Alignment of fibrillin molecules in elastic microfibrils is defined by transglutaminase-derived cross-links

Biochemistry. 1997 Dec 16;36(50):15841-7. doi: 10.1021/bi971036f.

Abstract

Microfibrils were extracted from human amnion in the form of a beaded filament and analyzed for the presence of transglutaminase-derived cross-links using acrylonitrile derivatization. The cross-link structure was isolated from protease hydrolysates of beaded filaments and identified as a phenylthiocarbamyl amino acid derivative by comparison to a standard. Acid hydrolysis of the isolated cross-link gave the expected lysine and glutamic acid in a 1:1 ratio. The beaded filaments were also treated with trypsin to produce a fraction that contained the bead structure and a fraction containing fragments of the interbead filaments. Cross-links were detected in the interbead filaments but not in the beads. A large tryptic peptide that contained a cross-link was isolated and sequenced. The two amino acid sequences obtained identified both of the cross-linked molecules as fibrillin-1 and enabled the approximate localization of the cross-link sites within the molecule. The locations of cross-link sites on two adjacent molecules fixed the relative positions of fibrillin monomers within the microfibrils, providing insight into the spatial organization of fibrillin within the elastic microfibrils.

MeSH terms

  • Acrylonitrile
  • Actin Cytoskeleton / chemistry*
  • Actin Cytoskeleton / ultrastructure
  • Amino Acid Sequence
  • Amino Acids / analysis
  • Amnion / chemistry
  • Chromatography, High Pressure Liquid
  • Cross-Linking Reagents
  • Electrophoresis, Capillary
  • Fibrillin-1
  • Fibrillins
  • Glutamic Acid / analysis
  • Humans
  • Lysine / analysis
  • Microfilament Proteins / chemistry*
  • Microfilament Proteins / isolation & purification
  • Microfilament Proteins / ultrastructure
  • Microscopy, Electron
  • Models, Molecular
  • Molecular Sequence Data
  • Peptide Fragments / chemistry
  • Sequence Analysis
  • Transglutaminases / metabolism*
  • Trypsin / metabolism

Substances

  • Amino Acids
  • Cross-Linking Reagents
  • FBN1 protein, human
  • Fibrillin-1
  • Fibrillins
  • Microfilament Proteins
  • Peptide Fragments
  • Glutamic Acid
  • Transglutaminases
  • Trypsin
  • Lysine
  • Acrylonitrile