The Interaction between Histone Lysine Methyltransferase GLP and EZH2

Recent studies have implicated that H3K9 lysine methyltransferases (KMTs) and polycomb repressive complex2 (PRC2) act in a cross-talk. However, a connection between GLP, one of the well-known H3K9 KMTs and the EZH2, one of the core members of PRC2, has not been established. Here we not only demonstrated that there was interaction between the GLP and the EZH2 proteins in vivo, but also provided evidence that the activity of EZH2 was effected by down-regulation of GLP. In light of these observations, western blotting, co-immunoprecipitation and qRT-PCR were performed to explore in GLP siRNA KGN cells. The specific interaction between GLP and EZH2 was demonstrated with co-immunoprecipitation. Our results also indicate that the decreased level of GLP participate in the modulation of EZH2 function in vivo.Taken together, our findings identified that an unanticipated interplay between the two histone lysine methyltransferases, which is implicated in regulating of a subset of developmental genes.