A Novel Method to Silence Genes in Cryptosporidium

  • Alejandro Castellanos-GonzalezEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 2052)


The parasites of the genus Cryptosporidium are important causes of diarrheal diseases, specifically cryptosporidiosis, worldwide. A major bottleneck for developing drugs and vaccines against cryptosporidiosis is the lack of methods to study gene function in this parasite. Silencing of genes by RNA interference (RNAi) is a powerful method to investigate gene function that has been widely used in the identification of targets for several pathogens. Unfortunately, as Cryptosporidium does not possess the enzymes of the RNAi pathway, its genes cannot be silenced by standard siRNA technology. To circumvent that problem, we have developed a novel strategy to knock down Cryptosporidium genes by reconstituting the effector arm of the siRNA pathway. We have induced silencing of several genes in Cryptosporidium by transfecting parasites with hybrid complexes formed between recombinant human Argonaute (hAgo2) and Cryptosporidium single-stranded RNA (ssRNA). This novel methodology provides an effective strategy to study the role of selected genes in host–parasite interactions, and also can be used to identify potential targets for chemotherapy. The standardized methodology based on this strategy is described in this chapter.


Cryptosporidium Gene silencing RNAi 



This work was supported by the Bill & Melinda Gates Foundation grant: OPP1161026 and by the National Institute of Allergy and Infectious Diseases (NIH/NIAID), grant: 5R21AI12627502.


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

Authors and Affiliations

  1. 1.Infectious Disease Division, Department of Internal MedicineUniversity of Texas Medical BranchGalvestonUSA

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