RNA-binding protein involved in translationally coupled mRNA turnover. Implicated with other RNA-binding proteins in the cytoplasmic deadenylation/translational and decay interplay of the FOS mRNA mediated by the major coding-region determinant of instability (mCRD) domain. Required for efficient formation of stress granules. Component of a multi subunit autoregulatory ribonucleoprotein complex (ARC), at least composed of IGF2BP1, PABPC1 and CSDE1. Interacts with STRAP. Part of a complex associated with the FOS mCRD domain and consisting of PABPC1, PAIP1, HNRPD and SYNCRIP. The interaction with PABPC1 is direct and RNA-independent. Interacts with EIF4ENIF1/4E-T.