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Updated: Jul 11, 2026
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Coupled Assays for Monitoring Protein Refolding in Saccharomyces cerevisiae
Published on: July 9, 2013
Translation in Saccharomyces cerevisiae: initiation factor 4A-dependent cell-free system
S Blum1, M Mueller, S R Schmid
1Institut fuer Biochemie und Molekularbiologie, Universitaet Bern, Switzerland.
Summary
Yeast translation initiation factor (Tif) is essential for protein synthesis. This study confirms Tif
Area of Science:
- Molecular Biology
- Yeast Genetics
- Protein Synthesis
Background:
- The yeast Saccharomyces cerevisiae genes TIF1 and TIF2 encode translation initiation factor (Tif).
- Tif shares similarities in amino acid sequence and molecular weight with mammalian eukaryotic initiation factor 4A.
- The precise role of Tif in yeast translation requires clarification.
Purpose of the Study:
- To determine if Tif plays a role in yeast translation.
- To characterize Tif as a translation factor.
Main Methods:
- Production of an affinity-purified anti-Tif antibody.
- Purification of Tif from wild-type yeast cells using chromatography and antibody probing.
- Investigating the effect of Tif depletion on yeast cell growth and in vitro translation.
Main Results:
- Tif was successfully purified from wild-type yeast.
- Depletion of Tif in yeast cells led to growth arrest.
- Lysates from Tif-depleted cells were inactive in in vitro translation, but activity was restored upon Tif addition.
Conclusions:
- Tif is a crucial translation factor in yeast.
- Tif is the yeast homologue of mammalian translation initiation factor 4A.
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