Related Experiment Video
Updated: Jul 9, 2025
12:04
Examination of Mitotic and Meiotic Fission Yeast Nuclear Dynamics by Fluorescence Live-cell Microscopy
Published on: June 24, 2019
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Fission Yeast TORC1 Promotes Cell Proliferation through Sfp1, a Transcription Factor Involved in Ribosome Biogenesis
Yen Teng Tai1, Tomoyuki Fukuda2, Yuichi Morozumi1
1Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara, Japan.
Molecular and Cellular Biology
|December 5, 2023
Summary
Nutrient-activated Target of rapamycin complex 1 (TORC1) promotes cell proliferation by controlling ribosome production. This study identifies Sfp1 as a key transcription factor regulated by TORC1, linking nutrient signaling to cell growth.
Area of Science:
- Cellular biology
- Molecular genetics
- Biochemistry
Background:
- Target of rapamycin complex 1 (TORC1) integrates nutrient and growth factor signals.
- TORC1 activation promotes cellular anabolism and proliferation.
Purpose of the Study:
- To elucidate the mechanism of TORC1-mediated cell proliferation control.
- To identify key regulators of TORC1 signaling in fission yeast.
Main Methods:
- Genetic screening in fission yeast.
- Analysis of transcription factor regulation and interactions.
- Proteasomal degradation assays.
- Quantitative PCR for gene expression analysis.
Main Results:
- Sfp1, a zinc-finger transcription factor, was identified as a suppressor of TORC1 mutants.
- TORC1 phosphorylates Sfp1, preventing its proteasomal degradation.
- Sfp1, Ifh1, and Fhl1 cooperatively regulate genes involved in ribosome biosynthesis.
- Nuclear localization of Ifh1 is controlled by TORC1 and Sfp1 in response to nutrient availability.
Conclusions:
- Nutrient-dependent TORC1 signaling regulates cell proliferation through Sfp1, Ifh1, and Fhl1.
- This pathway controls the transcriptional regulation of ribosome biogenesis genes.
- The findings reveal a crucial mechanism linking nutrient sensing to cell growth.
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