In the process of mRNA degradation, seems to play a role in mRNA decapping. Component of a complex containing DCP2 and DCP1A which functions in decapping of ARE-containing mRNAs. Promotes complex formation between DCP1A and DCP2. Enhances the catalytic activity of DCP2 (in vitro). Part of a decapping complex consisting of DCP1A, DCP2, EDC3, EDC4 and probably DDX6. Part of a complex consisting of DCP1A, EDC3, EDC4 and DDX6. Part of a complex consisting of DCP1B, EDC3, EDC4 and DDX6. Interacts with DCP2 (PubMed:16364915). Interacts with RC3H1 (By similarity). Interacts with NBDY (PubMed:27918561). Interacts with TEX19 (By similarity). Interacts with LSM14A (PubMed:29510985). Interacts with DDX6 (PubMed:31422817). Belongs to the WD repeat EDC4 family. Extended N-terminus.