title: Distinct regulation patterns of the two prophenoloxidase activating enzymes corresponding to bacteria challenge and their compensatory over expression feature in white shrimp (Litopenaeus vannamei).
abstract: Prophenoloxidase activating enzyme 2 (PPAE2), which belongs to the second PPAE family of prawns, was isolated from white shrimp Litopenaeus vannamei. The currently identified lvPPAE2 and lvPPAE1 from our former report were taken as model candidates to analyze the relationship of the two shrimp PPAE families as well as the regulation mechanism of shrimp PPAEs. The tissue expression of lvPPAE2 was more ubiquitous than lvPPAE1. The mRNA abundance of lvPPAE2 was about 10 percent of lvPPAE1 in co-existed tissues. When challenged with Vibrio harveyi. LvPPAE2 showed a distinct transcriptional regulation pattern compared to lvPPAE1. Silence of lvPPAE2 significantly increased shrimp's susceptibility to V. harveyi, suggesting the lvPPAE2 plays essential role in shrimp host defense. A novel PPAE specific compensatory over expression feature was found in the two lvPPAEs. Single gene specific silence of lvPPAE1 and lvPPAE2 resulted in a significant difference in reduction of hemolymph PO activity. Double silence of the two lvPPAEs failed to cause a further reduction on PO activity or shrimp mortality to bacteria, despite that double silence sufficiently suppressed both of the two lvPPAEs. Our findings suggest both lvPPAEs contribute to shrimp melanization cascade and host defense against bacteria. Distinct regulation pattern corresponding to the same pathogen invasion suggests the two lvPPAEs are actually under different regulation ways. A novel PPAE specific compensatory over expression mechanism found in our study offered us a clue in understanding the robustness of shrimp innate immunity and network of crustacean proPO activating system.
authors.affiliation: National Fisheries Research & Development Institute, Ulwang-dong 707, Jung-gu, Incheon 400-420, South Korea. Electronic address: pangzsr@gmail.com.
authors.forename: Zhenguo
authors.initials: Z
authors.lastname: Pang
authors.affiliation: National Fisheries Research & Development Institute, Ulwang-dong 707, Jung-gu, Incheon 400-420, South Korea. Electronic address: agemang@nfrdi.go.kr.
authors.forename: Su-Kyoung
authors.initials: SK
authors.lastname: Kim
authors.affiliation: National Fisheries Research & Development Institute, Ulwang-dong 707, Jung-gu, Incheon 400-420, South Korea. Electronic address: yujiaping1@yahoo.com.cn.
authors.forename: Jiaping
authors.initials: J
authors.lastname: Yu
authors.affiliation: National Fisheries Research & Development Institute, Ulwang-dong 707, Jung-gu, Incheon 400-420, South Korea. Electronic address: jangik@korea.kr.
authors.forename: In-Kwon
authors.initials: IK
authors.lastname: Jang
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001483:Base Sequence; D017931:DNA Primers / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics; D020869:Gene Expression Profiling; D015971:Gene Expression Regulation, Enzymologic / Q000276:immunology*; D007113:Immunity, Innate / Q000235:genetics / Q000276:immunology*; D008969:Molecular Sequence Data; D033561:Penaeidae / Q000201:enzymology* / Q000276:immunology* / Q000382:microbiology; D012333:RNA, Messenger / Q000378:metabolism; D017422:Sequence Analysis, DNA; D012697:Serine Endopeptidases / Q000235:genetics* / Q000276:immunology* / Q000378:metabolism; D014733:Vibrio / Q000276:immunology*
chemical_list: D017931:DNA Primers; D018076:DNA, Complementary; D012333:RNA, Messenger; D012697:Serine Endopeptidases; C022435:prephenoloxidase-activating enzyme
keywords: Compensatory over-expression; Gene silence; Innate immunity; Litopenaeus vannamei; Prophenoloxidase activating