1. A budding yeast model for human disease mutations in the EXOSC2 cap subunit of the RNA exosome complex.
- Author
-
Sterrett MC, Enyenihi L, Leung SW, Hess L, Strassler SE, Farchi D, Lee RS, Withers ES, Kremsky I, Baker RE, Basrai MA, van Hoof A, Fasken MB, and Corbett AH
- Subjects
- Amino Acid Sequence, Amino Acid Substitution, Aspartic Acid chemistry, Aspartic Acid metabolism, Dwarfism enzymology, Dwarfism genetics, Dwarfism pathology, Exoribonucleases chemistry, Exoribonucleases metabolism, Exosome Multienzyme Ribonuclease Complex chemistry, Exosome Multienzyme Ribonuclease Complex metabolism, Facies, Gene Expression, Glycine chemistry, Glycine metabolism, Hearing Loss enzymology, Hearing Loss genetics, Hearing Loss pathology, Humans, Models, Biological, Models, Molecular, Protein Conformation, RNA, Fungal chemistry, RNA, Fungal metabolism, RNA-Binding Proteins chemistry, RNA-Binding Proteins metabolism, Retinitis Pigmentosa enzymology, Retinitis Pigmentosa genetics, Retinitis Pigmentosa pathology, Saccharomyces cerevisiae enzymology, Saccharomyces cerevisiae Proteins chemistry, Saccharomyces cerevisiae Proteins metabolism, Sequence Homology, Amino Acid, Syndrome, Exoribonucleases genetics, Exosome Multienzyme Ribonuclease Complex genetics, Mutation, Missense, RNA, Fungal genetics, RNA-Binding Proteins genetics, Saccharomyces cerevisiae genetics, Saccharomyces cerevisiae Proteins genetics
- Abstract
RNA exosomopathies, a growing family of diseases, are linked to missense mutations in genes encoding structural subunits of the evolutionarily conserved, 10-subunit exoribonuclease complex, the RNA exosome. This complex consists of a three-subunit cap, a six-subunit, barrel-shaped core, and a catalytic base subunit. While a number of mutations in RNA exosome genes cause pontocerebellar hypoplasia, mutations in the cap subunit gene EXOSC2 cause an apparently distinct clinical presentation that has been defined as a novel syndrome SHRF ( s hort stature, h earing loss, r etinitis pigmentosa, and distinctive f acies). We generated the first in vivo model of the SHRF pathogenic amino acid substitutions using budding yeast by modeling pathogenic EXOSC2 missense mutations (p.Gly30Val and p.Gly198Asp) in the orthologous S. cerevisiae gene RRP4 The resulting rrp4 mutant cells show defects in cell growth and RNA exosome function. Consistent with altered RNA exosome function, we detect significant transcriptomic changes in both coding and noncoding RNAs in rrp4-G226D cells that model EXOSC2 p.Gly198Asp, suggesting defects in nuclear surveillance. Biochemical and genetic analyses suggest that the Rrp4 G226D variant subunit shows impaired interactions with key RNA exosome cofactors that modulate the function of the complex. These results provide the first in vivo evidence that pathogenic missense mutations present in EXOSC2 impair the function of the RNA exosome. This study also sets the stage to compare exosomopathy models to understand how defects in RNA exosome function underlie distinct pathologies., (© 2021 Sterrett et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society.)
- Published
- 2021
- Full Text
- View/download PDF