Functional and Computational Genomics Reveal Unprecedented Flexibility in Stage-Specific Toxoplasma Metabolism
Functional and Computational Genomics Reveal Unprecedented Flexibility in Stage-Specific Toxoplasma Metabolism
复制标题
DOI：
10.1016/j.chom.2020.01.002
复制
发表时间：
2020-02-12
影响因子：
30.3
通讯作者：
Soldati-Favre, Dominique
中科院分区：
文献类型：
--
作者：
Krishnan, Aarti;Kloehn, Joachim;Soldati-Favre, Dominique
为了在不同的宿主环境中生存和增殖，具有不同的营养物质可利用性，专性细胞内寄生虫弓形虫重新编程其代谢。我们已经生成并策划了一个基因组规模的代谢模型（iTgo）的快速复制速殖子阶段，与实验观察到的表型相协调。为了验证模型预测的四种代谢途径的重要性，我们对突变寄生虫进行了深入的体外和体内表型分析，包括靶向代谢组学和所有已知代谢基因的CRISPR-Cas9适应性筛选。这导致了对寄生虫的显着灵活性的意想不到的见解，解决了在感染的急性和潜伏阶段对脂肪酸（FA），嘌呤核苷酸（AMP和GMP），维生素（吡哆醛-5P）和辅因子（血红素）的生物合成或补救的依赖性。总之，我们的实验验证的代谢网络导致更深入地了解寄生虫的生物学，为开发针对apicomplexans的治疗干预开辟了途径。
To survive and proliferate in diverse host environments with varying nutrient availability, the obligate intracellular parasite Toxoplasma gondii reprograms its metabolism. We have generated and curated a genome-scale metabolic model (iTgo) for the fast-replicating tachyzoite stage, harmonized with experimentally observed phenotypes. To validate the importance of four metabolic pathways predicted by the model, we have performed in-depth in vitro and in vivo phenotyping of mutant parasites including targeted metabolomics and CRISPR-Cas9 fitness screening of all known metabolic genes. This led to unexpected insights into the remarkable flexibility of the parasite, addressing the dependency on biosynthesis or salvage of fatty acids (FAs), purine nucleotides (AMP and GMP), a vitamin (pyridoxal-5P), and a cofactor (heme) in both the acute and latent stages of infection. Taken together, our experimentally validated metabolic network leads to a deeper understanding of the parasite's biology, opening avenues for the development of therapeutic intervention against apicomplexans.