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Updated: Aug 11, 2026
Isolation of mRNAs Associated with Yeast Mitochondria to Study Mechanisms of Localized Translation
Published on: March 14, 2014
The mitochondrial protein targeting suppressor (mts1) mutation maps to the mRNA-binding domain of Npl3p and affects
S Gratzer1, T Beilharz, T Beddoe
1Department of Biochemistry, La Trobe University, Bundoora 3083, Australia.
Abstract:
In all eukaryotic organisms, messenger RNA (mRNA) is synthesized in the nucleus and then exported to the cytoplasm for translation. The export reaction requires the concerted action of a large number of protein components, including a set of shuttle proteins that can exit and re-enter the nucleus through the nuclear pore complex. Here, we show that, in Saccharomyces cerevisiae, the shuttle protein Npl3p leaves the nuclear pore complex entirely and continues to function in the cytoplasm. A mutation at position 219 in its RNA-binding domain leaves Npl3p lingering in the cytoplasm associated with polysomes. Yeast cells expressing the mutant Npl3(L-219S) protein show alterations in mRNA stability that can affect protein synthesis. As a result, defects in nascent polypeptide targeting to subcellular compartments such as the mitochondria are also suppressed.
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