- The exonuclease TREX1 is in the SET complex and acts in concert with NM23-H1 to degrade DNA during granzyme A-mediated cell death. Chowdhury, D., Beresford, P.J., Zhu, P., Zhang, D., Sung, J.S., Demple, B., Perrino, F.W., Lieberman, J. Mol. Cell (2006)