Identification of the Polycomb repressive complex 2 and its interacting proteins in Paramecium tetraurelia

Please provide an overall description of your study, think something similar in scope to the manuscript abstractn Paramecium tetraurelia, Ezl1 (Homolog of EZH2) and PtCAF1 (homolog of RbAp46/48) play important roles in genome rearrangement by disrupting the transposon and transposon-derived DNA elimination. Their influences on are very similar, which make us speculate they belong to the same complex. After verifying their interaction, we speculate the complex is polycomb repressive complex 2 (PRC2) and want to find the other components of this complex. We first tagged PtCAF1 with FlagHA and used anti-HA antibody to enrich for the interacting proteins, coupled with mass spectrometry analyses (previous submission). In this way, we identified the core components of PRC2, as well as some interacted proteins with this complex. In a follow up dataset, we tagged two other subunits of the PRC2 complex we identified, Ezl1 and Eed, with FlagHA,used an anti-HA antibody to enrich for the interacting proteins, coupled with mass spectrometry analyses, and verified the complex.