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Spatiotemporal Analysis of Cytokinetic Events in Fission Yeast
Published on: February 20, 2017
G1 control in yeast and animal cells
S I Reed1, C Wittenberg, D J Lew
1Department of Molecular Biology, Research Institute of Scripps Clinic, La Jolla, California 92037.
Cold Spring Harbor Symposia on Quantitative Biology
|January 1, 1991
Summary
In yeast, G1 cyclins regulate the Cdc28 protein kinase to control cell cycle START. This kinase may directly regulate DNA replication genes, but its precise role in START remains under investigation.
Area of Science:
- Cell Biology
- Molecular Biology
- Genetics
Background:
- Cyclins and Cdc28 protein kinase are key regulators of the G1 phase cell cycle checkpoint in yeast.
- Cell cycle control involves regulating G1 cyclin synthesis and stability, which impacts Cdc28 kinase activity.
- The specific substrates of Cdc28 kinase critical for cell cycle progression through START are not fully identified.
Purpose of the Study:
- To investigate the substrates of Cdc28 protein kinase and their role in regulating the START transition in the yeast cell cycle.
- To explore the potential role of Cdc28 kinase in regulating the transcription of genes essential for DNA replication.
- To compare the mechanisms of G1 cell cycle regulation in yeast with those in animal cells.
Main Methods:
- The study focuses on analyzing the regulatory mechanisms of G1 cyclins and Cdc28 protein kinase activity in yeast.
- Investigates the transcriptional regulation of DNA replication genes by Cdc28 kinase.
- Compares yeast cell cycle regulation with emerging findings in animal cells, including cyclins and p34 kinases.
Main Results:
- Evidence suggests Cdc28 protein kinase activity directly influences the transcription of genes required for DNA replication.
- The precise role of this transcriptional activation in executing the START event is yet to be determined.
- The situation in animal cells is more complex, with multiple cyclins and p34s identified, but their G1 functions are unclear.
Conclusions:
- G1 cyclins and Cdc28 kinase are crucial for regulating the START event in yeast.
- Cdc28 kinase may directly control the initiation of S phase by regulating transcription factors.
- Further research is needed to elucidate the precise substrates and functions of G1 cyclins and p34 kinases in animal cell cycle progression, with tumor suppressors like p105RB being potential targets.
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