exosome (RNase complex)

GO:0000178 · Ribonucleoprotein · Multiprotein complex · Proposed

A ribonuclease complex with 3'-to-5' exoribonuclease activity that participates in RNA processing and degradation. [GO:0000178]

Synonyms: exosome multienzyme ribonuclease complex; RNA exosome

Components

Component	Type	Part of / acts on	Grounding	Genes	Stoichiometry	Essential	Role
nine-subunit exosome core	Protein complex	part of	Reviewed label only (reviewed name; no accession asserted)		9 subunits	UNKNOWN	Protein barrel and cap that form the conserved scaffold of eukaryotic RNA exosome complexes. `DOI:10.1016/j.cell.2006.10.037` Liu et al. 2006 reconstituted nine-subunit yeast and human exosomes and determined the crystal structure of a human nine-subunit exosome. `RCSB_PDB:2NN6` RCSB PDB 2NN6 records the Liu et al. human RNA exosome structure with Rrp41, Rrp45, Rrp46, Rrp43, Mtr3, Rrp42, Csl4, Rrp4 and Rrp40.
Rrp44/Dis3 catalytic nuclease	Protein	part of	Reviewed label only (reviewed name; no accession asserted)	RRP44, DIS3		UNKNOWN	Catalytic 3-prime-to-5-prime exoribonuclease associated with the yeast exosome. `DOI:10.1016/s0092-8674(00)80432-8` Mitchell et al. 1997 identified Rrp44/Dis3 among the original Saccharomyces cerevisiae exosome proteins. `DOI:10.1016/j.cell.2006.10.037` Liu et al. 2006 compared yeast 9-, 10- and 11-subunit exosomes and assigned processive hydrolytic activity to Rrp44 and to the yeast 10-subunit exosome.

NCBITaxon:4932 Saccharomyces cerevisiae — COMMON: The RNase exosome is directly evidenced in budding yeast; broader archaeal and eukaryotic distributions are left for follow-up curation. [DOI:10.1016/s0092-8674(00)80432-8]

NCBITaxon:4932 Saccharomyces cerevisiae — Model eukaryote in which the RNA exosome was identified and in which 9-, 10- and 11-subunit exosome assemblies were reconstituted. [DOI:10.1016/j.cell.2006.10.037]

RNA catabolic process GO:0006401 — The RNA exosome participates in 3-prime-to-5-prime degradation of cellular RNA substrates.
- GO:0006401 GO:0006401 is the Gene Ontology biological-process term for RNA catabolic process.
- DOI:10.1016/j.cell.2006.10.037 Liu et al. 2006 analyzed reconstituted RNA exosome activities on generic, structured, AU-rich and polyadenylated RNA substrates.
RNA processing GO:0006396 — The RNA exosome participates in processing RNA precursors into mature products.
- GO:0006396 GO:0006396 is the Gene Ontology biological-process term for RNA processing.
- DOI:10.1016/s0092-8674(00)80432-8 Mitchell et al. 1997 showed that S. cerevisiae exosome components are required for 5.8S rRNA 3-prime processing.

The conserved nine-subunit RNA exosome core and associated Rrp44/Dis3 catalytic nuclease form a yeast 10-subunit exosome that acts on RNA substrates.

Subject	Predicate	Object	Evidence
nine-subunit exosome core	scaffolds	exosome (RNase complex)	`DOI:10.1016/j.cell.2006.10.037` Liu et al. 2006 reconstituted yeast and human nine-subunit exosomes.
Rrp44/Dis3 catalytic nuclease	provides hydrolytic activity for	exosome (RNase complex)	`DOI:10.1016/j.cell.2006.10.037` Liu et al. 2006 assigned processive hydrolytic activity to yeast Rrp44 and to the yeast 10-subunit exosome.
exosome (RNase complex)	supports	RNA catabolic process	`DOI:10.1016/j.cell.2006.10.037` Liu et al. 2006 reconstituted yeast exosomes and analyzed their RNA-degradation activities.

CURATION_TODO (OPEN): Resolve exact source-neutral InterPro, Pfam, GO or Complex Portal groundings for the RNA exosome core and Dis3/Rrp44 nuclease; split the nine core protein families and decide whether Rrp6 belongs only on a nuclear-exosome child record when exact cross-taxon boundaries are justified. The first RNase exosome record captures the conserved core and Dis3/Rrp44 catalytic subunit as reviewed, label-only components. A follow-up curation pass should map exact family boundaries and separate cytoplasmic, nuclear, Rrp6-containing and archaeal exosome variants.

GO:0000178 Gene Ontology cellular-component term for the exosome RNase complex and its exact synonym.
GO:1905354 Gene Ontology cellular-component term for exoribonuclease complex.
GO:0006401 Gene Ontology biological-process term for RNA catabolic process.
GO:0006396 Gene Ontology biological-process term for RNA processing.
DOI:10.1016/s0092-8674(00)80432-8 Mitchell et al. 1997, The exosome: a conserved eukaryotic RNA processing complex containing multiple 3'-5' exoribonucleases, Cell.
DOI:10.1016/j.cell.2006.10.037 Liu, Greimann and Lima 2006, Reconstitution, Activities, and Structure of the Eukaryotic RNA Exosome, Cell.
RCSB_PDB:2NN6 RCSB Protein Data Bank entry for the Liu et al. 2006 human nine-subunit RNA exosome crystal structure.

2026-09-19T07:09:07Z codex · CREATED_RECORD — Scaffolded by scripts/new_record.py
2026-09-19T07:10:18Z codex · EXPANDED_RECORD — Added exosome synonymy, a protein-containing-complex parent, reviewed-label-only core/Rrp44/Rrp6 components, budding-yeast scope, RNA processing and catabolic functions, GO/DOI/PDB evidence, a nonmechanistic RNA-decay graph and a component-grounding TODO.
2026-09-19T07:24:34Z codex · ADDRESS_REVIEW — Resolved PR #1213 findings #1214 and #1215 by replacing the generic protein-containing-complex parent with GO:1905354 exoribonuclease complex and removing the nuclear Rrp6 nuclease from the generic GO:0000178 component list and functional graph.