Mre11 is a nuclear protein involved in homologous recombination, telomere length maintenance, and DNA double-strand break repair. By itself, MRE11 functions in the nucleus as a 3′ to 5′ exonuclease and endonuclease, facilitating DNA end processing to promote repair and maintain genomic stability. Nuclear localization ensures rapid response to DNA damage, preventing potential mutations and neoplastic transformations. MRE11 participates in telomere maintenance, highlighting significance in cellular health and longevity. In conjunction with a DNA ligase, Mre11 protein promotes the joining of noncomplementary ends in vitro using short homologies near the ends of the DNA fragments.