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Updated: Jul 19, 2026
11:12
Identification of protein complexes with quantitative proteomics in S. cerevisiae
Published on: March 4, 2009
The signal recognition particle in S. cerevisiae
1Department of Biochemistry and Biophysics, University of California, Medical School, San Francisco 94143-0448.
Cell
|October 4, 1991
Summary
Researchers identified the Saccharomyces cerevisiae signal recognition particle (SRP), crucial for protein translocation. SRP-deficient yeast cells show impaired protein targeting, though growth is not lethal, indicating partial bypass mechanisms.
Area of Science:
- Molecular Biology
- Cell Biology
- Biochemistry
Background:
- The signal recognition particle (SRP) pathway is essential for targeting proteins to the endoplasmic reticulum (ER) membrane in eukaryotes.
- Previous studies in yeast and bacteria have not fully elucidated the components of the SRP-dependent protein targeting pathway.
Purpose of the Study:
- To identify and characterize the Saccharomyces cerevisiae homolog of the signal recognition particle (SRP).
- To investigate the in vivo function of yeast SRP in protein translocation across the ER membrane.
Main Methods:
- Identification of Saccharomyces cerevisiae SRP components, including SRP54p and scR1.
- Analysis of SRP-deficient yeast cell growth and protein translocation defects in vivo.
Main Results:
- Saccharomyces cerevisiae SRP is a 16S particle containing SRP54p and scR1.
- Genes encoding scR1 and SRP54p are non-essential, but SRP-deficient cells exhibit poor growth.
- Protein translocation across the ER membrane is impaired in SRP-deficient cells, with varying defects for different proteins.
Conclusions:
- Yeast SRP plays a vital role in protein translocation, analogous to its mammalian counterpart.
- The partial bypass of SRP function in vivo and variable translocation defects may explain why SRP pathway components were not previously identified in yeast and bacteria.
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