Essential for formation of P-bodies, cytoplasmic structures that provide storage sites for translationally inactive mRNAs and protect them from degradation (PubMed:16484376, PubMed:17074753, PubMed:29510985). Acts as a repressor of mRNA translation (PubMed:29510985). May play a role in mitotic spindle assembly (PubMed:26339800).