title: Alpha-2-macroglobulin is a modulator of prophenoloxidase system in pacific white shrimp Litopenaeus vannamai.
abstract: The shrimp multifunctional protein alpha-2-macroglobulin (A2M) is abundantly expressed in plasma, highly up-regulated upon microbial infection and involved in several immune pathways such as blood clotting system, phagocytosis and melanization. Herein, the function of LvA2M from Litopenaeus vannamei on the prophenoloxidase (proPO) system is reported. The recombinant (r)LvA2M produced strongly and specifically inhibited trypsin and the PO activity in shrimp plasma in a dose-dependent manner. Silencing of LvA2M led to an increase in the PO activity in shrimp plasma although the expression of proPO-associated genes, proPO-activating enzyme (PPAE) and prophenoloxidase (proPO) but not the proPO-activating factor (PPAF) was down-regulated. In Vibrio parahaemolyticus AHPND-infected shrimp, the LvA2M activity was suppressed in an early phase of infection while the PO activity was increased. Thus, the proPO-activating system was regulated by the LvA2M.
authors.affiliation: Department of Chemistry, Faculty of Science, Srinakharinwirot University, 114 Sukhumvit 23 Road, Bangkok 10110, Thailand. Electronic address: sirikwanp@g.swu.ac.th.
authors.forename: Sirikwan
authors.initials: S
authors.lastname: Ponprateep
authors.affiliation: Applied Analytical Chemistry Research Unit, Department of Chemistry, Faculty of Science, King Mongkut's Institute of Technology Ladkrabang, Chalongkrung Road, Bangkok 10520, Thailand.
authors.forename: Tipachai
authors.initials: T
authors.lastname: Vatanavicharn
authors.affiliation: Institute of Bioinformatics and Biosignal Transduction, College of Bioscience and Biotechnology, National Cheng Kung University, Tainan 701, Taiwan.
authors.forename: Chu Fang
authors.initials: CF
authors.lastname: Lo
authors.affiliation: Center of Excellence for Molecular Biology and Genomics of Shrimp, Department of Biochemistry, Faculty of Science, Chulalongkorn University, Phyathai Road, Bangkok 10330, Thailand.
authors.forename: Anchalee
authors.initials: A
authors.lastname: Tassanakajon
authors.affiliation: Center of Excellence for Molecular Biology and Genomics of Shrimp, Department of Biochemistry, Faculty of Science, Chulalongkorn University, Phyathai Road, Bangkok 10330, Thailand. Electronic address: kpvr2@yahoo.com.
authors.forename: Vichien
authors.initials: V
authors.lastname: Rimphanitchayakit
mesh_terms: D000818:Animals; D060829:Arthropod Proteins / Q000235:genetics* / Q000378:metabolism; D004156:Catechol Oxidase / Q000235:genetics / Q000378:metabolism; D004792:Enzyme Precursors / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D055785:Gene Knockdown Techniques; D007113:Immunity, Innate; D033561:Penaeidae / Q000235:genetics* / Q000276:immunology / Q000382:microbiology; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D057057:Serine Proteases / Q000235:genetics / Q000378:metabolism; D014736:Vibrio parahaemolyticus / Q000502:physiology*; D000511:alpha-Macroglobulins / Q000235:genetics* / Q000378:metabolism
chemical_list: D060829:Arthropod Proteins; D004792:Enzyme Precursors; D011994:Recombinant Proteins; D000511:alpha-Macroglobulins; C038451:pro-phenoloxidase; D004156:Catechol Oxidase; D057057:Serine Proteases
keywords: Alpha-2-macroglobulin; Litopenaeus vannamei; Prophenoloxidase system; Proteinase inhibitor; Vibrio parahaemolyticus AHPND