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Genetic Manipulation in Δku80 Strains for Functional Genomic Analysis of Toxoplasma gondii
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Published on: July 12, 2013

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Protein Phosphatase 2C of Toxoplasma Gondii Interacts with Human SSRP1 and Negatively Regulates Cell Apoptosis

Xue Juan Gao1, Jun Xia Feng1, Sen Zhu1

  • 1Key Laboratory of Functional Protein Research of Guangdong Higher Education Institutes, Institute of Life and Health Engineering, Jinan University, Guangzhou 510632, Guangdong, China.

Biomedical and Environmental Sciences : BES
|November 7, 2014
PubMed
Abstract

Insights

Toxoplasma gondii phosphatase (TgPP2C) interacts with human SSRP1, inhibiting host cell apoptosis. This parasitic interaction promotes parasite growth by enhancing host cell survival.

Area of Science:

  • Parasitology
  • Molecular Biology
  • Cell Biology

Background:

  • Toxoplasma gondii (T. gondii) is an opportunistic protozoan parasite.
  • T. gondii expresses a serine-threonine phosphatase, TgPP2C, implicated in parasite growth.
  • TgPP2C's role in host cell regulation is not fully understood.

Purpose of the Study:

  • Investigate the interaction between T. gondii's TgPP2C and human structure-specific recognition protein 1 (SSRP1).
  • Determine the functional consequences of TgPP2C-SSRP1 interaction on host cell viability and apoptosis.

Main Methods:

  • Yeast two-hybrid system, His-tag pull-down, and co-immunoprecipitation assays to confirm protein interactions and map binding domains.
  • Flow cytometry using Annexin-V/PI staining and cleaved caspase-3 antibody to evaluate apoptosis.

Main Results:

  • Human SSRP1 was identified as a binding partner for TgPP2C.
  • The C-terminal region of SSRP1 (amino acids 471-538) mediates the interaction with TgPP2C.
  • Overexpression of TgPP2C reduced host cell apoptosis, including apoptosis induced by DRB (a CKII inhibitor), via enhanced SSRP1 interaction.

Conclusions:

  • TgPP2C acts as a parasitic factor that promotes host cell survival.
  • Interaction with host SSRP1 is a mechanism by which TgPP2C enhances cell viability.
  • This interaction may create a favorable environment for T. gondii proliferation within the host.
Keywords:
ApoptosisSSRP1TgPP2CToxoplasma gondii

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