Mutations in protein phosphatase 2A (PP2A) are connected to intellectual disability and cancer. It has been hypothesized that these mutations might disrupt the autoinhibition and phosphorylation-induced activation of PP2A. Since they are located far from both the active and substrate binding sites, it is unclear how they exert their effect. We performed allosteric pathway analysis based on molecular dynamics simulations and combined it with biochemical experiments to investigate the autoinhibition of PP2A. In the wild type (WT), the C-arm of the regulatory subunit B56δ obstructs the active and substrate binding sites exerting a dual autoinhibition effect. We find that the disease mutant, E198K, severely weakens the allosteric pathways that stabilize the C-arm in the WT. Instead, the strongest allosteric pathways in E198K take a different route that promotes exposure of the substrate binding site. To facilitate the allosteric pathway analysis, we introduce a path clustering algorithm for lumping pathways into channels. We reveal remarkable similarities between the allosteric channels of E198K and those in phosphorylation-activated WT, suggesting that the autoinhibition can be alleviated through a conserved mechanism. In contrast, we find that another disease mutant, E200K, which is in spatial proximity of E198, does not repartition the allosteric pathways leading to the substrate binding site; however, it may still induce exposure of the active site. This finding agrees with our biochemical data, allowing us to predict the activity of PP2A with the phosphorylated B56δ and provide insight into how disease mutations in spatial proximity alter the enzymatic activity in surprisingly different mechanisms.
Skip Nav Destination
Article navigation
7 June 2023
Research Article|
June 01 2023
Disease mutations and phosphorylation alter the allosteric pathways involved in autoinhibition of protein phosphatase 2A
Special Collection:
New Views of Allostery
Kirill A. Konovalov
;
Kirill A. Konovalov
(Conceptualization, Data curation, Formal analysis, Methodology, Writing – original draft, Writing – review & editing)
1
Department of Chemistry, Theoretical Chemistry Institute, University of Wisconsin-Madison
, Madison, Wisconsin 53706, USA
Search for other works by this author on:
Cheng-Guo Wu
;
Cheng-Guo Wu
(Data curation, Formal analysis, Writing – original draft)
2
Biophysics Graduate Program, University of Wisconsin-Madison
, Madison, Wisconsin 53706, USA
3
McArdle Laboratory for Cancer Research, Department of Oncology, School of Medicine and Public Health, University of Wisconsin-Madison
, Madison, Wisconsin 53705, USA
Search for other works by this author on:
Yunrui Qiu
;
Yunrui Qiu
(Data curation, Formal analysis, Methodology, Writing – original draft)
1
Department of Chemistry, Theoretical Chemistry Institute, University of Wisconsin-Madison
, Madison, Wisconsin 53706, USA
Search for other works by this author on:
Vijaya Kumar Balakrishnan;
Vijaya Kumar Balakrishnan
(Data curation, Formal analysis, Writing – original draft)
3
McArdle Laboratory for Cancer Research, Department of Oncology, School of Medicine and Public Health, University of Wisconsin-Madison
, Madison, Wisconsin 53705, USA
Search for other works by this author on:
Pankaj Singh Parihar
;
Pankaj Singh Parihar
(Data curation, Formal analysis)
3
McArdle Laboratory for Cancer Research, Department of Oncology, School of Medicine and Public Health, University of Wisconsin-Madison
, Madison, Wisconsin 53705, USA
Search for other works by this author on:
Michael S. O’Connor
;
Michael S. O’Connor
(Visualization, Writing – original draft, Writing – review & editing)
2
Biophysics Graduate Program, University of Wisconsin-Madison
, Madison, Wisconsin 53706, USA
Search for other works by this author on:
Yongna Xing;
Yongna Xing
a)
(Conceptualization, Data curation, Formal analysis, Funding acquisition, Supervision, Writing – original draft, Writing – review & editing)
2
Biophysics Graduate Program, University of Wisconsin-Madison
, Madison, Wisconsin 53706, USA
3
McArdle Laboratory for Cancer Research, Department of Oncology, School of Medicine and Public Health, University of Wisconsin-Madison
, Madison, Wisconsin 53705, USA
a)Authors to whom correspondence should be addressed: xing@oncology.wisc.edu and xhuang@chem.wisc.edu
Search for other works by this author on:
Xuhui Huang
Xuhui Huang
a)
(Conceptualization, Funding acquisition, Methodology, Project administration, Resources, Supervision, Writing – original draft, Writing – review & editing)
1
Department of Chemistry, Theoretical Chemistry Institute, University of Wisconsin-Madison
, Madison, Wisconsin 53706, USA
2
Biophysics Graduate Program, University of Wisconsin-Madison
, Madison, Wisconsin 53706, USA
a)Authors to whom correspondence should be addressed: xing@oncology.wisc.edu and xhuang@chem.wisc.edu
Search for other works by this author on:
a)Authors to whom correspondence should be addressed: xing@oncology.wisc.edu and xhuang@chem.wisc.edu
Note: This paper is part of the JCP Special Topic on New Views of Allostery.
J. Chem. Phys. 158, 215101 (2023)
Article history
Received:
March 13 2023
Accepted:
May 16 2023
Citation
Kirill A. Konovalov, Cheng-Guo Wu, Yunrui Qiu, Vijaya Kumar Balakrishnan, Pankaj Singh Parihar, Michael S. O’Connor, Yongna Xing, Xuhui Huang; Disease mutations and phosphorylation alter the allosteric pathways involved in autoinhibition of protein phosphatase 2A. J. Chem. Phys. 7 June 2023; 158 (21): 215101. https://doi.org/10.1063/5.0150272
Download citation file:
Sign in
Don't already have an account? Register
Sign In
You could not be signed in. Please check your credentials and make sure you have an active account and try again.
Pay-Per-View Access
$40.00
Citing articles via
DeePMD-kit v2: A software package for deep potential models
Jinzhe Zeng, Duo Zhang, et al.
Related Content
N-WASP is competent for downstream signaling before full release from autoinhibition
J. Chem. Phys. (March 2023)
Autoinhibitory mechanisms of ERG studied by molecular dynamics simulations
AIP Advances (January 2015)
Domain tethering impacts dimerization and DNA-mediated allostery in the human transcription factor FoxP1
J. Chem. Phys. (May 2023)
A mathematical model of phosphorylation AKT in Acute Myeloid Leukemia
AIP Conference Proceedings (April 2016)
SOS1 interacts with Grb2 through regions that induce closed nSH3 conformations
J. Chem. Phys. (July 2020)