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Updated: Jun 20, 2025
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A Rapid High-throughput Method for Mapping Ribonucleoproteins RNPs on Human pre-mRNA
Published on: December 2, 2009
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A UTP3-dependent nucleolar translocation pathway facilitates pre-rRNA 5'ETS processing
Jiayang Bao1, Baochun Su1, Zheyan Chen2
1MOE Key Laboratory for Molecular Animal Nutrition, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China.
Nucleic Acids Research
|July 22, 2024
Summary
The study reveals how proteins enter the nucleolus to assemble the ribosome small subunit (SSU). UTP3 protein helps ferry other proteins, crucial for 5
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- The ribosome small subunit (SSU) assembly involves the SSU processome, a complex of ~70 non-ribosomal proteins.
- While SSU processome biochemical functions are known, the mechanism of component entry into the nucleolus is unclear.
Purpose of the Study:
- To systematically investigate the nucleolar localization mechanisms of SSU processome components.
- To elucidate the role of UTP3 in nucleolar import and 5'ETS processing.
Main Methods:
- Examined nucleolar localization of 50 human SSU processome components.
- Investigated UTP3's interaction with nuclear importin α.
- Utilized knockdown in human cells and loss-of-function in zebrafish models.
Main Results:
- 25 SSU processome proteins, including UTP3, localize to the nucleolus autonomously.
- UTP3/SAS10 assists the nucleolar import of 5 additional proteins, conserved in zebrafish.
- UTP3 is essential for 5'ETS processing by recruiting EXOSC10 for degradation.
Conclusions:
- UTP3 plays a dual role in SSU processome assembly: facilitating nucleolar import and mediating 5'ETS processing.
- UTP3's 'ferrying' function is conserved and crucial for ribosome biogenesis.
- Findings provide a framework for understanding cytoplasm-to-nucleolus trafficking of SSU processome components.
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