Transcription regulator (PubMed:23593018, PubMed:17933869). Acts as a histone chaperone that facilitates deposition of histone H3.3 (PubMed:28320872). Has a role in chromatin remodeling together with asf1 and XNP (PubMed:28320872). Has role in the transcriptional apoptotic response to oxidative and UV stress (PubMed:17933869, PubMed:23593018). Interacts with p53 (via C-terminus) (PubMed:17933869). Interacts (via C-terminus) with His3.3A and His3.3B (PubMed:28320872). Interacts with asf1 (PubMed:28320872). Localization to the nucleus is regulated by dj-1beta and oxidative stress (PubMed:23593018). Localizes to pericentric heterochromatin associated with chromosomes X and 4 (PubMed:28320872). Ubiquitously expressed with higher levels in the head (at protein level) (PubMed:23593018). Expressed in the germ line, with prominent expression in primary spermatocytes and meiotic spermatocytes (at protein level) (PubMed:28320872). In ovaries, expressed in nurse cells and in the germinal vesicle of the ovarian follicle at stage 10 (at protein level) (PubMed:28320872). Expressed in all developmental stages (PubMed:17933869). Higher level of expression detected at the end of the third larval stage, in adult females and in early embryos containing maternally deposited transcripts (PubMed:17933869). At later stages of development, specific expression can be detected in tissues containing mitotic cells such as in the brain hemispheres and imaginal disks (PubMed:17933869). Reduces longevity and female fertility, but increases resistance to oxidative stress and UV irradiation-induced pupal lethality (PubMed:23593018). Double knockouts for DJ-1beta and Daxx restore normal number of dopaminergic neurons, locomotor activity and sensitivity to oxidative stress and UV-induced damage (PubMed:23593018). RNAi-mediated knockdown results in increased resistance to oxidative stress (PubMed:23593018).