Department of Internal Medicine, Division of Infectious Diseases and International Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida 33612, USA.
Department of Global Health, College of Public Health, University of South Florida, Tampa, Florida 33612, USA; email:
Annu Rev Microbiol. 2018 Sep 8;72:479-499. doi: 10.1146/annurev-micro-090817-062741. Epub 2018 Jun 22.
Toxoplasma gondii is a common veterinary and human pathogen that persists as latent bradyzoite forms within infected hosts. The ability of the parasite to interconvert between tachyzoite and bradyzoite is key for pathogenesis of toxoplasmosis, particularly in immunocompromised individuals. The transition between tachyzoites and bradyzoites is epigenetically regulated and coupled to the cell cycle. Recent epigenomic studies have begun to elucidate the chromatin states associated with developmental switches in T. gondii. Evidence is also emerging that AP2 transcription factors both activate and repress the bradyzoite developmental program. Further studies are needed to understand the mechanisms by which T. gondii transduces environmental signals to coordinate the epigenetic and transcriptional machinery that are responsible for tachyzoite-bradyzoite interconversion.
刚地弓形虫是一种常见的兽医和人类病原体,在感染宿主中以潜伏的缓殖子形式存在。寄生虫在速殖子和缓殖子之间相互转化的能力是弓形体病发病机制的关键,特别是在免疫功能低下的个体中。速殖子和缓殖子之间的转换受表观遗传调控,并与细胞周期偶联。最近的表观基因组学研究开始阐明与刚地弓形虫发育转换相关的染色质状态。有证据表明,AP2 转录因子既能激活又能抑制缓殖子发育程序。需要进一步的研究来了解刚地弓形虫如何将环境信号转导为协调负责速殖子-缓殖子相互转化的表观遗传和转录机制。