title: In vivo activity and the transcriptional regulatory mechanism of the antimicrobial peptide SpHyastatin in Scylla paramamosain.
abstract: A new gene homologous to the reported antimicrobial peptide (AMP) hyastatin from Hyas araneus was screened in the SSH library constructed from the hemocytes of Scylla paramamosain, and named SpHyastatin. In vivo study showed that SpHyastatin was predominantly expressed in hemocytes of S. paramamosain. With the challenge of either Vibrio parahaemolyticus or lipopolysaccharide (LPS), SpHyastatin showed a positive response, meaning that it was probably involved in the immune reaction against bacterial infection in vivo. A distinctive feature of SpHyastatin in comparison with six other known AMPs tested was that SpHyastatin could maintain a higher transcription level from megalopas to the adult crab, indicating a potential consistent resistance against pathogens conferred by this peptide existing in the blood circulation of crabs. RNA interference assay was performed to inhibit SpHyastatin transcription in vivo and the result demonstrated that silencing SpHyastatin mRNA transcripts could decrease the survival rate of crabs challenged with V. parahaemolyticus. To further understand the molecular mechanisms that regulate SpHyastatin expression, a 576 bp 5'-flanking sequence of SpHyastatin was obtained using genome walking. Here, we focused our experiments on investigating the roles of the putative NF-κB binding site in LPS-mediated transcriptional regulation of the SpHyastatin gene using endothelial progenitor cells and Hela cells. Luciferase reporter analyses demonstrated that the putative NF-κB element acted as a positive regulatory element and was essential for the induction of SpHyastatin promoter by LPS. These results should shed light on the in vivo functional property and the molecular mechanism of regulation for the crab AMP SpHyastatin.
authors.affiliation: State Key Laboratory of Marine Environmental Science, College of Ocean & Earth Science, Xiamen University, Xiamen, Fujian, 361005, PR China.
authors.forename: Zhong-Guo
authors.initials: ZG
authors.lastname: Shan
authors.affiliation: State Key Laboratory of Marine Environmental Science, College of Ocean & Earth Science, Xiamen University, Xiamen, Fujian, 361005, PR China.
authors.forename: Ke-Xin
authors.initials: KX
authors.lastname: Zhu
authors.affiliation: State Key Laboratory of Marine Environmental Science, College of Ocean & Earth Science, Xiamen University, Xiamen, Fujian, 361005, PR China; Fujian Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources, Xiamen University, Xiamen, Fujian, 361005, PR China; State-Province Joint Engineering Laboratory of Marine Bioproducts and Technology, Xiamen University, Xiamen, Fujian, 361005, PR China.
authors.forename: Fang-Yi
authors.initials: FY
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Marine Environmental Science, College of Ocean & Earth Science, Xiamen University, Xiamen, Fujian, 361005, PR China.
authors.forename: Jie
authors.initials: J
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Marine Environmental Science, College of Ocean & Earth Science, Xiamen University, Xiamen, Fujian, 361005, PR China.
authors.forename: Bei
authors.initials: B
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Marine Environmental Science, College of Ocean & Earth Science, Xiamen University, Xiamen, Fujian, 361005, PR China.
authors.forename: Kun
authors.initials: K
authors.lastname: Qiao
authors.affiliation: State Key Laboratory of Marine Environmental Science, College of Ocean & Earth Science, Xiamen University, Xiamen, Fujian, 361005, PR China; Fujian Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources, Xiamen University, Xiamen, Fujian, 361005, PR China; State-Province Joint Engineering Laboratory of Marine Bioproducts and Technology, Xiamen University, Xiamen, Fujian, 361005, PR China.
authors.forename: Hui
authors.initials: H
authors.lastname: Peng
authors.affiliation: State Key Laboratory of Marine Environmental Science, College of Ocean & Earth Science, Xiamen University, Xiamen, Fujian, 361005, PR China; Fujian Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources, Xiamen University, Xiamen, Fujian, 361005, PR China; State-Province Joint Engineering Laboratory of Marine Bioproducts and Technology, Xiamen University, Xiamen, Fujian, 361005, PR China. Electronic address: wkjian@xmu.edu.cn.
authors.forename: Ke-Jian
authors.initials: KJ
authors.lastname: Wang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000737:chemistry / Q000235:genetics* / Q000276:immunology*; D060829:Arthropod Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology; D003386:Brachyura / Q000235:genetics* / Q000276:immunology* / Q000382:microbiology; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000737:chemistry; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects / Q000276:immunology; D008070:Lipopolysaccharides / Q000494:pharmacology; D008297:Male; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D014736:Vibrio parahaemolyticus / Q000502:physiology*
chemical_list: D023181:Antimicrobial Cationic Peptides; D060829:Arthropod Proteins; D008070:Lipopolysaccharides; D012333:RNA, Messenger
keywords: Antimicrobial peptide; Invertebrate immunity; Scylla paramamosain; SpHyastatin; Transcriptional regulation