Figure 5.

Possible functions of the Mtr4/NRDE-2 complex in various cellular processes.

The role of the Mtr4/NRDE-2 complex in the DDR might involve interaction with the Ku70/80 heterodimer, which recognizes DSBs. Its interaction with PARP1 may stimulate the activation of the DNA-dependent protein kinase catalytic subunit (DNA-Pkcs), a NHEJ factor that also interacts with the Ku complex. NRDE-2 and Mtr4 appear to have independent roles in transcription regulation. While NRDE-2 can have a negative effect on transcription, it seems to resolve R loops at the 3ʹ end of certain genes. According to [24], Mtr4 might also promote R-loop resolution, at least in certain circumstances.