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ARF6, PI3-kinase and host cell actin cytoskeleton in Toxoplasma gondii cell invasion

Claudio Vieira da Silva1, Erika Alves da Silva, Mário Costa Cruz

  • 1Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Av. Pará, 1720, Campus Umuarama, Uberlândia, 38400-902, MG, Brazil.

Biochemical and Biophysical Research Communications
|December 9, 2008
PubMed

Insights

Toxoplasma gondii invasion relies on host cell actin dynamics, involving ADP-ribosylation factor-6 (ARF6) recruitment to the vacuole. ARF6 activation of PI3-kinase is crucial for parasite entry and survival.

Area of Science:

  • Cell Biology
  • Parasitology
  • Molecular Biology

Background:

  • Toxoplasma gondii invades various host cells through active penetration.
  • Host actin polymerization was previously thought to be uninvolved in T. gondii invasion.
  • The parasitophorous vacuole resists host endocytic and exocytic fusion.

Purpose of the Study:

  • To investigate the role of ADP-ribosylation factor-6 (ARF6) in T. gondii host cell invasion.
  • To elucidate the molecular mechanisms underlying T. gondii invasion, focusing on host cell actin and membrane trafficking.

Main Methods:

  • Observation of ARF6 recruitment to the parasitophorous vacuole in T. gondii RH strain tachyzoites.
  • Analysis of PI3-kinase activation and phosphoinositide (PIP2 and PIP3) recruitment during invasion.
  • Assessment of host cell actin cytoskeleton integrity's importance for parasite invasion.

Main Results:

  • ARF6 is recruited to the parasitophorous vacuole during T. gondii invasion.
  • ARF6 plays a significant role in parasite cell invasion by activating PI3-kinase.
  • PI3-kinase activation leads to PIP2 and PIP3 recruitment to the parasitophorous vacuole.
  • Maintaining host cell actin cytoskeleton integrity is essential for T. gondii invasion.

Conclusions:

  • ARF6 is a key host factor recruited during T. gondii invasion.
  • The ARF6-PI3-kinase pathway is critical for T. gondii entry and vacuole formation.
  • Host actin cytoskeleton integrity is vital for successful T. gondii parasitism.

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