Dimerization of human recombinant resistin involves covalent and noncovalent interactions

Biochem Biophys Res Commun. 2004 Jan 16;313(3):642-6. doi: 10.1016/j.bbrc.2003.11.156.

Abstract

Resistin, an adipocyte secreted cysteine rich hormone has been implicated as molecular link between obesity and type 2 diabetes in a murine model. Although, at the protein level mouse and human resistin show remarkable similarities with respect to conserved cysteine residues, the physiological role of human resistin is not yet clear. In the present study we describe the purification and refolding of human recombinant resistin using two different refolding processes. Gel filtration analysis of protein refolded by both the methods revealed that human recombinant resistin, like mouse resistin, has a tendency to form dimers. Interestingly, dimerization of resistin appears to be mediated by both covalent (disulfide bond mediated) and non-covalent interactions as seen on reducing and non-reducing SDS-PAGE. Circular dichroism spectral analysis revealed that human resistin peptide backbone is a mixture of alpha-helical and beta-sheet conformation with significant amounts of unordered structure, similar to the mouse resistin. It is likely that the first cysteine (Cyst22) of human resistin, which is equivalent to mouse Cyst26, may be involved in stabilizing the dimers through covalent interaction.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adipocytes / metabolism
  • Amino Acid Sequence
  • Animals
  • Chromatography, Gel
  • Circular Dichroism
  • Cloning, Molecular
  • Cysteine / chemistry
  • Diabetes Mellitus, Type 2 / genetics
  • Dimerization
  • Disulfides
  • Electrophoresis, Polyacrylamide Gel
  • Escherichia coli / metabolism
  • Hormones, Ectopic / chemistry*
  • Hormones, Ectopic / genetics
  • Hormones, Ectopic / metabolism
  • Humans
  • Insulin Resistance
  • Mice
  • Molecular Sequence Data
  • Obesity / metabolism
  • Peptides / chemistry
  • Protein Binding
  • Protein Conformation
  • Protein Structure, Secondary
  • Recombinant Proteins / chemistry*
  • Resistin
  • Sequence Homology, Amino Acid

Substances

  • Disulfides
  • Hormones, Ectopic
  • Peptides
  • RETN protein, human
  • Recombinant Proteins
  • Resistin
  • Retn protein, mouse
  • Cysteine