Direct structural evidence supporting a revolving mechanism in DNA packaging motors

• 作者: Yao-Gen Shu Xiaolin Cheng
• 来源期刊: 生物物理学报
• 年，卷（期）: 2020,（5）
• 所属期刊栏目: COMMENTARY
• 页码范围: 155-158
• 页数: 4页
• 语种: 中文
• DOI: 10.3969/j.issn.1000-6737.2020.05.001

摘要

Viruses have evolved two strategies to package genome: either assembling a capsid around their genomes or packaging the genomes into a preformed capsid with packaging motors.Most of the doublestranded (ds) DNA viruses (e.g., tailed bacteriophages and herpesviruses) and dsRNA viruses (e.g., φ6 and φ12 bacteriophages) take the latter strategy.The packaging motors are usually called the "terminase" complex, which, in bacteriophages comprises two proteins, termed large (TerL) and small (TerS) terminases (Guo et al.1987b), while in herpesviruses contains three components-pUL15, pUL28 and pUL33.The unique φ29 motor complex lacks a TerS but instead contains a 174-nt prohead RNA (pRNA) (Guo et al.1987a).However, it has long been debated whether the viral genome packaging motors operate via a rotatory or revolving mechanism and what is their oligomeric state in action-a hexamer or a pentamer? And now, published in a recent issue of Protein & Cell, Yang et al.have hopefully ended these 20-year long fervent debates by determining high-resolution structures of the herpesvirus terminase complex to reveal the six-fold symmetry with a potential revolving mechanism (Yang et al.2020).