Hannigan Geoffrey D, Zheng Qi, Meisel Jacquelyn S, Minot Samuel S, Bushman Frederick D, Grice Elizabeth A
Department of Dermatology, University of Pennsylvania , Philadelphia, PA , USA.
One Codex , San Francisco, CA , USA.
PeerJ. 2017 Feb 7;5:e2959. doi: 10.7717/peerj.2959. eCollection 2017.
Localized genomic variability is crucial for the ongoing conflicts between infectious microbes and their hosts. An understanding of evolutionary and adaptive patterns associated with genomic variability will help guide development of vaccines and antimicrobial agents. While most analyses of the human microbiome have focused on taxonomic classification and gene annotation, we investigated genomic variation of skin-associated viral communities. We evaluated patterns of viral genomic variation across 16 healthy human volunteers. Human papillomavirus (HPV) and phages contained 106 and 465 regions of diversification, or hypervariable loci, respectively. phage genomes were minimally divergent and contained no hypervariable loci. Genes containing hypervariable loci were involved in functions including host tropism and immune evasion. HPV and phage hypervariable loci were associated with purifying selection. Amino acid substitution patterns were virus dependent, as were predictions of their phenotypic effects. We identified diversity generating retroelements as one likely mechanism driving hypervariability. We validated these findings in an independently collected skin metagenomic sequence dataset, suggesting that these features of skin virome genomic variability are widespread. Our results highlight the genomic variation landscape of the skin virome and provide a foundation for better understanding community viral evolution and the functional implications of genomic diversification of skin viruses.
局部基因组变异性对于传染性微生物与其宿主之间持续存在的冲突至关重要。了解与基因组变异性相关的进化和适应模式将有助于指导疫苗和抗菌药物的开发。虽然大多数对人类微生物组的分析都集中在分类学分类和基因注释上,但我们研究了与皮肤相关的病毒群落的基因组变异。我们评估了16名健康人类志愿者的病毒基因组变异模式。人乳头瘤病毒(HPV)和噬菌体分别含有106个和465个多样化区域,即高变位点。噬菌体基因组差异极小,且不含高变位点。含有高变位点的基因参与包括宿主嗜性和免疫逃避在内的功能。HPV和噬菌体高变位点与纯化选择相关。氨基酸取代模式取决于病毒,其表型效应的预测也是如此。我们确定多样性产生反转录元件是驱动高变异性的一种可能机制。我们在一个独立收集的皮肤宏基因组序列数据集中验证了这些发现,这表明皮肤病毒组基因组变异性的这些特征很普遍。我们的结果突出了皮肤病毒组的基因组变异图景,并为更好地理解群落病毒进化以及皮肤病毒基因组多样化的功能影响提供了基础。