Extended PHD finger found in protein Jade-1 and similar proteins
The extended plant homeodomain (ePHD) zinc finger is characterized as Cys2HisCys5HisCys2His. This model includes the ePHD finger of Jade-1. Jade-1, also termed PHD finger protein 17 (PHF17), is a novel binding partner of von Hippel-Lindau (VHL) tumor suppressor Pvhl, a key regulator of cellular oxygen sensing pathway. It is highly expressed in renal proximal tubules. Jade-1 functions as an essential regulator of multiple cell signaling pathways. It may be involved in the Serine/threonine kinase AKT/AKT1 pathway during renal cancer pathogenesis and normally prevents renal epithelial cell proliferation and transformation. It also acts as a pro-apoptotic and growth suppressive ubiquitin ligase to inhibit canonical Wnt downstream effector beta-catenin for proteasomal degradation and ASA transcription factor associated with histone acetyltransferase activity and with increased abundance of cyclin-dependent kinase inhibitor p21. Moreover, Jade-1 is required for ING4 and ING5 to associate with histone acetyltransferase (HAT) HBO1 and Eaf6 to form a HBO1 complex, and plays a role in epithelial cell regeneration. It has also been identified as a novel component of the nephrocystin protein (NPHP) complex and interacts with the ciliary protein nephrocystin-4 (NPHP4). Jade-1 contains a canonical plant homeodomain (PHD) finger followed by this non-canonical ePHD finger, both of which are zinc-binding motifs.
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.