InterPro domain: IPR019103

This domain is found in eukaryotic aspartyl protease DDI1 (DNA Damage Inducible protein 1; MEROPS identifier A28.001). The remarkable structural similarity between this central domain of DDI1 and the retroviral proteases suggests that DDI1 functions proteolytically during regulated protein turnover [ 1 , 2 ]. DDI1 has been shown to activate an endoplasmic-reticulum isoform of the transcription factor SKN-1 in Caenorhabditis elegans when the proteasome is dysfunctional [ 3 ]. DDI1 also has an amino-terminal ubiquitin-like domain and/or a UBA (ubiquitin-associated) domain [ 4 ].

1. Ddi1, a eukaryotic protein with the retroviral protease fold. J. Mol. Biol. 364, 376-87
2. The DNA damage-inducible UbL-UbA protein Ddi1 participates in Mec1-mediated degradation of Ho endonuclease. Mol. Cell. Biol. 25, 5355-62
3. Proteasome dysfunction triggers activation of SKN-1A/Nrf1 by the aspartic protease DDI-1. Elife 5, 33671
4. Structural studies of the yeast DNA damage-inducible protein Ddi1 reveal domain architecture of this eukaryotic protein family. Sci Rep 6