1. Mutations of EXOSC3/Rrp40p associated with neurological diseases impact ribosomal RNA processing functions of the exosome in S. cerevisiae
- Author
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Gillespie, Abby, Gabunilas, Jason, Jen, Joanna C, and Chanfreau, Guillaume F
- Subjects
Biological Sciences ,Bioinformatics and Computational Biology ,Genetics ,Neurodegenerative ,1.1 Normal biological development and functioning ,2.1 Biological and endogenous factors ,Underpinning research ,Aetiology ,Neurological ,Generic health relevance ,Amino Acid Sequence ,Amino Acid Substitution ,Binding Sites ,Conserved Sequence ,Exosome Multienzyme Ribonuclease Complex ,Gene Expression Regulation ,Fungal ,Humans ,Mutation ,Olivopontocerebellar Atrophies ,Protein Binding ,Protein Conformation ,alpha-Helical ,Protein Conformation ,beta-Strand ,Protein Interaction Domains and Motifs ,RNA Precursors ,RNA Processing ,Post-Transcriptional ,RNA ,Fungal ,RNA ,Ribosomal ,RNA-Binding Proteins ,Saccharomyces cerevisiae ,Saccharomyces cerevisiae Proteins ,Sequence Alignment ,Sequence Homology ,Amino Acid ,pontocerebellar hypoplasia ,exosome ,EXOSC3 ,Rrp40 ,ribosomal RNA processing ,Biochemistry and Cell Biology ,Developmental Biology ,Biochemistry and cell biology - Abstract
The RNA exosome is a conserved multiprotein complex that achieves a large number of processive and degradative functions in eukaryotic cells. Recently, mutations have been mapped to the gene encoding one of the subunits of the exosome, EXOSC3 (yeast Rrp40p), which results in pontocerebellar hypoplasia with motor neuron degeneration in human patients. However, the molecular impact of these mutations in the pathology of these diseases is not well understood. To investigate the molecular consequences of mutations in EXOSC3 that lead to neurological diseases, we analyzed the effect of three of the mutations that affect conserved residues of EXOSC3/Rrp40p (G31A, G191C, and W238R; G8A, G148C, and W195R, respectively, in human and yeast) in S. cerevisiae We show that the severity of the phenotypes of these mutations in yeast correlate with that of the disease in human patients, with the W195R mutant showing the strongest growth and RNA processing phenotypes. Furthermore, we show that these mutations affect more severely pre-ribosomal RNA processing functions of the exosome rather than other nuclear processing or surveillance functions. These results suggest that delayed or defective pre-rRNA processing might be the primary defect responsible for the pathologies detected in patients with mutations affecting EXOSC3 function in residues conserved throughout eukaryotes.
- Published
- 2017