ジャーナル: Sci Adv / 年: 2024 タイトル: The nucleocapsid architecture and structural atlas of the prototype baculovirus define the hallmarks of a new viral realm. 著者: Bronte A Johnstone / Joshua M Hardy / Jungmin Ha / Anamarija Butkovic / Paulina Koszalka / Cathy Accurso / Hariprasad Venugopal / Alex de Marco / Mart Krupovic / Fasséli Coulibaly / 要旨: Baculovirus is the most studied insect virus owing to a broad ecological distribution and ease of engineering for biotechnological applications. However, its structure and evolutionary place in the ...Baculovirus is the most studied insect virus owing to a broad ecological distribution and ease of engineering for biotechnological applications. However, its structure and evolutionary place in the virosphere remain enigmatic. Using cryo-electron microscopy, we show that the nucleocapsid forms a covalently cross-linked helical tube protecting a highly compacted 134-kilobase pair DNA genome. The ends of the tube are sealed by the base and cap substructures, which share a 126-subunit hub but differ in components that promote actin tail-mediated propulsion and nuclear entry of the nucleocapsid, respectively. Unexpectedly, sensitive searches for hidden evolutionary links show that the morphogenetic machinery and conserved oral infectivity factors originated within the lineage of baculo-like viruses (class ). The unique viral architecture and structural atlas of hallmark proteins firmly place these viruses into a separate new realm, the highest taxonomy rank, and provide a structural framework to expand their use as sustainable bioinsecticides and biomedical tools.
凍結剤: ETHANE / チャンバー内湿度: 100 % / チャンバー内温度: 277.15 K / 装置: FEI VITROBOT MARK IV
詳細
A suspension of AcMNPV viruses was purified from cell culture supernatant using sucrose gradient ultracentrifugation. Sucrose was removed after purification through dialysis.
選択した数: 143933 詳細: Particles were picked using a trained Topaz model, trained using manual picking of nucleocapsid ends from 700 micrographs
CTF補正
ソフトウェア - 名称: cryoSPARC (ver. 4.1.2) 詳細: Defocus values were estimated using patch CTF estimation, and CTF correction was performed during 3D reconstruction タイプ: NONE