Tudor domain found in PHD finger protein1 (PHF19) and similar proteins
PHF19, also called Polycomb-like protein 3 (PCL3), is a component of the Polycomb repressive complex 2 (PRC2), which is the major H3K27 methyltransferase that regulates pluripotency, differentiation, and tumorigenesis through catalysis of histone H3 lysine 27 trimethylation (H3K27me3) on chromatin. PHF19 consists of an N-terminal Tudor domain followed by two PHD domains, and a C-terminal MTF2 domain. It binds trimethylated histone H3 Lys36 (H3K36me3) through its Tudor domain and recruits the PRC2 complex and the H3K36me3 demethylase NO66 to embryonic stem cell genes during differentiation. Moreover, PHF19 and its upstream regulator, Akt, play roles in the phenotype switch of melanoma cells from proliferative to invasive states.