High-Throughput Measurement of Microneme Secretion in Toxoplasma gondii

Part of the Methods in Molecular Biology book series (MIMB, volume 2071)


Micronemes are specialized secretory organelles present in all motile forms of apicomplexan parasites. Microneme vesicles hold adhesins and other proteins that are secreted to facilitate parasite attachment, invasion of host cells, and egress following replication—all processes indispensable for cell-to-cell transmission of these obligate intracellular parasites. Defining the signaling pathways that lead to microneme secretion is an important part of understanding the infectious cycle of apicomplexan parasites. However, the classical method of measuring microneme secretion by immunoblotting for microneme proteins in parasite excreted/secreted antigen (ESA) preparations is low-throughput and only semiquantitative. We recently reported a new luciferase-based method for measuring microneme secretion in a 96-well format with high sensitivity in the model apicomplexan Toxoplasma gondii. Here, we aim to elaborate on this detection method and review current practices for stimulating microneme secretion in vitro.

Key words

Microneme secretion Luciferase Reporter Toxoplasma gondii 



Work in the authors’ labs was supported by an AHA grant 15POST22130001 to KMB, NIH grants AI118426 and AI034036 to LDS, and 1DP5OD017892 and 1R21AI123746 to SL.


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© Springer Science+Business Media, LLC, part of Springer Nature 2020

Authors and Affiliations

  1. 1.Department of Microbiology and ImmunologyUniversity of Oklahoma Health Sciences CenterOklahoma CityUSA
  2. 2.Whitehead Institute for Biomedical ResearchCambridgeUSA
  3. 3.Biology DepartmentMassachusetts Institute of TechnologyCambridgeUSA
  4. 4.Department of Molecular MicrobiologyWashington University School of MedicineSt. LouisUSA

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