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PP2A-B55: substrates and regulators in the control of cellular functions
Priya Amin1, Sushil Awal1, Suzanne Vigneron1
1Centre de Recherche en Biologie Cellulaire de Montpellier (CRBM), CNRS UMR 5237, Université de Montpellier, 1919 Route de Mende, Montpellier Cedex 5, Montpellier, 34293, France.
Oncogene
|October 23, 2021
Summary
Protein phosphatase 2A (PP2A) holoenzyme, specifically PP2A-B55, is crucial for cell homeostasis and cancer. This review details its substrates, regulation, and specificity, highlighting its role in cell signaling.
Area of Science:
- Molecular Biology
- Cell Signaling
- Biochemistry
Background:
- Protein phosphatase 2A (PP2A) is a key serine/threonine phosphatase regulating cell signaling by dephosphorylating proteins.
- PP2A functions through various heterotrimeric complexes with distinct substrate specificities.
- The PP2A-B55 holoenzyme is a critical component of this phosphatase class.
Purpose of the Study:
- To comprehensively review the direct substrates of the PP2A-B55 holoenzyme.
- To elucidate the impact of PP2A-B55 on diverse cell signaling cascades.
- To detail the regulatory mechanisms, including inhibitors Arpp19 and ENSA, and the upstream kinase Greatwall.
Main Methods:
- Literature review of identified direct substrates of PP2A-B55.
- Analysis of signaling pathways affected by PP2A-B55 activity.
- Examination of molecular features governing PP2A-B55 substrate specificity and regulation.
Main Results:
- Identification of direct substrates and their roles in cell signaling.
- Description of the negative regulatory roles of Arpp19 and ENSA, controlled by Greatwall kinase.
- Elucidation of molecular determinants for PP2A-B55 substrate specificity and temporal dephosphorylation patterns.
Conclusions:
- PP2A-B55 is a vital enzyme for maintaining cell homeostasis.
- Dysregulation of PP2A-B55 is implicated in cancer development.
- This review serves as a consolidated resource on PP2A-B55 holoenzyme function and regulation.
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