Related Experiment Video
Updated: Aug 13, 2026
09:12
Comparative RNA Structure Analysis of Nascent and Mature Transcripts in Saccharomyces cerevisiae
Published on: February 27, 2026
rRNA 5'ETS processing contributes to nucleolar organization and nuclear architecture
Maria Saraí Mendoza-Figueroa1, Ellen Lavorando1,2, Yulia Gonskikh1
1Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
Genes & Development
|August 11, 2026
Summary
Ribosome biogenesis is crucial for cell function. Disrupting early ribosomal RNA processing, specifically 5' external transcribed spacer (5'ETS) cleavage, alters nucleolar structure and dynamics, impacting nuclear organization.
Area of Science:
- Cell Biology
- Molecular Biology
- Genetics
Background:
- The nucleolus is a vital cellular structure for ribosome production.
- While rRNA transcription drives nucleolar assembly, the role of downstream processing in organization is unclear.
Purpose of the Study:
- To investigate how early ribosomal RNA (rRNA) processing affects nucleolar structure and organization.
- To understand the link between ribosome biogenesis and nuclear architecture.
Main Methods:
- Functional uncoupling of rRNA transcription from processing.
- Analysis of nucleolar structure, dynamics, and protein interactions (NPM1 interactome).
- Assessment of heterochromatin marker redistribution.
Main Results:
- Disruption of 5' external transcribed spacer (5'ETS) cleavage significantly alters nucleolar structure.
- Altered nucleoli show reduced dynamic exchange and changes in the NPM1 interactome.
- Defects in rRNA processing lead to heterochromatin redistribution, affecting overall nuclear organization.
Conclusions:
- Progression of pre-rRNA processing is essential for maintaining nucleolar compartmentalization.
- Early steps in ribosome biogenesis are linked to nuclear organization and nucleolar material properties.
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