COP9信号小体蛋白Csn1201调控隐球菌嗜中枢神经系统感染的分子机制

Blood-brain-barrier invasion is crucial for Cryptococcus neoformans to infect central nervous system, which is a hot point in the currently research. Our previous study found that deletion of COP9 signalosome protein Csn1201 had an important impact on stress response and virulence of C. neoformans while not affecting the production of its classic virulence factors such as capsule or melanin. Furthermore, we also demonstrated that Csn1201 played an important role in cryptococcal invasion of blood-brain-barrier via cellular and animal experiments. The detailed molecular mechanisms remained to be further illuminated. In this study, we try to investigate the function of COP9 signalosome in the growth and virulence of C. neoformans via gene disruption technique combined with in vitro phenotypic assays, cellular and animal infection models. On the basis, we will focus on the molecular mechanism of Csn1201 in regulating blood brain barrier invasion of C. neoformans by utilizing functional genomic techniques such as gene disruption, co-immunoprecipitation, mass spectrometry. Our study will lay a sound theoretical basis for exploring new intervention strategies against cryptococcal infection.

宿主血脑屏障的突破是新生隐球菌中枢神经系统感染的中心环节，已成为当前学界的研究热点。我们前期研究发现，COP9信号小体蛋白Csn1201缺失对隐球菌的应激应答与致病感染具有重要功能影响，而对荚膜、黑色素等毒力因子的表达无明显影响；在此基础上结合前期细胞与动物实验结果，我们进一步发现Csn1201的毒力调控可能与其对隐球菌穿越血脑屏障的调节功能密切相关，其内在的分子调控机制亟待进一步明确。本研究拟应用基因敲除技术，结合体外表型检测、细胞和动物感染模型，综合探讨COP9信号小体对隐球菌的毒力调控效应；在此基础上，以Csn1201为重点研究目标，应用免疫共沉淀、质谱分析以及上述功能基因组学方法，深入研究Csn1201通路调控隐球菌侵袭宿主血脑屏障的内在分子机制，为探索抗隐球菌感染的新型防治策略提供新理论依据，为最终攻克临床真菌感染提供新的研究思路。

毒力因子复合体的表达与调控是新生隐球菌致病感染的中心环节，是当前学界的研究热点。COP9信号小体蛋白元件Csn1201对隐球菌的生长与毒力具有重要调控作用，其潜在的调控机制尚不甚明确。本研究首次证实Csn1201参与调节隐球菌在宿主体内的肺部增殖与血源性播散以及穿越血脑屏障过程，参与介导隐球菌感染后的宿主非保护性的Th2型免疫应答。酵母双杂交实验提示Csn1201与脂肪酸代谢、应激应答、蛋白质控及转录调控等多种生物学过程密切相关。Csn1201重要靶蛋白Liv4参与调控新生隐球菌的生长增殖、应激应答与致病感染，可能通过调节隐球菌的代谢适应力，继而调控其在宿主体内的致病毒力与免疫逃逸。我们的研究系统论证了Csn1201蛋白对隐球菌生长增殖、致病感染及免疫逃逸过程中的重要作用，为后续探索新的隐球菌临床干预靶点奠定了基础。