Related Experiment Video

Updated: May 11, 2026

A Mass Spectrometry-Based Approach to Identify Phosphoprotein Phosphatases and their Interactors
10:17

A Mass Spectrometry-Based Approach to Identify Phosphoprotein Phosphatases and their Interactors

Published on: April 29, 2022

PP2A Counterbalances Phosphorylation of pRB and Mitotic Proteins by Multiple CDKs: Potential Implications for PP2A

Alison Kurimchak1, Xavier Graña

  • 1Fels Institute for Cancer Research and Molecular Biology, Temple University School of Medicine, Philadelphia, PA, USA.

Genes & Cancer
|May 2, 2013
PubMed

Insights

Protein Phosphatase 2A (PP2A) regulates cell signaling through dephosphorylation. This review focuses on the B55α subunit

Area of Science:

  • Cellular Biology
  • Biochemistry
  • Oncology

Background:

  • Protein Phosphatase 2A (PP2A) holoenzymes are crucial serine/threonine phosphatases involved in diverse cell signaling pathways.
  • PP2A's substrate specificity is determined by regulatory B subunits, though mechanisms remain unclear.
  • PP2A acts as a tumor suppressor, with specific heterotrimeric compositions linked to this function.

Purpose of the Study:

  • To review the role of the B55α regulatory subunit and related family members in PP2A function.
  • To explore how B55α influences the phosphorylation of pocket proteins and mitotic CDK substrates.
  • To discuss the implications of PP2A dysfunction in cancer, particularly concerning B55α-mediated activities.

Main Methods:

  • Literature review focusing on PP2A, B subunits, and cancer signaling.
  • Analysis of studies investigating B55α interactions and substrate dephosphorylation.
  • Synthesis of current understanding regarding PP2A's tumor suppressor roles.

Main Results:

  • The B55α subunit plays a key role in directing PP2A activity towards specific substrates, including pocket proteins and mitotic CDK substrates.
  • Dysregulation of PP2A complexes involving B55α is implicated in cancer development and progression.
  • Understanding these specific PP2A complexes offers insights into potential therapeutic strategies for cancer.

Conclusions:

  • The B55α regulatory subunit is critical for PP2A's tumor suppressor functions by modulating key signaling pathways.
  • Further research into PP2A composition and B55α interactions is essential for understanding cancer biology.
  • Targeting PP2A complexes may represent a viable strategy for cancer therapy.
Keywords:
B55αPP2A inhibitorsPPP2R2Acyclinsp107p130tumor suppressor

More Related Videos

Assessing Cellular Target Engagement by SHP2 (PTPN11) Phosphatase Inhibitors08:45

Assessing Cellular Target Engagement by SHP2 (PTPN11) Phosphatase Inhibitors

Published on: July 17, 2020

Studying Cell Cycle-regulated Gene Expression by Two Complementary Cell Synchronization Protocols12:02

Studying Cell Cycle-regulated Gene Expression by Two Complementary Cell Synchronization Protocols

Published on: June 6, 2017

Related Concept Videos

Abnormal Proliferation02:23

Abnormal Proliferation

Under normal conditions, most adult cells remain in a non-proliferative state unless stimulated by internal or external factors to replace lost cells. Abnormal cell proliferation is a condition in which the cell's growth exceeds and is uncoordinated with normal cells. In such situations, cell division persists in the same excessive manner even after cessation of the stimuli, leading to persistent tumors. The tumor arises from the damaged cells that replicate to pass the damage to the daughter...
Negative Regulator Molecules01:23

Negative Regulator Molecules

Positive regulators allow a cell to advance through cell cycle checkpoints. Negative regulators have an equally important role as they terminate a cell’s progression through the cell cycle—or pause it—until the cell meets specific criteria.
Inhibition of Cdk Activity02:34

Inhibition of Cdk Activity

The orderly progression of the cell cycle depends on the activation of Cdk protein by binding to its cyclin partner. However, the cell cycle must be restricted when undergoing abnormal changes. Most cancers correlate to the deregulated cell cycle, and since Cdks are a central component of the cell cycle, Cdk inhibitors are extensively studied to develop anticancer agents. For instance, cyclin D associates with several Cdks, such as Cdk 4/6, to form an active complex. The cyclin D-Cdk4/6 complex...
Inhibition of CDK Activity02:34

Inhibition of CDK Activity

The orderly progression of the cell cycle depends on the activation of Cdk protein by binding to its cyclin partner. However, the cell cycle must be restricted when undergoing abnormal changes. Most cancers correlate to the deregulated cell cycle, and since Cdks are a central component of the cell cycle, Cdk inhibitors are extensively studied to develop anticancer agents. For instance, cyclin D associates with several Cdks, such as Cdk 4/6, to form an active complex. The cyclin D-Cdk4/6 complex...
DNA Damage can Stall the Cell Cycle02:36

DNA Damage can Stall the Cell Cycle

In response to DNA damage, cells can pause the cell cycle to assess and repair the breaks. However, the cell must check the DNA at certain critical stages during the cell cycle. If the cell cycle pauses before DNA replication, the cells will contain twice the amount of DNA. On the other hand, if cells arrest after DNA replication but before mitosis, they will contain four times the normal amount of DNA. With a host of specialized proteins at their disposal,cells must use the right protein at...
DNA Damage Can Stall the Cell Cycle02:36

DNA Damage Can Stall the Cell Cycle

In response to DNA damage, cells can pause the cell cycle to assess and repair the breaks. However, the cell must check the DNA at certain critical stages during the cell cycle. If the cell cycle pauses before DNA replication, the cells will contain twice the amount of DNA. On the other hand, if cells arrest after DNA replication but before mitosis, they will contain four times the normal amount of DNA. With a host of specialized proteins at their disposal,cells must use the right protein at...