TREX2 is one of two major human 3\' to 5\' exonucleases which are required for checkpoint signaling after DNA damage. While the related protein TREX1 is required for ATR expression and mutations in this gene result in Aicardi-Goutieres syndrome, chilblain lupus, and Cree encephalitis, less is known about TREX2. Like TREX1, TREX2 is ubiquitously expressed in all tissues examined. X-ray crystallography studies of TREX2-single strand DNA complexes revealed that TREX2 binds DNA as a dimer and may act to displace the second DNA strand, suggesting that TREX2 unzips and denatures double stranded DNA and feed the substrate DNA strand into the TREX2 active site. At least two isoforms of TREX2 are known to exist.
Alternate names: 3'-5' exonuclease TREX2, Three prime repair exonuclease 2