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Updated: Jun 10, 2026
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Analysis of Cell Cycle Position in Mammalian Cells
Published on: January 21, 2012
Primate-specific RFPL1 gene controls cell-cycle progression through cyclin B1/Cdc2 degradation.
J Bonnefont1, T Laforge, O Plastre
1Department of Pathology and Immunology, School of Medicine, University of Geneva, Rue Michel-Servet 1, Geneva, Switzerland.
Cell Death and Differentiation
|August 21, 2010
Summary
Human RFPL1 protein regulates cell-cycle progression by delaying mitosis entry. This primate-specific gene
Area of Science:
- Cell Biology
- Developmental Biology
- Genetics
Background:
- Ret finger protein-like 1 (RFPL1) is a primate-specific gene regulated by Pax6, crucial for development.
- The cellular functions of RFPL1, particularly its role in cell-cycle regulation, remain largely unknown.
Purpose of the Study:
- To investigate the role of human RFPL1 (hRFPL1) in cell-cycle progression.
- To elucidate the mechanism by which hRFPL1 influences cell division and proliferation.
Main Methods:
- Studied hRFPL1 expression in HeLa cells, examining the effect of p53 binding on its promoter.
- Analyzed hRFPL1's impact on cell number, cell-cycle phases (G2/M), and key regulatory proteins like cyclin B1 and Cdc2.
- Investigated the role of kinase activity (PKC, Cdc2) and proteasome-dependent degradation in hRFPL1's function.
Main Results:
- hRFPL1 expression, enhanced by p53, reduced cell number via a kinase-dependent pathway.
- hRFPL1 activity led to cell cycle arrest in the G2/M phase, with decreased cyclin B1 and Cdc2 levels.
- Cytoplasmic localization of hRFPL1 inhibited cyclin B1 and Cdc2 accumulation, delaying mitotic entry and lengthening the G2 phase.
Conclusions:
- hRFPL1 functions as a cell-cycle inhibitor, specifically by prolonging the G2 phase and delaying mitosis.
- The antiproliferative effect of hRFPL1, mediated by cyclin B1 and Cdc2 downregulation, offers insights into primate-specific developmental processes.
- RFPL1's role in cell-cycle lengthening contributes to understanding its function during cell differentiation.
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