DNA-binding induced conformational change of c-Myb R2R3 analyzed using diffracted X-ray tracking

Biochem Biophys Res Commun. 2018 Sep 3;503(1):338-343. doi: 10.1016/j.bbrc.2018.06.025. Epub 2018 Jun 19.

Abstract

Previous structural analyses have shown that R2R3, the minimum unit of the DNA-binding domain of the transcriptional factor c-Myb, is largely flexible in solution, and changes to a more rigid structure upon DNA binding. In this study, we evaluated the structural dynamics using the diffracted X-ray tracking method, in correlation with DNA-binding abilities under different salt conditions, and compared them with the previous results. The resultant curve of the mean square angular displacements (MSD) clearly showed that the flexibility of R2R3 was decreased upon DNA binding, and the DNA-binding energies determined using the angular diffusion coefficients were in good agreement with those determined using isothermal titration calorimetry. The results of the MSD curves also indicate that the translational length reduces by approximately half upon DNA binding.

Keywords: Binding thermodynamics; DNA-Binding protein; Protein fluctuation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Binding Sites
  • Calorimetry
  • DNA / metabolism*
  • Mutation
  • Protein Binding
  • Protein Conformation
  • Protein Domains
  • Proto-Oncogene Proteins c-myb / chemistry
  • Proto-Oncogene Proteins c-myb / genetics
  • Proto-Oncogene Proteins c-myb / metabolism*
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism
  • Thermodynamics
  • X-Ray Diffraction

Substances

  • Proto-Oncogene Proteins c-myb
  • Recombinant Proteins
  • DNA