Extended PHD finger found in PHD finger protein 7 (PHF7) and G2/M phase-specific E3 ubiquitin-protein ligase (G2E3)
The extended plant homeodomain (ePHD) zinc finger is characterized as Cys2HisCys5HisCys2His. This model includes the ePHD finger of PHF7 and G2E3. PHF7, also termed testis development protein NYD-SP6, is a testis-specific PHD finger-containing protein that associates with chromatin and binds histone H3 N-terminal tails with a preference for dimethyl lysine 4 (H3K4me2). It may play an important role in stimulating transcription involved in testicular development and/or spermatogenesis. PHF7 contains a PHD finger and a non-canonical ePHD finger, both of which may be involved in activating transcriptional regulation. G2E3 is a dual function ubiquitin ligase (E3) that may play a possible role in cell cycle regulation and the cellular response to DNA damage. It is essential for prevention of apoptosis in early embryogenesis. It is also a nucleo-cytoplasmic shuttling protein with DNA damage responsive localization. G2E3 contains two distinct RING-like ubiquitin ligase domains that catalyze lysine 48-linked polyubiquitination, and a C-terminal catalytic HECT domain that plays an important role in ubiquitin ligase activity and in the dynamic subcellular localization of the protein. The RING-like ubiquitin ligase domains consist of a PHD finger and an ePHD finger.
Conserved feature residue pattern:C C H C C C C C H C C H
Evidence:
Comment:based on the structure evidence that human Borjeson-Forssman-Lehmann syndrome-associated protein PHF6 (PDB 4NN2) binds three Zn2+ ions through its ePHD finger
Comment:The extended PHD finger is characterized by Cys2HisCys5HisCys2His.
Jiyao W et al.(2023). "The conserved domain database in 2023.",