Part of a post-splicing multiprotein complex involved in both mRNA nuclear export and mRNA surveillance. Involved in nonsense-mediated decay (NMD) of mRNAs containing premature stop codons. Component of the exosome 3'->5' exoribonuclease complex, a complex that degrades inherently unstable mRNAs containing AU-rich elements (AREs) within their 3' untranslated regions. Required for the 3'processing of the 7S pre-RNA to the mature 5.8S rRNA. Could be an exonuclease . Plays a role in replication-dependent histone mRNA degradation. Mediates the association of MTR4, C1D and MPP6 wth the exosome and this complex is required for the maturation of 5.8S rRNA. Required for nucleolar localization of C1D
