Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
RNA Biol. 2021 May;18(5):759-766. doi: 10.1080/15476286.2021.1875184. Epub 2021 Jan 30.
Epstein-Barr virus (EBV) was the first human cancer-causing virus to be discovered over fifty years ago. Given its relatively large genome size for a virus and hence the capacity to store more than mere protein-coding information, EBV also harbours genetic material for producing an array of distinct noncoding (nc)RNAs. The double-stranded nature of its DNA genome allows the utilization of the whole gamut of ncRNA types, including both RNA polymerase II and III transcripts, in devising a sophisticated strategy to ensure its replication upon infection in host cells and evasion of host immune responses. Owing to the development of sensitive technologies in recent years, mostly entailing next-generation sequencing, the list of ncRNA types generated by EBV has expanded now to include two RNAs (EBER1 and EBER2) best categorized as long ncRNAs, dozens of microRNAs, one small nucleolar RNA, stable intronic sequence RNAs, and the most recently discovered circular RNAs. With the application of cutting-edge technology, the molecular mechanisms of some of these noncoding transcripts are beginning to emerge, while others remain yet to be elucidated. As viruses often take advantage of existing molecular pathways established by the host, it is likely that further novel concepts of the greatly unexplored noncoding world can be learned from studying the many EBV ncRNAs.
爱泼斯坦-巴尔病毒(EBV)是五十多年前发现的第一种致癌人类病毒。鉴于其相对较大的病毒基因组大小,因此能够存储不仅仅是蛋白质编码信息,EBV 还拥有产生一系列不同非编码(nc)RNA 的遗传物质。其 DNA 基因组的双链性质允许利用包括 RNA 聚合酶 II 和 III 转录物在内的全套 ncRNA 类型,设计出一种复杂的策略,以确保其在感染宿主细胞时的复制,并逃避宿主免疫反应。由于近年来敏感技术的发展,主要涉及下一代测序,EBV 产生的 ncRNA 类型列表现在已扩展到包括两种 RNA(EBER1 和 EBER2),最好归类为长 ncRNA,数十种 microRNAs,一种小核仁 RNA,稳定的内含子序列 RNA,以及最近发现的环状 RNA。随着尖端技术的应用,其中一些非编码转录物的分子机制开始显现,而其他机制仍有待阐明。由于病毒通常利用宿主建立的现有分子途径,因此从研究 EBV 的许多 ncRNA 中可以了解到尚未探索的非编码世界的一些新概念。