Ch-penaeidin was constitutively expressed mainly in haemocytes.
authors.affiliation: School of Life Sciences, Shandong University, Jinan, China.
authors.forename: Cui-Jie
authors.initials: CJ
authors.lastname: Kang
authors.forename: Jin-Xing
authors.initials: JX
authors.lastname: Wang
authors.forename: Xiao-Fan
authors.initials: XF
authors.lastname: Zhao
authors.forename: Xiao-Mei
authors.initials: XM
authors.lastname: Yang
authors.forename: Hong-Lian
authors.initials: HL
authors.lastname: Shao
authors.forename: Jian-Hai
authors.initials: JH
authors.lastname: Xiang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D015152:Blotting, Northern; D017931:DNA Primers; D018076:DNA, Complementary / Q000235:genetics; D040461:Gene Components; D020869:Gene Expression Profiling; D006434:Hemocytes / Q000737:chemistry; D007113:Immunity, Innate / Q000235:genetics*; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D008970:Molecular Weight; D033561:Penaeidae / Q000235:genetics* / Q000276:immunology; D010802:Phylogeny; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D017385:Sequence Homology
chemical_list: D023181:Antimicrobial Cationic Peptides; D017931:DNA Primers; D018076:DNA, Complementary