培养的绵羊小胶质细胞中痒病朊病毒传播的转录组学决定因素
Transcriptomic Determinants of Scrapie Prion Propagation in Cultured Ovine Microglia.
作者信息
Muñoz-Gutiérrez Juan F, Pierlé Sebastián Aguilar, Schneider David A, Baszler Timothy V, Stanton James B
机构信息
Department of Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, Washington, United States of America.
United States Department of Agriculture, Agricultural Research Service, Pullman, Washington, United States of America.
出版信息
PLoS One. 2016 Jan 25;11(1):e0147727. doi: 10.1371/journal.pone.0147727. eCollection 2016.
Susceptibility to infection by prions is highly dependent on the amino acid sequence and host expression of the cellular prion protein (PrPC); however, cellular expression of a genetically susceptible PrPC is insufficient. As an example, it has been shown in cultured cells that permissive and resistant sublines derived from the same parental population often have similar expression levels of PrPC. Thus, additional cellular factors must influence susceptibility to prion infection. The aim of this study was to elucidate the factors associated with relative permissiveness and resistance to scrapie prions in cultured cells derived from a naturally affected species. Two closely related ovine microglia clones with different prion susceptibility, but no detectable differences in PrPC expression levels, were inoculated with either scrapie-positive or scrapie-negative sheep brainstem homogenates. Five passages post-inoculation, the transcriptional profiles of mock and infected clones were sequenced using Illumina technology. Comparative transcriptional analyses identified twenty-two differentially transcribed genes, most of which were upregulated in poorly permissive microglia. This included genes encoding for selenoprotein P, endolysosomal proteases, and proteins involved in extracellular matrix remodeling. Furthermore, in highly permissive microglia, transforming growth factor β-induced, retinoic acid receptor response 1, and phosphoserine aminotranspherase 1 gene transcripts were upregulated. Gene Set Enrichment Analysis identified proteolysis, translation, and mitosis as the most affected pathways and supported the upregulation trend of several genes encoding for intracellular proteases and ribosomal proteins in poorly permissive microglia. This study identifies new genes potentially involved in scrapie prion propagation, corroborates results from other studies, and extends those results into another cell culture model.
对朊病毒感染的易感性高度依赖于细胞朊蛋白(PrPC)的氨基酸序列和宿主表达;然而,具有遗传易感性的PrPC的细胞表达并不充分。例如,在培养细胞中已表明,来自同一亲本群体的允许性和抗性亚系通常具有相似的PrPC表达水平。因此,其他细胞因子必定会影响对朊病毒感染的易感性。本研究的目的是阐明与天然感染物种来源的培养细胞中对羊瘙痒病朊病毒的相对允许性和抗性相关的因素。用羊瘙痒病阳性或阴性绵羊脑干匀浆接种两个密切相关的具有不同朊病毒易感性但PrPC表达水平无明显差异的绵羊小胶质细胞克隆。接种后传代五次,使用Illumina技术对模拟和感染克隆的转录谱进行测序。比较转录分析确定了22个差异转录基因,其中大多数在允许性较差的小胶质细胞中上调。这包括编码硒蛋白P、溶酶体蛋白酶以及参与细胞外基质重塑的蛋白质的基因。此外,在允许性高的小胶质细胞中,转化生长因子β诱导、视黄酸受体反应1和磷酸丝氨酸转氨酶1基因转录本上调。基因集富集分析确定蛋白水解、翻译和有丝分裂是受影响最大的途径,并支持了在允许性较差的小胶质细胞中几个编码细胞内蛋白酶和核糖体蛋白的基因的上调趋势。本研究确定了可能参与羊瘙痒病朊病毒传播的新基因,证实了其他研究的结果,并将这些结果扩展到另一个细胞培养模型中。