Exosome complex component RRP4 is a non-catalytic component of the RNA exosome complex which has 3'->5' exoribonuclease activity and participates in a multitude of cellular RNA processing and degradation events. It consists of a N-terminal beta-sandwich hybrid domain (Pfam:PF14382), a central S1 domain and a C-terminal KH domain (Pfam:PF15985). This entry represents the S1 RNA binding domain, which has an OB fold [1,2].

1: Reconstitution, activities, and structure of the eukaryotic RNA exosome. Liu Q, Greimann JC, Lima CD; Cell. 2006;127:1223-1237. PMID:17174896

2: Human cell growth requires a functional cytoplasmic exosome, which is involved in various mRNA decay pathways. van Dijk EL, Schilders G, Pruijn GJ; RNA. 2007;13:1027-1035. PMID:17545563