Cryo-electron tomography of Kaposi’s sarcoma-associated herpesvirus capsids reveals dynamic scaffolding structures essential to capsid assembly and maturation

Autor: Dean H. Kedes, Binbin Deng, Christine M. O'Connor, Z. Hong Zhou
Rok vydání: 2008
Předmět:
Zdroj: Journal of Structural Biology. 161:419-427
ISSN: 1047-8477
Popis: Kaposi’s sarcoma-associated herpesvirus (KSHV) is a recently discovered DNA tumor virus that belongs to the γ-herpesvirus subfamily. Though numerous studies on KSHV and other herpesviruses, in general, have revealed much about their multilayered organization and capsid structure, the herpesvirus capsid assembly and maturation pathway remains poorly understood. Structural variability or irregularity of the capsid internal scaffolding core and the lack of adequate tools to study such structures have presented major hurdles to earlier investigations employing more traditional cryo-electron microscopy (cryoEM) single particle reconstruction. In this study, we used cryo-electron tomography (cryoET) to obtain three-dimensional reconstructions of individual KSHV capsids, allowing direct visualization of the capsid internal structures and systematic comparison of the scaffolding cores for the first time. We show that B-capsids are not a structurally homogenous group; rather, they represent an ensemble of “B-capsid-like” particles whose inner scaffolding is highly variable, possibly representing different intermediates existing during the KSHV capsid assembly and maturation. This information, taken together with previous observations, has allowed us to propose a detail pathway of herpesvirus capsid assembly and maturation.
Databáze: OpenAIRE
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