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Updated: Aug 17, 2026

Analysis of Cell Cycle Position in Mammalian Cells
Published on: January 21, 2012
Interaction between the retinoblastoma protein and protein phosphatase 1 during the cell cycle
Norbert Berndt1, John W Ludlow
1Division of Hematology/Oncology, Children's Hospital Los Angeles, CA, USA.
Abstract:
The functions of the retinoblastoma protein (pRb) are in part regulated by reversible and cell cycle-dependent phosphorylation. While the regulation of pRb by cyclin-dependent kinases (Cdks) has been studied extensively, the role(s) of protein phosphatase 1 (PP1) in controlling pRb are only partially understood. In this chapter, we will describe experimental approaches to investigate the interactions between pRb and PP1. Methods will be presented to study the cell cycle-dependent dephosphorylation of pRb by various PP1 isozymes, the specificity of PP1 isozymes for distinct pRb phosphorylation sites, the dephosphorylation of pRb associated with apoptosis, and the cell cycle- and pRb-dependent phosphorylation of PP1.
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