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ACT1-CUP1 Assays Determine the Substrate-Specific Sensitivities of Spliceosomal Mutants in Budding Yeast
Published on: June 30, 2022
Direct interaction between Utp8p and Utp9p contributes to rRNA processing in budding yeast.
Yu-Ching Huang1, Shun-Fu Tseng, Hung-Ji Tsai
1Department of Microbiology, National Taiwan University, Taipei, Taiwan.
Biochemical and Biophysical Research Communications
|February 9, 2010
Summary
The small subunit (SSU) processome requires direct interaction between Utp8p and Utp9p proteins for proper function. This interaction is crucial for efficient 18S rRNA production in yeast.
Area of Science:
- Molecular Biology
- Cell Biology
- Biochemistry
Background:
- The small subunit (SSU) processome is a vital ribonucleoprotein complex essential for ribosome biogenesis.
- This complex, comprising U3 snoRNA and numerous proteins, is conserved across species.
- In Saccharomyces cerevisiae, the SSU processome is indispensable for generating 18S ribosomal RNA (rRNA).
Purpose of the Study:
- To investigate the functional significance of the interaction between Utp8p and Utp9p within the SSU processome.
- To elucidate the role of Utp8p-Utp9p interaction in the assembly and function of the SSU processome.
- To understand how this interaction impacts rRNA processing and biosynthesis.
Main Methods:
- Site-directed mutagenesis to disrupt the Utp8p-Utp9p interaction domain.
- Analysis of rRNA processing intermediates (35S pre-rRNA to 18S pre-rRNA).
- Biochemical assays to assess protein-RNA interactions (Utp8p, Utp9p, and U3 snoRNA).
Main Results:
- Disruption of the Utp8p-Utp9p interaction impaired the processing of 35S pre-rRNA into 18S pre-rRNA.
- Loss of Utp8p-Utp9p interaction reduced Utp8p association with U3 snoRNA.
- Utp9p binding to U3 snoRNA remained unaffected when the Utp8p-Utp9p interaction was disrupted.
Conclusions:
- Direct interaction between Utp8p and Utp9p is essential for SSU processome function.
- Utp8p likely associates with the SSU processome through its interaction with Utp9p.
- Optimal rRNA biosynthesis in yeast necessitates the direct and functional interaction of Utp8p and Utp9p within the U3 snoRNP complex.
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