Desjardins Christopher A, Sanscrainte Neil D, Goldberg Jonathan M, Heiman David, Young Sarah, Zeng Qiandong, Madhani Hiten D, Becnel James J, Cuomo Christina A
Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142, USA.
USDA, ARS, Center for Medical, Agricultural and Veterinary Entomology, 1600 SW 23rd Drive, Gainesville, Florida 32608, USA.
Nat Commun. 2015 May 13;6:7121. doi: 10.1038/ncomms8121.
Obligate intracellular pathogens depend on their host for growth yet must also evade detection by host defenses. Here we investigate host adaptation in two Microsporidia, the specialist Edhazardia aedis and the generalist Vavraia culicis, pathogens of disease vector mosquitoes. Genomic analysis and deep RNA-Seq across infection time courses reveal fundamental differences between these pathogens. E. aedis retains enhanced cell surface modification and signalling capacity, upregulating protein trafficking and secretion dynamically during infection. V. culicis is less dependent on its host for basic metabolites and retains a subset of spliceosomal components, with a transcriptome broadly focused on growth and replication. Transcriptional profiling of mosquito immune responses reveals that response to infection by E. aedis differs dramatically depending on the mode of infection, and that antimicrobial defensins may play a general role in mosquito defense against Microsporidia. This analysis illuminates fundamentally different evolutionary paths and host interplay of specialist and generalist pathogens.
专性细胞内病原体依赖宿主进行生长，但同时也必须逃避宿主防御系统的检测。在此，我们研究了两种微孢子虫（专性寄生的伊蚊埃哈氏微孢子虫和兼性寄生的库蚊瓦氏微孢子虫，它们都是病媒蚊子的病原体）对宿主的适应性。通过对感染时间进程进行基因组分析和深度RNA测序，揭示了这些病原体之间的根本差异。伊蚊埃哈氏微孢子虫保留了增强的细胞表面修饰和信号传导能力，在感染过程中动态上调蛋白质运输和分泌。库蚊瓦氏微孢子虫对基本代谢产物对宿主的依赖性较小，并保留了一部分剪接体成分，其转录组广泛聚焦于生长和复制。对蚊子免疫反应的转录谱分析表明，伊蚊埃哈氏微孢子虫感染引发的反应因感染模式的不同而有显著差异，并且抗菌防御素可能在蚊子抵御微孢子虫的防御中发挥普遍作用。该分析阐明了专性和兼性病原体截然不同的进化路径以及与宿主的相互作用。
