MRE11 is a crucial protein in DNA repair processes, part of the MRE11-RAD50-NBS1 (MRN) complex. It possesses exonuclease and endonuclease activities, essential for homologous recombination repair and non-homologous end joining. MRE11 is primarily located in the nucleus, involved in the sensing and signaling of DNA damage. The protein is expressed in various cell types, particularly prominent in actively dividing cells. Mutations in the MRE11 gene are associated with the development of several cancers, notably breast and ovarian cancer.