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bioRxiv · 10.1101/2019.12.12.874305

YbeY is required for ribosome small subunit assembly and tRNA processing in human mitochondria

D'Souza, A. R.·Van Haute, L.·Powell, C. A.·Rebelo- Guiomar, P.·Rorbach, J.·Minczuk, M.
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Abstract

Mitochondria contain their own translation apparatus which enables them to produce the polypeptides encoded in their genome. The mitochondrially-encoded RNA components of the mitochondrial ribosome require various post-transcriptional processing steps. Additional protein factors are required to facilitate the biogenesis of the functional mitoribosome. We have characterised a mitochondrially-localized protein, YbeY, which interacts with the assembling mitoribosome through the small subunit. Loss of YbeY leads to a severe reduction in mitochondrial translation and a loss of cell viability, caused by less accurate mitochondrial mt-tRNASer(AGY) processing from the primary transcript and an accumulation of immature mitochondrial small subunit. Our results suggest that YbeY performs a dual function in mitochondria coupling tRNA processing to mitoribosome biogenesis. Issue SectionNucleic Acid Enzymes O_FIG O_LINKSMALLFIG WIDTH=194 HEIGHT=200 SRC="FIGDIR/small/874305v1_ufig1.gif" ALT="Figure 1"> View larger version (34K): org.highwire.dtl.DTLVardef@12f69cborg.highwire.dtl.DTLVardef@1cac774org.highwire.dtl.DTLVardef@1ec99ccorg.highwire.dtl.DTLVardef@652c59_HPS_FORMAT_FIGEXP M_FIG C_FIG

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D'Souza, A. R., Van Haute, L., Powell, C. A., Rebelo- Guiomar, P., Rorbach, J., Minczuk, M.. 2019-12-13. YbeY is required for ribosome small subunit assembly and tRNA processing in human mitochondria. https://doi.org/10.1101/2019.12.12.874305

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