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Advantages and disadvantages of conditional systems for characterization of essential genes in Toxoplasma gondii

Published online by Cambridge University Press:  13 June 2014

Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
* Corresponding author: Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK. E-mail:


The dissection of apicomplexan biology has been highly influenced by the genetic tools available for manipulation of parasite DNA. Here, we describe different techniques available for the generation of conditional mutants. Comparison of the advantages and disadvantages of the three most commonly used regulation systems: the tetracycline inducible system, the regulation of protein stability and site-specific recombination are discussed. Using some previously described examples we explore some of the pitfalls involved in gene-function analysis using these systems that can lead to wrong or over-interpretation of phenotypes. We will also mention different options to standardize the application of these techniques for the characterization of gene function in high-throughput.

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Copyright © Cambridge University Press 2014 

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