A glimpse into the hidden world of the flexible C-terminal protein binding domains of human RAD52

J Struct Biol. 2024 Sep;216(3):108115. doi: 10.1016/j.jsb.2024.108115. Epub 2024 Aug 6.

Abstract

Human RAD52 protein binds DNA and is involved in genomic stability maintenance and several forms of DNA repair, including homologous recombination and single-strand annealing. Despite its importance, there are very few structural details about the variability of the RAD52 ring size and the RAD52 C-terminal protein-protein interaction domains. Even recent attempts to employ cryogenic electron microscopy (cryoEM) methods on full-length yeast and human RAD52 do not reveal interpretable structures for the C-terminal half that contains the replication protein A (RPA) and RAD51 binding domains. In this study, we employed the monodisperse purification of two RAD52 deletion constructs and small angle X-ray scattering (SAXS) to construct a structural model that includes RAD52's RPA binding domain. This model is of interest to DNA repair specialists as well as for drug development against HR-deficient cancers.

Keywords: Cancer therapeutics; Homologous recombination; RAD51; RAD52; Replication Protein A; Single strand annealing; Small angle X-ray scattering.

MeSH terms

  • DNA Repair
  • Humans
  • Models, Molecular
  • Protein Binding*
  • Protein Domains
  • Rad51 Recombinase / chemistry
  • Rad51 Recombinase / genetics
  • Rad51 Recombinase / metabolism
  • Rad52 DNA Repair and Recombination Protein* / chemistry
  • Rad52 DNA Repair and Recombination Protein* / genetics
  • Rad52 DNA Repair and Recombination Protein* / metabolism
  • Replication Protein A* / chemistry
  • Replication Protein A* / genetics
  • Replication Protein A* / metabolism
  • Scattering, Small Angle*
  • X-Ray Diffraction / methods

Substances

  • Rad52 DNA Repair and Recombination Protein
  • RAD52 protein, human
  • Replication Protein A
  • Rad51 Recombinase