Together with PDP1, PDP3 and PDP6, interacts with MSI4/FVE and MSI5 to suppress FLC, MAF4 and MAF5 expression by regulating the function of the PRC2 complex and modulating H3K27me3 level, thereby promoting flowering. Interacts with DEK3 (PubMed:25387881). Binds to MSI4/FVE and MSI5 (PubMed:29314758). Component of the PRC2 (polycomb repressive complex 2) complex which regulates histone methylation on histone H3K27 (By similarity). Delayed flowering associated with reduced H3K27me3 level on FLC (PubMed:29314758). The triple mutant pdp1 pdp2 pdp3 has increased levels of FLC, MAF4 and MAF5 expression, but decreased expression of FT (PubMed:29314758). Belongs to the PDP family.