Identification of 1,1'-bi(4-anilino)naphthalene-5,5'-disulfonic acid binding sequences in alpha-crystallin

J Biol Chem. 1998 Jun 19;273(25):15474-8. doi: 10.1074/jbc.273.25.15474.

Abstract

The hydrophobic binding sites in alpha-crystallin were evaluated using fluorescent probes 1,1'-bi(4-anilino)naphthalenesulfonic acid (bis-ANS), 8-anilino-1-naphthalene sulfonate (ANS), and 1-azidonaphthalene 5-sulfonate (1,5-AZNS). The photolysis of bis-ANS-alpha-crystallin complex resulted in incorporation of the probe to both alphaA- and alphaB-subunits. Prior binding of denatured alcohol dehydrogenase to alpha-crystallin significantly decreased the photoincorporation of bis-ANS to alpha-crystallin. Localization of bis-ANS incorporated into alphaA-crystallin resulted in the identification of residues QSLFR and HFSPEDLTVK as the fluorophore binding regions. In alphaB-crystallin, sequences DRFSVNLNVK and VLGDVIEVHGK were found to be the bis-ANS binding regions. Of the bis-ANS binding sequences, HFSPEDLTVK of alphaA-crystallin and DRFSVNLNVK and VLGDVIEVHGK of alphaB-crystallin were earlier identified as part of the sequences involved in their interaction with target proteins during the molecular chaperone-like action. The hydrophobic probe, 1,5-AZNS, also interacted with both subunits of alpha-crystallin. Localization of 1,5-AZNS binding site in alphaB-crystallin lead to the identification of HFSPEEK sequence as the interacting site in this subunit of alpha-crystallin. Glycated alpha-crystallin displayed decreased ANS fluorescence and loss of chaperone-like function, suggesting the involvement of glycation site as well as ANS binding site in chaperone-like activity display.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Anilino Naphthalenesulfonates / metabolism*
  • Binding Sites
  • Chromatography, High Pressure Liquid
  • Cross-Linking Reagents / metabolism
  • Crystallins / chemistry
  • Crystallins / metabolism*
  • Fluorescent Dyes / metabolism*
  • Glycosylation
  • Molecular Sequence Data
  • Peptide Mapping
  • Photochemistry
  • Protein Denaturation

Substances

  • Anilino Naphthalenesulfonates
  • Cross-Linking Reagents
  • Crystallins
  • Fluorescent Dyes
  • 5,5'-bis(8-(phenylamino)-1-naphthalenesulfonate)