title: Early Events in the Amyloid Formation of the A546T Mutant of Transforming Growth Factor β-Induced Protein in Corneal Dystrophies Compared to the Nonfibrillating R555W and R555Q Mutants.
abstract: The human transforming growth factor β-induced protein (TGFBIp) is involved in several types of corneal dystrophies where protein aggregation and amyloid fibril formation severely impair vision. Most disease-causing mutations are located in the last of four homologous fasciclin-1 (FAS1) domains of the protein, and it has been shown that when isolated, the fourth FAS1 domain (FAS1-4) mimics the behavior of full-length TGFBIp. In this study, we use molecular dynamics simulations and principal component analysis to study the wild-type FAS1-4 domain along with three disease-causing mutations (R555W, R555Q, and A546T) to decipher any internal difference in dynamical properties of the domains that may explain their varied stabilities and aggregation properties. In addition, we use a protein-protein docking method in combination with chemical cross-linking experiments and mass spectrometry of the cross-linked species to obtain information about interaction faces between identical FAS1-4 domains. The results show that the pathogenic mutations A546T and R555W affect the packing in the hydrophobic core of FAS1-4 in different directions. We further show that the FAS1-4 monomers associate using their β-rich regions, consistent with peptides observed to be part of the amyloid fibril core in lattice corneal dystrophy patients.
authors: Center for Insoluble Protein Structures (inSPIN) and Interdisciplinary Nanoscience Center (iNANO), Aarhus University , Aarhus, Denmark.|Department of Chemistry, Aarhus University , Aarhus, Denmark.
authors: Heidi
authors: H
authors: Koldsø
authors: Center for Insoluble Protein Structures (inSPIN) and Interdisciplinary Nanoscience Center (iNANO), Aarhus University , Aarhus, Denmark.|Department of Chemistry, Aarhus University , Aarhus, Denmark.
authors: Ole Juul
authors: OJ
authors: Andersen
authors: Center for Insoluble Protein Structures (inSPIN) and Interdisciplinary Nanoscience Center (iNANO), Aarhus University , Aarhus, Denmark.|Department of Molecular Biology and Genetics, Aarhus University , Aarhus, Denmark.
authors: Camilla Lund
authors: CL
authors: Nikolajsen
authors: Center for Insoluble Protein Structures (inSPIN) and Interdisciplinary Nanoscience Center (iNANO), Aarhus University , Aarhus, Denmark.|Department of Molecular Biology and Genetics, Aarhus University , Aarhus, Denmark.
authors: Carsten
authors: C
authors: Scavenius
authors: Center for Insoluble Protein Structures (inSPIN) and Interdisciplinary Nanoscience Center (iNANO), Aarhus University , Aarhus, Denmark.|Department of Molecular Biology and Genetics, Aarhus University , Aarhus, Denmark.
authors: Charlotte S
authors: CS
authors: Sørensen
authors: Center for Insoluble Protein Structures (inSPIN) and Interdisciplinary Nanoscience Center (iNANO), Aarhus University , Aarhus, Denmark.|Department of Chemistry, Aarhus University , Aarhus, Denmark.
authors: Jarl
authors: J
authors: Underhaug
authors: Center for Insoluble Protein Structures (inSPIN) and Interdisciplinary Nanoscience Center (iNANO), Aarhus University , Aarhus, Denmark.|Department of Molecular Biology and Genetics, Aarhus University , Aarhus, Denmark.
authors: Kasper
authors: K
authors: Runager
authors: Center for Insoluble Protein Structures (inSPIN) and Interdisciplinary Nanoscience Center (iNANO), Aarhus University , Aarhus, Denmark.|Department of Chemistry, Aarhus University , Aarhus, Denmark.
authors: Niels Chr
authors: NC
authors: Nielsen
authors: Center for Insoluble Protein Structures (inSPIN) and Interdisciplinary Nanoscience Center (iNANO), Aarhus University , Aarhus, Denmark.|Department of Molecular Biology and Genetics, Aarhus University , Aarhus, Denmark.
authors: Jan J
authors: JJ
authors: Enghild
authors: Center for Insoluble Protein Structures (inSPIN) and Interdisciplinary Nanoscience Center (iNANO), Aarhus University , Aarhus, Denmark.|Department of Chemistry, Aarhus University , Aarhus, Denmark.
authors: Birgit
authors: B
authors: Schiøtt
mesh_terms: D000682:Amyloid / Q000737:chemistry* / Q000235:genetics; D002853:Chromatography, Liquid; D003198:Computer Simulation; D003317:Corneal Dystrophies, Hereditary / Q000235:genetics*; D003432:Cross-Linking Reagents / Q000737:chemistry; D016326:Extracellular Matrix Proteins / Q000737:chemistry* / Q000235:genetics; D057927:Hydrophobic and Hydrophilic Interactions; D056004:Molecular Dynamics Simulation; D009154:Mutation; D013388:Succinimides / Q000737:chemistry; D053719:Tandem Mass Spectrometry; D016212:Transforming Growth Factor beta / Q000737:chemistry* / Q000235:genetics; D000099222:betaIG-H3 Protein
chemical_list: D000682:Amyloid; D003432:Cross-Linking Reagents; D016326:Extracellular Matrix Proteins; D013388:Succinimides; D016212:Transforming Growth Factor beta; D000099222:betaIG-H3 Protein; C035760:bis(sulfosuccinimidyl)suberate