Transcriptional Heterogeneity of Cryptococcus gattii VGII Compared with Non-VGII Lineages Underpins Key Pathogenicity Pathways.
Transcriptional Heterogeneity of Cryptococcus gattii VGII Compared with Non-VGII Lineages Underpins Key Pathogenicity Pathways.
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DOI：
10.1128/msphere.00445-18
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发表时间：
2018-10-24
期刊：
影响因子：
4.8
通讯作者：
Cuomo CA
中科院分区：
文献类型：
--
作者：
Farrer RA;Ford CB;Rhodes J;Delorey T;May RC;Fisher MC;Cloutman-Green E;Balloux F;Cuomo CA
相关病原体的转录谱和它们对宿主诱导的胁迫的反应是其致病性的基础。宿主相互作用期间相关病原体之间的表达差异可以指示这些基因何时以及如何促成毒力，最终为这些疾病提供新的和改进的治疗策略。在本文中，我们比较了代表四个谱系的五个分离株的转录谱。gattii在丰富的媒体。我们的分析确定了关键过程，包括那些涉及细胞囊，麦角固醇的生产，黑色素，这是不同的谱系之间的差异表达，我们发现，VGII具有差异表达基因的数量方面最独特的配置文件。所有谱系也经历了几个旁系同源物的亚功能化，包括荚膜生物合成和附着基因。在与巨噬细胞共孵育期间，大多数基因出现下调，其中观察到的最大降幅为胶囊附着基因，其似乎与应激反应相协调，因为所有谱系也上调氧化应激反应基因。此外，VGII上调了许多与麦角固醇生物合成相关的基因，并从漆酶LAC 1的表达转换为离体LAC 2的表达。最后，我们看到FosB/Jun/Egr 1调节蛋白在骨髓源性巨噬细胞的早期时间点显著增加，标志着宿主对C.加提。这项工作突出了关键C的动态作用。gattii毒力基因对巨噬细胞的反应。格特隐球菌是一种致病性酵母菌，主要在免疫活性宿主中引起疾病。当雾化的酵母或孢子进入人体，引发免疫反应，包括被巨噬细胞吞噬时，感染就开始了。为了了解酵母及其哺乳动物宿主中的早期转录信号，我们对四个谱系的C. gattii（谱系VGI至IV）在感染后1、3和6 h与小鼠巨噬细胞相互作用。体外与离体基因表达水平的比较表明，谱系VGII在转录上与非VGII谱系不同，包括参与胶囊合成、胶囊附着和麦角固醇产生的基因的差异表达。几个旁系同源基因表现出亚功能的谱系之间，包括胶囊生物合成相关基因CAP 2的上调和VGIII中CAP 1的下调。分离株还通过基因相似的旁系同源物的过表达来补偿谱系特异性基因损失，包括VGIV中胶囊基因CAS 3的过表达，其已经丢失了CAS 31基因。五分之一的C.与小鼠巨噬细胞共孵育后检测到gattii基因;所有分离株均表现出氧化还原功能的高诱导和胶囊附着基因的下调。我们还发现，VGII开关表达的两个漆酶旁系同源物（从LAC 1到LAC 2）在共孵育的巨噬细胞。最后，我们发现小鼠巨噬细胞对所有四种C. gattii通过在早期时间点上调FosB/Jun/Egr 1调节蛋白。这份报告强调了表达谱的进化宽度之间的谱系C。gattii和在这个宿主-病原体界面的转录反应的多样性。重要性相关病原体的转录谱和它们对宿主诱导的胁迫的反应是其致病性的基础。宿主相互作用期间相关病原体之间的表达差异可以指示这些基因何时以及如何促成毒力，最终为这些疾病提供新的和改进的治疗策略。在本文中，我们比较了代表四个谱系的五个分离株的转录谱。gattii在丰富的媒体。我们的分析确定了关键过程，包括那些涉及细胞囊，麦角固醇的生产，黑色素，这是不同的谱系之间的差异表达，我们发现，VGII具有差异表达基因的数量方面最独特的配置文件。所有谱系也经历了几个旁系同源物的亚功能化，包括荚膜生物合成和附着基因。在与巨噬细胞共孵育期间，大多数基因出现下调，其中观察到的最大降幅为胶囊附着基因，其似乎与应激反应相协调，因为所有谱系也上调氧化应激反应基因。此外，VGII上调了许多与麦角固醇生物合成相关的基因，并从漆酶LAC 1的表达转换为离体LAC 2的表达。最后，我们看到FosB/Jun/Egr 1调节蛋白在骨髓源性巨噬细胞的早期时间点显著增加，标志着宿主对C.加提。这项工作突出了关键C的动态作用。gattii毒力基因对巨噬细胞的反应。
The transcriptional profiles of related pathogens and their responses to host-induced stresses underpin their pathogenicity. Expression differences between related pathogens during host interaction can indicate when and how these genes contribute to virulence, ultimately informing new and improved treatment strategies for those diseases. In this paper, we compare the transcriptional profiles of five isolates representing four lineages of C. gattii in rich media. Our analyses identified key processes, including those involving cell capsule, ergosterol production, and melanin, that are differentially expressed between lineages, and we found that VGII has the most distinct profile in terms of numbers of differentially expressed genes. All lineages have also undergone subfunctionalization for several paralogs, including capsule biosynthesis and attachment genes. Most genes appeared downregulated during coincubation with macrophages, with the largest decrease observed for capsule attachment genes, which appeared to be coordinated with a stress response, as all lineages also upregulated oxidative stress response genes. Furthermore, VGII upregulated many genes that are linked to ergosterol biosynthesis and switched from expression of the laccase LAC1 to expression of LAC2 ex vivo. Finally, we saw a pronounced increase in the FosB/Jun/Egr1 regulatory proteins at early time points in bone marrow-derived macrophages, marking a role in the host response to C. gattii. This work highlights the dynamic roles of key C. gattii virulence genes in response to macrophages. Cryptococcus gattii is a pathogenic yeast of humans and other animals which causes disease predominantly in immunocompetent hosts. Infection begins when aerosolized yeast or spores enter the body, triggering an immune response, including engulfment by macrophages. To understand the early transcriptional signals in both the yeast and its mammalian host, we performed a time-course dual-transcriptome sequencing (RNA-seq) experiment for four lineages of C. gattii (lineages VGI to IV) interacting with mouse macrophages at 1, 3, and 6 h postinfection. Comparisons of in vitro to ex vivo gene expression levels indicated that lineage VGII is transcriptionally divergent from non-VGII lineages, including differential expression of genes involved in capsule synthesis, capsule attachment, and ergosterol production. Several paralogous genes demonstrated subfunctionalization between lineages, including upregulation of capsule biosynthesis-related gene CAP2 and downregulation of CAP1 in VGIII. Isolates also compensate for lineage-specific gene losses by overexpression of genetically similar paralogs, including overexpression of capsule gene CAS3 in VGIV, which have lost the CAS31 gene. Differential expression of one in five C. gattii genes was detected following coincubation with mouse macrophages; all isolates showed high induction of oxidative-reduction functions and downregulation of capsule attachment genes. We also found that VGII switches expression of two laccase paralogs (from LAC1 to LAC2) during coincubation of macrophages. Finally, we found that mouse macrophages respond to all four lineages of C. gattii by upregulating FosB/Jun/Egr1 regulatory proteins at early time points. This report highlights the evolutionary breadth of expression profiles among the lineages of C. gattii and the diversity of transcriptional responses at this host-pathogen interface. IMPORTANCE The transcriptional profiles of related pathogens and their responses to host-induced stresses underpin their pathogenicity. Expression differences between related pathogens during host interaction can indicate when and how these genes contribute to virulence, ultimately informing new and improved treatment strategies for those diseases. In this paper, we compare the transcriptional profiles of five isolates representing four lineages of C. gattii in rich media. Our analyses identified key processes, including those involving cell capsule, ergosterol production, and melanin, that are differentially expressed between lineages, and we found that VGII has the most distinct profile in terms of numbers of differentially expressed genes. All lineages have also undergone subfunctionalization for several paralogs, including capsule biosynthesis and attachment genes. Most genes appeared downregulated during coincubation with macrophages, with the largest decrease observed for capsule attachment genes, which appeared to be coordinated with a stress response, as all lineages also upregulated oxidative stress response genes. Furthermore, VGII upregulated many genes that are linked to ergosterol biosynthesis and switched from expression of the laccase LAC1 to expression of LAC2 ex vivo. Finally, we saw a pronounced increase in the FosB/Jun/Egr1 regulatory proteins at early time points in bone marrow-derived macrophages, marking a role in the host response to C. gattii. This work highlights the dynamic roles of key C. gattii virulence genes in response to macrophages.