Calcium signaling through a Transient Receptor Channel is important for Toxoplasma gondii growth
Abstract
Transient Receptor Potential (TRP) channels participate in calcium ion (Ca2+) influx and intracellular Ca2+ release. TRP channels have not been studied in Toxoplasma gondii or any other apicomplexan parasite. In this work we characterize TgGT1_310560, a protein predicted to possess a TRP domain (TgTRPPL-2) and determined its role in Ca2+ signaling in T. gondii, the causative agent of toxoplasmosis. TgTRPPL-2 localizes to the plasma membrane and the endoplasmic reticulum (ER) of T. gondii. The ΔTgTRPPL-2 mutant was defective in growth and cytosolic Ca2+ influx from both extracellular and intracellular sources. Heterologous expression of TgTRPPL-2 in HEK-3KO cells allowed its functional characterization. Patching of ER-nuclear membranes demonstrates that TgTRPPL-2 is a non-selective cation channel that conducts Ca2+. Pharmacological blockers of TgTRPPL-2 inhibit Ca2+ influx and parasite growth. This is the first report of an apicomplexan ion channel that conducts Ca2+ and may initiate a Ca2+ signaling cascade that leads to the stimulation of motility, invasion and egress. TgTRPPL-2 is a potential target for combating Toxoplasmosis.
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All data generated or analysed during this study are included in the manuscript and supporting files.
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Funding
National Institutes of Health (AI154931)
- Silvia NJ Moreno
National Institutes of Health (AI128356)
- Silvia NJ Moreno
National Institutes of Health (T32AI060546)
- Karla Marie Marquez-Nogueras
National Institutes of Health (DK101585)
- Ivana Y Kuo
The funders had no role in study design, data collection, and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Marquez-Nogueras et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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