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Updated: Jun 13, 2026
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Assessment of Selective mRNA Translation in Mammalian Cells by Polysome Profiling
Published on: October 28, 2014
Nucleoplasmic checkpoint of the 40S ribosomal decoding center maturation
Benjamin Lau1, Yi Li2, Jingyi Zhu2
1Heidelberg University Biochemistry Center (BZH), Heidelberg, Germany; Molecular Systems Biology Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany.
Cell Reports
|June 11, 2026
Summary
The essential assembly factor Rrp12 coordinates early ribosome decoding center (DC) formation. Its C-terminal truncation disrupts DC assembly, triggering a nucleoplasmic checkpoint and ensuring accurate ribosome maturation.
Area of Science:
- Molecular Biology
- Cell Biology
- Structural Biology
Background:
- The decoding center (DC) is crucial for accurate protein translation.
- Early nucleoplasmic assembly of the DC is poorly understood, unlike later cytoplasmic stages.
Purpose of the Study:
- To elucidate the regulatory mechanisms governing early nucleoplasmic DC assembly.
- To identify the role of the essential assembly factor Rrp12 in this process.
Main Methods:
- Cryo-electron microscopy of pre-40S ribosomal intermediates in Chaetomium thermophilum.
- Analysis of Rrp12 C-terminus truncation mutants.
Main Results:
- Rrp12 C-terminal truncation inhibits Utp14-Dhr1 release and displaces Tsr1.
- Truncation leads to premature h28 stabilization and prevents h44 formation.
- These defects impair 18S rRNA processing and prematurely activate the Rio1 kinase.
Conclusions:
- Rrp12 is a central coordinator of early DC assembly.
- A nucleoplasmic checkpoint regulates ribosome maturation, involving Rrp12.
- Rrp12 ensures accurate ribosome assembly and orderly maturation.
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