Plays a role in DNA repair. May be a component of an E3 ubiquitin-protein ligase which promotes histone ubiquitination in response to UV irradiation. Histone ubiquitination may be important for subsequent DNA repair (By similarity). Protein modification; protein ubiquitination. Levels accumulate after the removal of the food source and increase with the onset of development (accumulation at 1-3 hours) peaking at 5-7 hours of development and declining abruptly. Not expressed by mitotically dividing cells. Not measurable during vegetative growth on bacteria. Down-regulated in response to UV-damage followed by an increase in transcription back to basal level. Shows slight increase in transcription following cisplatin treatment. Belongs to the DDB1 family.