Assessing the Toxoplasma Tachyzoite Cell Cycle Phases Using Fluorescent Ubiquitination-Based Cell Cycle Indicator

Area of Science:

• Parasitology
• Cell Biology
• Molecular Biology

Background:

• Toxoplasma gondii is an apicomplexan parasite causing toxoplasmosis.
• Its cell cycle regulation differs significantly from established eukaryotic models.

Purpose of the Study:

• To develop a system for real-time visualization and quantitative assessment of the T. gondii tachyzoite cell cycle.
• To investigate the intricate architecture and regulation of the apicomplexan cell cycle.

Main Methods:

• Development of a fluorescent ubiquitination-based cell cycle indicator (FUCCI) system, termed ToxoFUCCI^S.
• Application of quantitative immunofluorescence microscopy and live-cell imaging.
• Utilizing specific cell cycle markers for detailed analysis.

Main Results:

• The ToxoFUCCI^S probe enabled real-time monitoring of T. gondii cell cycle phases.
• Quantitative analysis revealed substantial overlap between S, G2, mitosis, and cytokinesis phases.
• Confirmed the complex and flexible nature of cell cycle progression in apicomplexans.

Conclusions:

• The ToxoFUCCI^S system provides new insights into apicomplexan cell cycle organization.
• This tool facilitates the study of cell cycle dynamics in T. gondii.
• Understanding the T. gondii cell cycle is crucial for developing targeted interventions.