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Updated: Jun 12, 2026
11:34
Exploring Sequence Space to Identify Binding Sites for Regulatory RNA-Binding Proteins
Published on: August 9, 2019
Regulation of ribonucleotide reductase by Spd1 involves multiple mechanisms
Konstantinos Nestoras1, Asma Hadi Mohammed, Ann-Sofie Schreurs
1Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Brighton BN19RQ, United Kingdom.
Genes & Development
|June 3, 2010
Summary
Fission yeast RNR inhibitor Spd1 regulates R2 nuclear import but primarily restrains RNR activity through a novel mechanism independent of localization, modulating complex architecture for dNTP synthesis.
Area of Science:
- Biochemistry
- Molecular Biology
- Genetics
Background:
- Deoxyribonucleotide triphosphate (dNTP) levels are crucial for maintaining genomic integrity.
- Ribonucleotide reductase (RNR) controls dNTP synthesis and is tightly regulated.
- RNR regulation involves allosteric control, transcriptional regulation, inhibitory proteins, and subunit localization.
Purpose of the Study:
- To investigate the role of the fission yeast RNR inhibitor Spd1.
- To determine how Spd1 interacts with RNR subunits and affects its regulation.
- To elucidate novel mechanisms of RNR regulation.
Main Methods:
- Characterization of Spd1's intrinsic disorder and interaction with RNR subunits (R1 and R2).
- Analysis of Spd1's effect on R2 nuclear import.
- In vivo studies to assess RNR inhibition by Spd1.
Main Results:
- Spd1 is intrinsically disordered and regulates R2 nuclear import.
- Spd1 interacts with both R1 and R2 subunits.
- Spd1's primary inhibition of RNR in vivo is independent of R2 subcellular localization.
- A novel mechanism involving RNR complex architecture modulation for dNTP synthesis regulation was identified.
Conclusions:
- Spd1 plays a complex role in RNR regulation beyond controlling R2 localization.
- RNR complex architecture modulation represents a new regulatory pathway for dNTP synthesis.
- Understanding these regulatory mechanisms is key to maintaining genomic stability.
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