Asc1, homolog of human RACK1, prevents frameshifting in yeast by ribosomes stalled at CGA codon repeats
| Autor: | Andrew S. Wolf, Elizabeth J. Grayhack |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2015 |
| Předmět: |
endocrine system
Saccharomyces cerevisiae Proteins Sequence Homology Receptors Cell Surface Saccharomyces cerevisiae Biology Receptors for Activated C Kinase Ribosome Frameshift mutation Trinucleotide Repeats GTP-Binding Proteins Humans RNA Messenger Codon Molecular Biology Adaptor Proteins Signal Transducing Genetics Base Sequence Frameshifting Ribosomal Translation (biology) Translation start site Articles Ribosomal RNA Yeast Neoplasm Proteins Protein Biosynthesis Transfer RNA Codon Terminator Transcription Initiation Site Ribosomes |
| Popis: | Quality control systems monitor and stop translation at some ribosomal stalls, but it is unknown if halting translation at such stalls actually prevents synthesis of abnormal polypeptides. In yeast, ribosome stalling occurs at Arg CGA codon repeats, with even two consecutive CGA codons able to reduce translation by up to 50%. The conserved eukaryotic Asc1 protein limits translation through internal Arg CGA codon repeats. We show that, in the absence of Asc1 protein, ribosomes continue translating at CGA codons, but undergo substantial frameshifting with dramatically higher levels of frameshifting occurring with additional repeats of CGA codons. Frameshifting depends upon the slow or inefficient decoding of these codons, since frameshifting is suppressed by increased expression of the native tRNAArg(ICG) that decodes CGA codons by wobble decoding. Moreover, the extent of frameshifting is modulated by the position of the CGA codon repeat relative to the translation start site. Thus, translation fidelity depends upon Asc1-mediated quality control. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|