Exploring gene functions in an obligate intracellular parasite Theileria using CRISPR-Cas9 technologies


Project Description

Background:Theileria is a unique and remarkable apicomplexan parasite capable of transforming its host leukocyte into a disseminating cancer-like tumour and it is the only known example of natural reversible transformation of mammalian host leukocytes by an eukaryotic parasite. T. annulata is the causative agent of the cattle disease called tropical theileriosis, which is of major economic importance in countries in Northern Africa, The Middle East and Asia. Importantly, the tumor-like phenotype is reversed upon drug-induced parasite death. Moreover, virulent macrophages can be attenuated by multiple in vitro passages, and upon attenuation, they lose both adhesion and invasiveness. Transfection systems are available for several important species of protozoa, including the apicomplexan parasites Toxoplasma gondii, Eimeria tenella and Plasmodium spp. However, such approaches are not available for Theileria spp. Objectives:In this study, we aim to test the feasibility of new delivery systems to create genetic tools for the study of T. annulata genes. The CRISPR‐Cas9 system is a powerful tool for gene editing in various cells and organisms, but delivery of CRISPR‐Cas9 plasmids into cells or tissues is challenging, because the vectors encoding both Cas9 and sgRNA are handicapped by both a strong negative charge and a large size.Methodology:In order to achieve our objective, we propose to develop nanoparticles to deliver the CRISPR genome-editing system into T. annulata-infected leukocytes and specifically modify expressed parasite genes. This study will be performed in active collaboration with KAUST experts in the nanomaterials field.​ ​​
Program - BioScience
Division - Biological and Environmental Sciences and Engineering
Field of Study - ​Microbiology, Molecular Biology, Cell biology, Parasitology

About the

Arnab Pain

Professor, Bioscience

Arnab Pain
The primary focus of the Pathogen Genomics Laboratory is to use high-throughput sequencing and other functional genomic technologies to understand the biology and genomic diversity of a few parasitic protists and bacteria with significant impact on human and animal health. Genome and transcriptome sequencing of these organisms is a critical first step towards our understanding of how these organisms grow and thrive in a susceptible host and in other environment. A better understanding of their biology could eventually lead to the development of new intervention strategies.

Within this program, a combination of high-throughput DNA and RNA sequencing-based methods, coupled with functional genomics and bioinformatics tools are being used in the following areas of research:
  1. Genomics of Apicomplexan parasites and Chromerids and host-parasite interactions. 
  2. Molecular and genomic characterization of enteric pathogens particularly during mass gatherings 
  3. Genome variation in Mycobacteria 
  4. Development of bioinformatic tools for genome-scale data visualization and mining

Desired Project Deliverables

​This study will fill a technology gap in Theileria research by enabling systematic and genome-wide functional studies of parasite gene functions, and facilitating assessment of many aspects of the biology of this unique host-apicomplexan parasite interaction. Moreover, defined vaccines created by genetically manipulating parasite genes and validation of antigens will become a possibility.