Human Rad50/Mre11 is a flexible complex that can tether DNA ends

Mol Cell. 2001 Nov;8(5):1129-35. doi: 10.1016/s1097-2765(01)00381-1.


The human Rad50 protein, classified as a structural maintenance of chromosomes (SMC) family member, is complexed with Mre11 (R/M) and has important functions in at least two distinct double-strand break repair pathways. To find out what the common function of R/M in these pathways might be, we investigated its architecture. Scanning force microscopy showed that the complex architecture is distinct from the described SMC family members. R/M consisted of two highly flexible intramolecular coiled coils emanating from a central globular DNA binding domain. DNA end-bound R/M oligomers could tether linear DNA molecules. These observations suggest that a unified role for R/M in multiple aspects of DNA repair and chromosome metabolism is to provide a flexible, possibly dynamic, link between DNA ends.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • DNA / metabolism*
  • DNA Repair
  • DNA-Binding Proteins / chemistry*
  • DNA-Binding Proteins / metabolism
  • Fungal Proteins / chemistry*
  • Fungal Proteins / metabolism
  • Humans
  • MRE11 Homologue Protein
  • Macromolecular Substances
  • Microscopy, Atomic Force
  • Protein Structure, Tertiary
  • Saccharomyces cerevisiae Proteins*


  • DNA-Binding Proteins
  • Fungal Proteins
  • MRE11 protein, human
  • Macromolecular Substances
  • RAD50 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins
  • DNA
  • MRE11 Homologue Protein