EIF4E-binding protein that regulates translation and stability of mRNAs in processing bodies (P-bodies) (PubMed:25456498). Plays a key role in P-bodies to coordinate the storage of translationally inactive mRNAs in the cytoplasm and prevent their degradation (By similarity). Acts as a binding platform for multiple RNA-binding proteins: promotes deadenylation of mRNAs via its interaction with the CCR4-NOT complex, and blocks decapping via interaction with eIF4E (EIF4E and EIF4E2), thereby protecting deadenylated and repressed mRNAs from degradation (By similarity). Component of a multiprotein complex that sequesters and represses translation of proneurogenic factors during neurogenesis (PubMed:25456498). Promotes miRNA-mediated translational repression (By similarity). Involved in mRNA translational repression mediated by the miRNA effector TNRC6B by protecting TNRC6B-targeted mRNAs from decapping and subsequent decay (By similarity). Required for the formation of P-bodies (By similarity). Also acts as a nucleoplasmic shuttling protein, which mediates the nuclear import of EIF4E and DDX6 by a piggy-back mechanism (By similarity). Interacts (via YXXXXLphi motif) with EIF4E (PubMed:16343815). Interacts (via YXXXXLphi motif) with EIF4E2 (By similarity). Interacts with DDX6. Interacts with CSDE1/UNR (By similarity). Interacts with CNOT1; promoting association with the CCR4-NOT complex (By similarity). Interacts with LSM14A; promoting EIF4ENIF1 localization to P-bodies (By similarity). Interacts with PATL1 (By similarity). Interacts with importin beta only in the presence of importin alpha, suggesting a direct interaction with importin alpha (By similarity). Interacts with APOBEC3G in an RNA-dependent manner (By similarity). Predominantly cytoplasmic (By similarity). Mainly localizes to processing bodies (P-bodies) (By similarity). Shuttles between the nucleus and the cytoplasm in a CRM1-dependent manner. Localization to nuclear foci and speckles requires active transcription (By similarity). Highly expressed in developing oocytes. Intrinsically disordered protein with multiple low-complexity regions that confer binding to multiple RNA translation, deadenylation and decapping factors. The YXXXXLphi motif mediates interaction with eIF4E (EIF4E and EIF4E2). Phosphorylation by MAPK8/JNK1 and or MAPK9/JNK2 in response to oxidative stress promotes P-body assembly (By similarity). Phosphorylated during meiotic maturation (PubMed:16343815). Belongs to the 4E-T/EIF4E-T family.