title: Anti-amyloidogenic property of human gastrokine 1.
abstract: Gastrokine 1 (GKN1) is a stomach-specific protein expressed in normal gastric tissue but absent in gastric cancer. GKN1 plays a major role in maintaining gastric mucosa integrity and is characterized by the presence of a BRICHOS domain consisting of about 100 amino acids also found in several unrelated proteins associated with major human diseases like BRI2, related to familial British and Danish dementia and surfactant protein C (SP-C), associated with respiratory distress syndrome. It was reported that recombinant BRICHOS domains from BRI2 and SP-C precursor (proSP-C) prevent fibrils formation of amyloid-beta peptide (Aβ), that is the major component of extracellular amyloid deposits in Alzheimer's disease. Here we investigated on the interaction between human recombinant GKN1 (rGKN1) and Aβ peptide (1-40) that derives from the partial hydrolysis of the amyloid precursor protein (APP). GKN1 prevented amyloid aggregation and fibrils formation by inhibiting Aβ(1-40) polymerization, as evaluated by SDS-PAGE, thioflavin-T binding assay and gel filtration experiments. Mass spectrometry showed the formation of a prevailing 1:1 complex between GKN1 and Aβ(1-40). SPR analysis of GKN1/Aβ interaction led to calculate a dissociation constant (KD) of 34 μM. Besides its interaction with Aβ(1-40), GKN1 showed also to interact with APP as evaluated by confocal microscopy and Ni-NTA pull-down. Data strongly suggest that GKN1 has anti-amyloidogenic properties thus functioning as a chaperone directed against unfolded segments and with the ability to recognize amyloidogenic polypeptides and prevent their aggregation.
authors.affiliation: Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II, Naples, Italy.
authors.forename: Filomena
authors.initials: F
authors.lastname: Altieri
authors.affiliation: Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II, Naples, Italy.
authors.forename: Chiara Stella
authors.initials: CS
authors.lastname: Di Stadio
authors.affiliation: Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, Second University of Naples, Caserta, Italy; Institute of Biostructures and Bioimaging-IBB, CNR, Naples, Italy.
authors.forename: Valeria
authors.initials: V
authors.lastname: Severino
authors.affiliation: Institute of Biostructures and Bioimaging-IBB, CNR, Naples, Italy.
authors.forename: Annamaria
authors.initials: A
authors.lastname: Sandomenico
authors.affiliation: Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II, Naples, Italy; CEINGE, Advanced Biotechnology Scarl, Via Gaetano Salvatore 486, I-80145 Naples, Italy.
authors.forename: Giuseppina
authors.initials: G
authors.lastname: Minopoli
authors.affiliation: Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II, Naples, Italy.
authors.forename: Giuseppina
authors.initials: G
authors.lastname: Miselli
authors.affiliation: Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, Second University of Naples, Caserta, Italy.
authors.forename: Antimo
authors.initials: A
authors.lastname: Di Maro
authors.affiliation: Institute of Biostructures and Bioimaging-IBB, CNR, Naples, Italy.
authors.forename: Menotti
authors.initials: M
authors.lastname: Ruvo
authors.affiliation: Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, Second University of Naples, Caserta, Italy; IRCCS Multimedica, Milan, Italy.
authors.forename: Angela
authors.initials: A
authors.lastname: Chambery
authors.affiliation: Laboratory of Biotechnology, Department of Anesthesia, Surgical and Emergency Sciences, Second University of Naples, Via Costantinopoli 16, I-80138 Naples, Italy.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Quagliariello
authors.affiliation: Department of Motor Sciences and Wellness, University of Parthenope, Naples, Italy.
authors.forename: Mariorosario
authors.initials: M
authors.lastname: Masullo
authors.affiliation: Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II, Naples, Italy. Electronic address: emilia.rippa@unina.it.
authors.forename: Emilia
authors.initials: E
authors.lastname: Rippa
authors.affiliation: Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II, Naples, Italy; CEINGE, Advanced Biotechnology Scarl, Via Gaetano Salvatore 486, I-80145 Naples, Italy. Electronic address: paolo.arcari@unina.it.
authors.forename: Paolo
authors.initials: P
authors.lastname: Arcari
mesh_terms: D000595:Amino Acid Sequence; D000682:Amyloid / Q000737:chemistry / Q000378:metabolism*; D016229:Amyloid beta-Peptides / Q000737:chemistry / Q000378:metabolism*; D016564:Amyloid beta-Protein Precursor / Q000378:metabolism; D045744:Cell Line, Tumor; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D018613:Microscopy, Confocal; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry / Q000378:metabolism*; D036361:Peptide Hormones / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D066329:Protein Aggregates / Q000187:drug effects; D011485:Protein Binding; D011994:Recombinant Proteins / Q000378:metabolism / Q000494:pharmacology; D017386:Sequence Homology, Amino Acid; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D000682:Amyloid; D016229:Amyloid beta-Peptides; D016564:Amyloid beta-Protein Precursor; C477000:GKN1 protein, human; D010446:Peptide Fragments; D036361:Peptide Hormones; D066329:Protein Aggregates; D011994:Recombinant Proteins; C078592:amyloid beta-protein (1-40)
keywords: APP; Amyloidogenesis; Aβ peptide; BRICHOS domain; Gastric cancer; Gastrokine 1