Related Experiment Video
Updated: Aug 18, 2026

Analysis of Cell Cycle Position in Mammalian Cells
Published on: January 21, 2012
The retinoblastoma protein and the cell cycle
M Sopta1, B L Gallie, R M Gill
1Division of Immunology and Cancer Research, Hospital for Sick Children Research Institute, Toronto, Ontario, Canada.
Abstract:
Although mutations of the retinoblastoma gene (RB1) contribute to malignant progression in many types of tumor, the role of RB1 mutation in cancer initiation is highly restricted to the rare embryonic tumor, retinoblastoma. However, RB1 is expressed and its product, p110RB1, is regulated through the cell cycle in many tissues. This apparent paradox may be clarified by the emerging evidence that p110RB1 functions as a regulator of transcription of cell cycle genes. Tissue specific effects may be determined by the cellular proteins that interact with p110RB1, or by cell type-specific expression of target genes regulated by p110RB1.
Related Concept Videos
Negative Regulator Molecules
Inhibition of Cdk Activity
The Retinoblastoma Gene
The first-ever tumor suppressor gene called Rb was identified in retinoblastoma - a rare eye tumor in children. In inherited forms of the disease, a child inherits one defective copy of the Rb gene, which predisposes them to retinoblastoma. However,...
Inhibition of CDK Activity
The Retinoblastoma Gene
The first-ever tumor suppressor gene called Rb was identified in retinoblastoma - a rare eye tumor in children. In inherited forms of the disease, a child inherits one defective copy of the Rb gene, which predisposes them to retinoblastoma. However,...
The Cell Cycle Control System
Cyclins and cyclin-dependent kinases (Cdks) are the primary cell cycle regulators and function at the cell...

