Related Experiment Video

Updated: Feb 27, 2026

Genetic Manipulation in Δku80 Strains for Functional Genomic Analysis of Toxoplasma gondii
09:52

Genetic Manipulation in Δku80 Strains for Functional Genomic Analysis of Toxoplasma gondii

Published on: July 12, 2013

17.7K

The Toxoplasma gondii inhibitor-2 regulates protein phosphatase 1 activity through multiple motifs

Quentin Deveuve1, Kevin Lesage1, Thomas Mouveaux1

  • 1Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Centre d'Infection et d'Immunité de Lille, F-59000, Lille, France.

Parasitology Research
|July 2, 2017
PubMed

Insights

Toxoplasma gondii inhibitor-2 (TgI2) protein regulates the activity of TgPP1 phosphatase. Specific motifs in TgI2 are crucial for this inhibition, mirroring functions in higher eukaryotes.

Area of Science:

  • Parasitology
  • Molecular Biology
  • Biochemistry

Background:

  • Toxoplasma gondii possesses a complex life cycle requiring precise regulation of cellular processes.
  • Protein kinases are known regulators in T. gondii, but protein phosphatases and their regulators remain understudied.
  • Understanding these regulatory mechanisms is crucial for parasite survival and host interaction.

Purpose of the Study:

  • To characterize the molecular and functional aspects of the T. gondii inhibitor-2 (TgI2) protein.
  • To investigate the interaction between TgI2 and T. gondii protein phosphatase 1 (TgPP1).
  • To elucidate the role of specific TgI2 motifs in modulating TgPP1 activity.

Main Methods:

  • Molecular characterization of the TgI2 protein.
  • Functional assays to assess TgPP1 phosphatase activity.
  • Analysis of conserved motifs (SILK and RVxF) within TgI2.

Main Results:

  • TgI2 was identified as the T. gondii ortholog of inhibitor-2.
  • TgI2 contains conserved motifs essential for interacting with and modulating TgPP1 activity.
  • TgI2 acts as a potent inhibitor of TgPP1 phosphatase activity.
  • The SILK and RVxF motifs of TgI2 are critical for regulating TgPP1.

Conclusions:

  • TgI2 is a key regulator of TgPP1 activity in T. gondii.
  • The inhibitory mechanism of TgI2 on TgPP1 is conserved with inhibitor-2 proteins in higher eukaryotes.
  • This study provides novel insights into the post-translational regulation of T. gondii.
Keywords:
Cell-cycleHYNEInhibitor-2PP1PhosphatasePlasmodiumRVxFSILKToxoplasma

More Related Videos

Forward Genetics Screens Using Macrophages to Identify Toxoplasma gondii Genes Important for Resistance to IFN-γ-Dependent Cell Autonomous Immunity11:21

Forward Genetics Screens Using Macrophages to Identify Toxoplasma gondii Genes Important for Resistance to IFN-γ-Dependent Cell Autonomous Immunity

Published on: March 12, 2015

11.5K
Author Spotlight: Identifying Compensatory Pathways in Malaria Parasites Containing Hypomorphic Allele of Essential Protein Kinases09:13

Author Spotlight: Identifying Compensatory Pathways in Malaria Parasites Containing Hypomorphic Allele of Essential Protein Kinases

Published on: November 22, 2024

1.9K

Related Concept Videos

Protein Kinases and Phosphatases02:54

Protein Kinases and Phosphatases

Proteins undergo chemical modifications that trigger changes in the charge, structure, and conformation of the proteins. Phosphorylation, acetylation, glycosylation, nitrosylation, ubiquitination, lipidation, methylation, and proteolysis are various protein modifications that regulate protein activity. Such modifications are usually enzyme-driven.
Protein kinases
Many proteins in the cell are regulated by phosphorylation, the addition of a phosphate group. A family of enzymes called kinases...
15.3K
The JAK-STAT Signaling Pathway01:20

The JAK-STAT Signaling Pathway

Several cytokine receptors have tightly bound Janus kinase or JAK proteins attached at their cytosolic tail. Small signaling molecules such as cytokines, growth hormones, or prolactins bind to the cytokine receptors and initiate their dimerization. The dimerization brings the cytosolic JAKs together that trans-phosphorylate and activates each other. The activated JAKs now phosphorylate cytosolic tails of the cytokine receptors, which serve as binding sites for adaptor proteins such as  SH2...
13.4K
PI3K/mTOR/AKT Signaling Pathway01:22

PI3K/mTOR/AKT Signaling Pathway

The mammalian target of rapamycin  (mTOR) is a serine/threonine kinase that regulates growth, proliferation, and cell survival in response to hormones, growth factors, or nutrient availability. This kinase exists in two structurally and functionally distinct forms: mTOR complex 1  (mTORC1) and mTOR complex 2  (mTORC2). The first form (mTORC1) is composed of a rapamycin-sensitive Raptor and proline-rich Akt substrate, PRAS40. In contrast,  mTORC2 consists of a...
5.9K
Allosteric Proteins-ATCase01:19

Allosteric Proteins-ATCase

Binding sites linkages can regulate a protein's function.  For example, enzyme activity is often regulated through a feedback mechanism where the end product of the biochemical process serves as an inhibitor.
Aspartate transcarbamoylase (ATCase) is a cytosolic enzyme that catalyzes the condensation of L-aspartate and carbamoyl phosphate to  N-carbamoyl-L-aspartate. This reaction is the first step in pyrimidine biosynthesis. UTP and CTP, the end products of the pyrimidine synthesis...
6.7K
Amplifying Signals via Enzymatic Cascade01:22

Amplifying Signals via Enzymatic Cascade

When a ligand binds to a cell-surface receptor, the receptor's intracellular domain changes shape, which may either activate its enzyme function or allow its binding to other molecules. The initial signal is amplified by most signal transduction pathways. This means that a single ligand molecule can activate multiple molecules of a downstream target. Proteins that relay a signal are most commonly phosphorylated at one or more sites, activating or inactivating the protein. Kinases catalyze...
18.7K
Phosphorylation01:02

Phosphorylation

The addition or removal of phosphate groups from proteins is the most common chemical modification that regulates cellular processes. These modifications can affect the structure, activity, stability, and localization of proteins within cells as well as their interactions with other proteins.
During phosphorylation, protein kinases transfer the terminal phosphate group of ATP to specific amino acid side chains of substrate proteins. Serine, threonine, and tyrosine are the most commonly...
54.9K