title: The eukaryotic RNA exosome: same scaffold but variable catalytic subunits.
abstract: The RNA exosome is a versatile ribonucleolytic protein complex that participates in a multitude of cellular RNA processing and degradation events. It consists of an invariable nine-subunit core that associates with a variety of enzymatically active subunits and co-factors. These contribute to or even provide the catalytic activity and substrate specificity of the complex. The S. cerevisiae exosome has been intensively studied since its discovery in 1997 and thus serves as the archetype of eukaryotic exosomes. Notably, its catalytic potential, derived exclusively from associated subunits, differs between the nuclear and cytoplasmic versions of the complex. The same holds true for other eukaryotes, however, recent discoveries from various laboratories including our own have revealed that there are variations on this theme. Here, we review the latest findings concerning catalytic subunits of eukaryotic exosomes, and we discuss the apparent need for differential composition and subcellular distribution of exosome variants.
authors.affiliation: Department of Molecular Biology, Centre for mRNP Biogenesis and Metabolism, Aarhus University, Aarhus C, Denmark.
authors.forename: Søren
authors.initials: S
authors.lastname: Lykke-Andersen
authors.forename: Rafal
authors.initials: R
authors.lastname: Tomecki
authors.forename: Torben Heick
authors.initials: TH
authors.lastname: Jensen
authors.forename: Andrzej
authors.initials: A
authors.lastname: Dziembowski
mesh_terms: D020134:Catalytic Domain; D002466:Cell Nucleolus / Q000378:metabolism; D002467:Cell Nucleus / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D055354:Exosomes / Q000737:chemistry / Q000378:metabolism*; D012313:RNA / Q000737:chemistry / Q000378:metabolism*; D020871:RNA Stability; D012260:Ribonucleases / Q000737:chemistry / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000737:chemistry / Q000378:metabolism; D013379:Substrate Specificity
chemical_list: D012313:RNA; D012260:Ribonucleases