Methyl-CpG-binding (SmMBD2/3) and chromobox (SmCBX) proteins are required for neoblast proliferation and oviposition in the parasitic blood fluke Schistosoma mansoni.
Methyl-CpG-binding (SmMBD2/3) and chromobox (SmCBX) proteins are required for neoblast proliferation and oviposition in the parasitic blood fluke Schistosoma mansoni.
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DOI：
10.1371/journal.ppat.1007107
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发表时间：
2018-06
期刊：
影响因子：
6.7
通讯作者：
Hoffmann KF
中科院分区：
文献类型：
--
作者：
Geyer KK;Munshi SE;Whiteland HL;Fernandez-Fuentes N;Phillips DW;Hoffmann KF
虽然血吸虫病仍然是低收入到中等收入国家的一个重大健康问题，但它也是最近认识到的对经济发达地区的威胁。在研制出疫苗之前，这种被忽视的传染病主要由吡喹酮控制，吡喹酮是一种目前作用机制未知的药物。通过进一步阐明血吸虫分子组分如何合作调节寄生虫发育过程，将确定下一代目标。在这里，我们继续我们的研究，对一些表观遗传的参与者和DNA甲基化的读者，曼氏血吸虫甲基CpG结合域蛋白（SmMBD 2/3）的功能。首先，我们证明了SmMBD 2/3含有5-甲基胞嘧啶（5 mC）结合所必需的氨基酸特征，并说明了成年果蝇核提取物（雌性>雄性）含有这种活性。我们随后发现，SmMBD 2/3易位到转染的小鼠NIH-3 T3成纤维细胞的核隔室和重组SmMBD 2/3表现出5 mC结合活性。其次，利用酵母双杂交（Y2 H）筛选，我们发现SmMBD 2/3与表观遗传衔接子S. mansoni染色体盒蛋白（SmCBX）。此外，荧光原位杂交（FISH）介导的Smmbd 2/3和Smcbx的共定位间充质细胞以及体细胞和生殖干细胞证实了Y2 H的结果，并证明这些相互作用的伴侣是无处不在的表达，并发现在分化以及增殖细胞。最后，使用RNA干扰，我们揭示了Smmbd 2/3或Smcbx在成年女性中的耗尽导致增殖的体干细胞（PSC或neoblast）的数量以及体外产卵的数量显著减少（46-58%）。总的来说，这些结果进一步扩大了表观遗传过程中所涉及的染色体组成部分，并表明SmMBD 2/3和/或SmCBX生物学的药理学抑制可能被证明是有用的，在未来的血吸虫病控制策略的发展。血吸虫感染引起的血吸虫病是生活在发展中世界贫困地区的数百万受感染者的慢性残疾和衰弱病理的原因。目前，血吸虫病主要通过施用单一药物（吡喹酮）来控制，其作用机制目前尚不清楚，并且不能防止再感染或杀死幼血吸虫。因此，为了限制这种被忽视的传染病的传播并降低其全球流行率，迫切需要吡喹酮替代或替代战略。其中一种策略是确定寄生虫生物学所必需的分子靶点，并研究它们的功能丧失如何影响寄生虫的发育过程。通过这样做，可以开发新的药物靶标或候选疫苗。在这里，我们扩展了我们的工作特点的曼氏血吸虫表观遗传过程，并揭示了两个相互作用的组件（S。mansoni甲基CpG结合域蛋白、SmMBD 2/3和S. mansoni染色体盒蛋白，SmCBX）有助于维持单个最重要的寄生虫细胞群-增殖性溶酶体干细胞（或成新细胞）的增殖能力。我们还证明了这两种蛋白质是维持卵细胞生成所必需的，这是一种负责人类病理学和疾病传播的生命周期特征。开发破坏这些表观遗传参与者相互作用或抑制其活性的药物可能会突出显示控制血吸虫病的新方法。
While schistosomiasis remains a significant health problem in low to middle income countries, it also represents a recently recognised threat to more economically-developed regions. Until a vaccine is developed, this neglected infectious disease is primarily controlled by praziquantel, a drug with a currently unknown mechanism of action. By further elucidating how Schistosoma molecular components cooperate to regulate parasite developmental processes, next generation targets will be identified. Here, we continue our studies on schistosome epigenetic participants and characterise the function of a DNA methylation reader, the Schistosoma mansoni methyl-CpG-binding domain protein (SmMBD2/3). Firstly, we demonstrate that SmMBD2/3 contains amino acid features essential for 5-methyl cytosine (5mC) binding and illustrate that adult schistosome nuclear extracts (females > males) contain this activity. We subsequently show that SmMBD2/3 translocates into nuclear compartments of transfected murine NIH-3T3 fibroblasts and recombinant SmMBD2/3 exhibits 5mC binding activity. Secondly, using a yeast-two hybrid (Y2H) screen, we show that SmMBD2/3 interacts with the chromo shadow domain (CSD) of an epigenetic adaptor, S. mansoni chromobox protein (SmCBX). Moreover, fluorescent in situ hybridisation (FISH) mediated co-localisation of Smmbd2/3 and Smcbx to mesenchymal cells as well as somatic- and reproductive- stem cells confirms the Y2H results and demonstrates that these interacting partners are ubiquitously expressed and found within both differentiated as well as proliferating cells. Finally, using RNA interference, we reveal that depletion of Smmbd2/3 or Smcbx in adult females leads to significant reductions (46–58%) in the number of proliferating somatic stem cells (PSCs or neoblasts) as well as in the quantity of in vitro laid eggs. Collectively, these results further expand upon the schistosome components involved in epigenetic processes and suggest that pharmacological inhibition of SmMBD2/3 and/or SmCBX biology could prove useful in the development of future schistosomiasis control strategies. Schistosomiasis, caused by infection with blood fluke worms, is responsible for chronic disability and debilitating pathology in millions of infected individuals living in deprived regions of the developing world. Currently, schistosomiasis is primarily controlled by administration of a single drug (praziquantel) with a currently unknown mechanism of action and an inability to prevent reinfection or kill juvenile blood flukes. Therefore, to limit the spread and lower the global prevalence of this neglected infectious disease, praziquantel replacement or alternative strategies are urgently needed. One such strategy is to identify molecular targets essential for schistosome biology and to characterise how their loss of function affects parasite developmental processes. By doing so, new drug targets or vaccine candidates can be progressed. Here, we extend our work on the characterisation of Schistosoma mansoni epigenetic processes and reveal that two interacting components (S. mansoni methyl-CpG-binding domain protein, SmMBD2/3 and S. mansoni chromobox protein, SmCBX) are instrumental for maintaining the proliferative capacity of the single most important parasite cell population—proliferating schistosome stem cells (or neoblasts). We additionally demonstrate that these two proteins are necessary for maintaining schistosome egg production, a lifecycle feature responsible for human pathology and disease transmission. Developing drugs that disrupt the interaction of these epigenetic participants or inhibit their activity could highlight a novel approach for controlling schistosomiasis.
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影响因子：
3.8
作者：
Chalmers IW;Fitzsimmons CM;Brown M;Pierrot C;Jones FM;Wawrzyniak JM;Fernandez-Fuentes N;Tukahebwa EM;Dunne DW;Khalife J;Hoffmann KF
通讯作者：
Hoffmann KF
影响因子：
9.6
作者：
Cosseau C;Wolkenhauer O;Padalino G;Geyer KK;Hoffmann KF;Grunau C
通讯作者：
Grunau C
影响因子：
4.4
作者：
Geyer KK;Chalmers IW;Mackintosh N;Hirst JE;Geoghegan R;Badets M;Brophy PM;Brehm K;Hoffmann KF
通讯作者：
Hoffmann KF
影响因子：
5.8
作者：
Fernandez-Fuentes, Narcis;Rai, Brajesh K.;Fiser, Andras
通讯作者：
Fiser, Andras
影响因子：
5.3
作者：
Fujita, N;Shimotake, N;Nakao, M
通讯作者：
Nakao, M