Translation initiation requires the participation of eukaryotic translation initiation factors (eIFs). The poly (A)-binding protein (PABP) is thought to stimulate translation by promoting mRNA circularization through simultaneous interactions with eIF4Gand the 3'poly (A) tail. PABP activity is regulated by the PABP-interacting proteins (Paips), a family of proteins consistingof Paip1, a translational stimulator, and Paip2A and Paip2B, two translational inhibitors. Paip2A controls PABP homeostasisvia ubiquitination. When the cellular concentration of PABP is reduced, Paip2A becomes ubiquitinated and degraded, resultingin the relief of PABP repression. Paip1 interacts with eIF4A and eIF3, which promotes translation. The regulation of PABPactivity by Paips represents the first known mechanism for controlling PABP, adding a new layer to the existing knowledgeof PABP function.