title: Der p 1 is the primary activator of Der p 3, Der p 6 and Der p 9 the proteolytic allergens produced by the house dust mite Dermatophagoides pteronyssinus.
abstract: BACKGROUND
  The enzymatic activity of the four proteases found in the house dust mite Dermatophagoides pteronyssinus is involved in the pathogenesis of allergy. Our aim was to elucidate the activation cascade of their corresponding precursor forms and particularly to highlight the interconnection between proteases during this cascade.
  
  
  METHODS
  The cleavage of the four peptides corresponding to the mite zymogen activation sites was studied on the basis of the Förster Resonance Energy Transfer method. The proDer p 6 zymogen was then produced in Pichia pastoris to elucidate its activation mechanism by mite proteases, especially Der p 1. The role of the propeptide in the inhibition of the enzymatic activity of Der p 6 was also examined. Finally, the Der p 1 and Der p 6 proteases were localised via immunolocalisation in D. pteronyssinus.
  
  
  RESULTS
  All peptides were specifically cleaved by Der p 1, such as proDer p 6. The propeptide of proDer p 6 inhibited the proteolytic activity of Der p 6, but once cleaved, it was degraded by the protease. The Der p 1 and Der p 6 proteases were both localised to the midgut of the mite.
  
  
  CONCLUSIONS
  Der p 1 in either its recombinant form or in the natural context of house dust mite extracts specifically cleaves all zymogens, thus establishing its role as a major activator of both mite cysteine and serine proteases.
  
  
  CONCLUSIONS
  This finding suggests that Der p 1 may be valuable target against mites.
authors.affiliation: Macromolécules Biologiques, Centre for Protein Engineering, University of Liège, 4000 Liège, Belgium.
authors.forename: Julie
authors.initials: J
authors.lastname: Herman
authors.affiliation: Unit of Cell and Tissue Biology, GIGA-Neurosciences, University of Liège, 4000 Liège, Belgium.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Thelen
authors.affiliation: Mass Spectrometry Laboratory, GIGA-R, Department of Chemistry, University of Liège, 4000 Liège, Belgium.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Smargiasso
authors.affiliation: Earth and Life Institute, Université catholique de Louvain, 1348 Louvain-la-Neuve, Belgium.
authors.forename: Anne-Catherine
authors.initials: AC
authors.lastname: Mailleux
authors.affiliation: Centre de Recherche du Cyclotron, University of Liège, 4000 Liège, Belgium.
authors.forename: André
authors.initials: A
authors.lastname: Luxen
authors.affiliation: Unit of Cell and Tissue Biology, GIGA-Neurosciences, University of Liège, 4000 Liège, Belgium.
authors.forename: Marie
authors.initials: M
authors.lastname: Cloes
authors.affiliation: Mass Spectrometry Laboratory, GIGA-R, Department of Chemistry, University of Liège, 4000 Liège, Belgium.
authors.forename: Edwin
authors.initials: E
authors.lastname: De Pauw
authors.affiliation: Laboratory of Retrovirology, CRP-Santé, 1526 Luxembourg, Luxembourg.
authors.forename: Andy
authors.initials: A
authors.lastname: Chevigné
authors.affiliation: Macromolécules Biologiques, Centre for Protein Engineering, University of Liège, 4000 Liège, Belgium. Electronic address: mgalleni@ulg.ac.be.
authors.forename: Moreno
authors.initials: M
authors.lastname: Galleni
authors.affiliation: Macromolécules Biologiques, Centre for Protein Engineering, University of Liège, 4000 Liège, Belgium; Laboratory of Retrovirology, CRP-Santé, 1526 Luxembourg, Luxembourg.
authors.forename: Marie-Eve
authors.initials: ME
authors.lastname: Dumez
mesh_terms: D000485:Allergens / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D039741:Antigens, Dermatophagoides / Q000032:analysis / Q000378:metabolism*; D060829:Arthropod Proteins / Q000032:analysis / Q000378:metabolism*; D003546:Cysteine Endopeptidases / Q000032:analysis / Q000378:metabolism*; D040002:Dermatophagoides pteronyssinus / Q000276:immunology*; D004789:Enzyme Activation; D004792:Enzyme Precursors / Q000378:metabolism; D008969:Molecular Sequence Data; D059748:Proteolysis; D011994:Recombinant Proteins / Q000378:metabolism; D012697:Serine Endopeptidases / Q000032:analysis / Q000378:metabolism*
chemical_list: D000485:Allergens; D039741:Antigens, Dermatophagoides; D060829:Arthropod Proteins; D004792:Enzyme Precursors; D011994:Recombinant Proteins; C451165:Dermatophagoides pteronyssinus antigen p 3; C451183:Dermatophagoides pteronyssinus antigen p 6; D012697:Serine Endopeptidases; D003546:Cysteine Endopeptidases; C451162:Dermatophagoides pteronyssinus antigen p 1
keywords: 4′,6-DiAmidino-2-PhenylIndole; 7-amido-4-methylcoumarin; AMC; AMg; DAPI; Dermatophagoides pteronyssinus; Digestion; E-64; FP; FRET; Förster Resonance Energy Transfer; HDM(e); Hg; Mite allergen; PMg; Protease; SBTI; anterior midgut; faecal pellet; hindgut; house dust mite (extracts); l-trans-epoxysuccinyl-leucylamido (4-guanidino) butane; nDer p 6; natural Der p 6; pDp6; posterior midgut; proDer p 6; rDer p 1; rDer p 6; recombinant Der p 1; recombinant Der p 6; soybean trypsin inhibitor