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Updated: Aug 10, 2026

Analysis of Cell Cycle Position in Mammalian Cells
Published on: January 21, 2012
Cyclin-dependent kinases and pRb: regulators of the proliferation-differentiation switch
O Kranenburg1, A J van der Eb, A Zantema
1Department of Molecular Carcinogenesis, Sylvius Laboratory, Leiden University, The Netherlands.
Abstract:
The retinoblastoma susceptibility gene (RB1) is essential for normal embryonic development. Loss of RB1 leads to uncontrolled proliferation of a number of cell types but may also prevent proper terminal differentiation. The growth-suppressive and differentiation-inducing properties of pRb are impaired by cyclin-dependent kinase (cdk)-mediated phosphorylation. Hence, inhibition of cdk activity is probably a prerequisite for terminal differentiation. Indeed, forced cyclin or cdk expression can prevent terminal differentiation in various cell types, probably through inhibition of pRb and, possibly, differentiation-specific transcription factors.
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