CRISPR/Cas9 and genetic screens in malaria parasites : small genomes, big impact

The ∼30 Mb genomes of the Plasmodium parasites that cause malaria each encode ∼5000 genes, but the functions of the majority remain unknown. This is due to a paucity of functional annotation from sequence homology, which is compounded by low genetic tractability compared with many model organisms. I...

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Detalles Bibliográficos
Autores principales: Ishizaki, Takahiro, Hernandez, Sophia, Paoletta, Martina, Sanderson, Theo, Bushell, Ellen S. C.
Formato: info:ar-repo/semantics/artículo
Lenguaje:Inglés
Publicado: Portland Press 2022
Materias:
Acceso en línea:http://hdl.handle.net/20.500.12123/12437
https://portlandpress.com/biochemsoctrans/article/50/3/1069/231360/CRISPR-Cas9-and-genetic-screens-in-malaria
https://doi.org/10.1042/BST20210281
Descripción
Sumario:The ∼30 Mb genomes of the Plasmodium parasites that cause malaria each encode ∼5000 genes, but the functions of the majority remain unknown. This is due to a paucity of functional annotation from sequence homology, which is compounded by low genetic tractability compared with many model organisms. In recent years technical breakthroughs have made forward and reverse genome-scale screens in Plasmodium possible. Furthermore, the adaptation of Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) and CRISPR-Associated protein 9 (CRISPR/Cas9) technology has dramatically improved gene editing efficiency at the single gene level. Here, we review the arrival of genetic screens in malaria parasites to analyse parasite gene function at a genome-scale and their impact on understanding parasite biology. CRISPR/Cas9 screens, which have revolutionised human and model organism research, have not yet been implemented in malaria parasites due to the need for more complex CRISPR/Cas9 gene targeting vector libraries. We therefore introduce the reader to CRISPR-based screens in the related apicomplexan Toxoplasma gondii and discuss how these approaches could be adapted to develop CRISPR/Cas9 based genome-scale genetic screens in malaria parasites. Moreover, since more than half of Plasmodium genes are required for normal asexual blood-stage reproduction, and cannot be targeted using knockout methods, we discuss how CRISPR/Cas9 could be used to scale up conditional gene knockdown approaches to systematically assign function to essential genes.