Extended PHD finger 2 found in histone-lysine N-methyltransferase 2D (KMT2D)
The extended plant homeodomain (ePHD) zinc finger is characterized as Cys2HisCys5HisCys2His. This model corresponds to the second ePHD finger of KMT2D. KMT2D, also termed ALL1-related protein (ALR), is encoded by the gene that was named myeloid/lymphoid or mixed-lineage leukemia 4 (MLL4), a fourth human homolog of Drosophila trithorax, located on chromosome 12. KMT2D enzymatically generates trimethylated histone H3 Lys 4 (H3K4me3). It plays an essential role in differentiating the human pluripotent embryonal carcinoma cell line NTERA-2 clone D1 (NT2/D1) stem cells by activating differentiation-specific genes, such as HOXA1-3 and NESTIN. It is also a part of activating signal cointegrator-2 (ASC-2)-containing complex (ASCOM) that contains the transcriptional coactivator nuclear receptor coactivator 6 (NCOA6), KMT2C and KMT2D. The ASCOM complex is critical for nuclear receptor (NR) activation of bile acid transporter genes and is down regulated in cholestasis. KMT2D contains the catalytic domain SET, five PHD fingers, two ePHD fingers, a RING finger, an HMG (high-mobility group)-binding motif, and two FY-rich regions.
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.",