title: Feeding truncated heat shock protein 70s protect Artemia franciscana against virulent Vibrio campbellii challenge.
abstract: The 70 kDa heat shock proteins (Hsp70s) are highly conserved in evolution, leading to striking similarities in structure and composition between eukaryotic Hsp70s and their homologs in prokaryotes. The eukaryotic Hsp70 like the DnaK (Escherichia coli equivalent Hsp70) protein, consist of three functionally distinct domains: an N-terminal 44-kDa ATPase portion, an 18-kDa peptide-binding domain and a C-terminal 10-kDa fragment. Previously, the amino acid sequence of eukaryotic (the brine shrimp Artemia franciscana) Hsp70 and DnaK proteins were shown to share a high degree of homology, particularly in the peptide-binding domain (59.6%, the putative innate immunity-activating portion) compared to the N-terminal ATPase (48.8%) and the C-terminal lid domains (19.4%). Next to this remarkable conservation, these proteins have been shown to generate protective immunity in Artemia against pathogenic Vibrio campbellii. This study, aimed to unravel the Vibrio-protective domain of Hsp70s in vivo, demonstrated that gnotobiotically cultured Artemia fed with recombinant C-terminal fragment (containing the conserved peptide binding domain) of Artemia Hsp70 or DnaK protein were well protected against subsequent Vibrio challenge. In addition, the prophenoloxidase (proPO) system, at both mRNA and protein activity levels, was also markedly induced by these truncated proteins, suggesting epitope(s) responsible for priming the proPO system and presumably other immune-related genes, consequently boosting Artemia survival upon challenge with V. campbellii, might be located within this conserved region of the peptide binding domain.
authors.affiliation: Laboratory of Aquaculture & Artemia Reference Center, Faculty of Bioscience Engineering, Ghent University, Gent 9000, Belgium. baruahkartik4@rediffmail.com
authors.forename: Kartik
authors.initials: K
authors.lastname: Baruah
authors.forename: Parisa
authors.initials: P
authors.lastname: Norouzitallab
authors.forename: Li
authors.initials: L
authors.lastname: Shihao
authors.forename: Patrick
authors.initials: P
authors.lastname: Sorgeloos
authors.forename: Peter
authors.initials: P
authors.lastname: Bossier
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001156:Artemia / Q000276:immunology* / Q000382:microbiology; D060829:Arthropod Proteins / Q000235:genetics / Q000276:immunology*; D015153:Blotting, Western; D004156:Catechol Oxidase / Q000378:metabolism; D003001:Cloning, Molecular; D004792:Enzyme Precursors / Q000378:metabolism; D004926:Escherichia coli; D029968:Escherichia coli Proteins / Q000235:genetics / Q000276:immunology; D005856:Germ-Free Life; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics / Q000276:immunology*; D007113:Immunity, Innate; D012333:RNA, Messenger / Q000235:genetics; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology; D020539:Sequence Analysis, Protein; D014733:Vibrio / Q000276:immunology*
chemical_list: D060829:Arthropod Proteins; D004792:Enzyme Precursors; D029968:Escherichia coli Proteins; D018840:HSP70 Heat-Shock Proteins; D012333:RNA, Messenger; D011994:Recombinant Proteins; C038451:pro-phenoloxidase; D004156:Catechol Oxidase; C063842:dnaK protein, E coli