Encyclopedia of Signaling Molecules

2018 Edition
| Editors: Sangdun Choi

EXO1 (Exonuclease 1)

  • Lene Juel RasmussenEmail author
  • Guido KeijzersEmail author
Reference work entry
DOI: https://doi.org/10.1007/978-3-319-67199-4_101686


Historical Background

Exonuclease 1 (EXO1) was first identified in Schizosaccharomyces pombe (Szankasi and Smith 1995) and belongs to the Rad2/XPG family, which is conserved in its nuclease domain through species (Szankasi and Smith 1995; Wilson et al. 1998). The nuclease domain is located at the NH2-terminus and contains two subdomains the N-domain (N) and the internal (I) domain separated by a spacer region (Fig. 1). The EXO1 gene product exerts a 5′ → 3′ exonuclease and 5′ flap endonuclease activity (Lee and Wilson 1999; Keijzers et al. 2015). In addition, the EXO1 protein exhibits 5′ → 3′ intrinsic RNase H activity (Qiu et al. 1999). EXO1 has high affinity for processing double stranded DNA breaks (DSB), nicks, gaps, and pseudo-Y structures and can resolve double Holliday junctions. EXO1 is expressed at low level, independently of the cell cycle progression or proliferative status of the human cell (El-Shemerly et al. 2005). However,...
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Copyright information

© Springer International Publishing AG 2018

Authors and Affiliations

  1. 1.Center for Healthy Aging, Department of Cellular and Molecular MedicineUniversity of CopenhagenCopenhagenDenmark