title: The eukaryotic RNA exosome.
abstract: The eukaryotic RNA exosome is an essential multi-subunit ribonuclease complex that contributes to the degradation or processing of nearly every class of RNA in both the nucleus and cytoplasm. Its nine-subunit core shares structural similarity to phosphorolytic exoribonucleases such as bacterial PNPase. PNPase and the RNA exosome core feature a central channel that can accommodate single stranded RNA although unlike PNPase, the RNA exosome core is devoid of ribonuclease activity. Instead, the core associates with Rrp44, an endoribonuclease and processive 3'→5' exoribonuclease, and Rrp6, a distributive 3'→5' exoribonuclease. Recent biochemical and structural studies suggest that the exosome core is essential because it coordinates Rrp44 and Rrp6 recruitment, RNA can pass through the central channel, and the association with the core modulates Rrp44 and Rrp6 activities.
authors: Structural Biology Program, Sloan-Kettering Institute, 1275 York Avenue, NY, USA.
authors: Kurt
authors: K
authors: Januszyk
authors: Structural Biology Program, Sloan-Kettering Institute, 1275 York Avenue, NY, USA; Howard Hughes Medical Institute, Structural Biology Program, Sloan-Kettering Institute, 1275 York Avenue, NY, USA. Electronic address: limac@mskcc.org.
authors: Christopher D
authors: CD
authors: Lima
mesh_terms: D000818:Animals; D005095:Exoribonucleases / Q000737:chemistry / Q000378:metabolism; D063326:Exosome Multienzyme Ribonuclease Complex / Q000737:chemistry / Q000378:metabolism*; D055354:Exosomes / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D008958:Models, Molecular; D012313:RNA / Q000737:chemistry / Q000378:metabolism*
chemical_list: D012313:RNA; D005095:Exoribonucleases; D063326:Exosome Multienzyme Ribonuclease Complex