The family includes proteins coded by three members of the d4 gene family, DPF1 (neuro-d4), DPF2 (ubi-d4/Requiem), and DPF3 (cer-d4), which function as transcription factors and are involved in transcriptional regulation of genes by changing the condensed/decondensed state of chromatin in the nucleus. DPF2 is ubiquitously expressed and it acts as a transcription factor that may participate in developmentally programmed cell death. DPF1 and DPF3 are expressed predominantly in neural tissues, and they may be involved in the transcription regulation of neuro-specific gene clusters. The d4 family proteins show distinct domain organization with domain 2/3 in the N-terminal region, a Cys2His2 (C2H2) zinc finger or Kruppel-type zinc finger in the central part and two adjacent plant homeodomain (PHD) fingers (d4-domain) in the C-terminal part of the molecule. This model corresponds to the first PHD finger.
Jiyao W et al.(2023). "The conserved domain database in 2023.",