In this study, Sharma et al. describe a novel cytoplasmic poly(A) binding protein, neuPABP, specifically found in postnatal brain neurons undergoing synaptogenesis. Unlike other PABPs, neuPABP does not bind eIF4G to support mRNA translation; instead, neuPABP interacts with neuron-specific, noncoding RNA BC1, as well as select ribosomal and mitochondrial mRNAs, in free ribonucleoprotein complexes, suggesting a role for neuPABP in suppressing their translation.