Exosome complex exonuclease RRP4 (EC 3.1.13.-) (Ribosomal RNA- processing protein 4); Component of the exosome 3'->5' exoribonuclease complex but does not have exonuclease activity. As part of the exosome, required for the 3'-processing of the 7S pre-RNA to the mature 5.8S rRNA and for mRNA decay (359 aa)