National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
GM071940
米国
National Institutes of Health/National Institute of Dental and Craniofacial Research (NIH/NIDCR)
DE025567
米国
National Institutes of Health/National Institute Of Allergy and Infectious Diseases (NIH/NIAID)
AI094386
米国
National Institutes of Health/National Center for Research Resources (NIH/NCRR)
1S10RR23057
米国
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
1U24GM116792
米国
National Science Foundation (NSF, United States)
DBI-1338135
米国
National Science Foundation (NSF, United States)
DMR-1548924
米国
引用
ジャーナル: Nature / 年: 2019 タイトル: Cryo-EM structures of herpes simplex virus type 1 portal vertex and packaged genome. 著者: Yun-Tao Liu / Jonathan Jih / Xinghong Dai / Guo-Qiang Bi / Z Hong Zhou / 要旨: Herpesviruses are enveloped viruses that are prevalent in the human population and are responsible for diverse pathologies, including cold sores, birth defects and cancers. They are characterized by ...Herpesviruses are enveloped viruses that are prevalent in the human population and are responsible for diverse pathologies, including cold sores, birth defects and cancers. They are characterized by a highly pressurized pseudo-icosahedral capsid-with triangulation number (T) equal to 16-encapsidating a tightly packed double-stranded DNA (dsDNA) genome. A key process in the herpesvirus life cycle involves the recruitment of an ATP-driven terminase to a unique portal vertex to recognize, package and cleave concatemeric dsDNA, ultimately giving rise to a pressurized, genome-containing virion. Although this process has been studied in dsDNA phages-with which herpesviruses bear some similarities-a lack of high-resolution in situ structures of genome-packaging machinery has prevented the elucidation of how these multi-step reactions, which require close coordination among multiple actors, occur in an integrated environment. To better define the structural basis of genome packaging and organization in herpes simplex virus type 1 (HSV-1), we developed sequential localized classification and symmetry relaxation methods to process cryo-electron microscopy (cryo-EM) images of HSV-1 virions, which enabled us to decouple and reconstruct hetero-symmetric and asymmetric elements within the pseudo-icosahedral capsid. Here we present in situ structures of the unique portal vertex, genomic termini and ordered dsDNA coils in the capsid spooled around a disordered dsDNA core. We identify tentacle-like helices and a globular complex capping the portal vertex that is not observed in phages, indicative of herpesvirus-specific adaptations in the DNA-packaging process. Finally, our atomic models of portal vertex elements reveal how the fivefold-related capsid accommodates symmetry mismatch imparted by the dodecameric portal-a longstanding mystery in icosahedral viruses-and inform possible DNA-sequence recognition and headful-sensing pathways involved in genome packaging. This work showcases how to resolve symmetry-mismatched elements in a large eukaryotic virus and provides insights into the mechanisms of herpesvirus genome packaging.
A: Portal protein B: Portal protein C: Portal protein D: Portal protein E: Portal protein F: Portal protein G: Portal protein H: Portal protein I: Portal protein J: Portal protein K: Portal protein L: Portal protein
解像度: 5.6 Å / 解像度の算出法: FSC 0.143 CUT-OFF / 粒子像の数: 39939 / アルゴリズム: FOURIER SPACE / 対称性のタイプ: POINT
原子モデル構築
B value: 250 / プロトコル: AB INITIO MODEL / 空間: REAL 詳細: Ab initio models were built in Coot, and then iteratively refined between real space refinement in PHENIX and manual refinement in Coot.