Key component of the 4EHP-GYF2 complex, a multiprotein complex that acts as a repressor of translation initiation (PubMed:22751931, PubMed:31439631, PubMed:35878012). In the 4EHP-GYF2 complex, acts as a factor that bridges EIF4E2 to ZFP36/TTP, linking translation repression with mRNA decay (PubMed:31439631). Also recruits and bridges the association of the 4EHP complex with the decapping effector protein DDX6, which is required for the ZFP36/TTP-mediated down-regulation of AU-rich mRNA (PubMed:31439631). May act cooperatively with GRB10 to regulate tyrosine kinase receptor signaling, including IGF1 and insulin receptors (PubMed:12771153). In association with EIF4E2, assists ribosome-associated quality control (RQC) by sequestering the mRNA cap, blocking ribosome initiation and decreasing the translational load on problematic messages. Part of a pathway that works in parallel to RQC-mediated degradation of the stalled nascent polypeptide (PubMed:32726578). GIGYF2 and EIF4E2 work downstream and independently of ZNF598, which seems to work as a scaffold that can recruit them to faulty mRNA even if alternative recruitment mechanisms may exist (PubMed:32726578). ; (Microbial infection) Upon SARS coronavirus-2/SARS-CoV-2 infection, the interaction with non-structural protein 2 (nsp2) enhances GIGYF2 binding to EIF4E2 and increases repression of translation initiation of genes involved in antiviral innate immune response such as IFNB1.
