ジャーナル: Nat Microbiol / 年: 2021 タイトル: Cryo-EM structures of Lassa and Machupo virus polymerases complexed with cognate regulatory Z proteins identify targets for antivirals. 著者: Xin Xu / Ruchao Peng / Qi Peng / Min Wang / Ying Xu / Sheng Liu / Xiaolin Tian / Haiteng Deng / Yimin Tong / Xiaoyou Hu / Jin Zhong / Peiyi Wang / Jianxun Qi / George F Gao / Yi Shi / 要旨: Zoonotic arenaviruses can lead to life-threating diseases in humans. These viruses encode a large (L) polymerase that transcribes and replicates the viral genome. At the late stage of replication, ...Zoonotic arenaviruses can lead to life-threating diseases in humans. These viruses encode a large (L) polymerase that transcribes and replicates the viral genome. At the late stage of replication, the multifunctional Z protein interacts with the L polymerase to shut down RNA synthesis and initiate virion assembly. However, the mechanism by which the Z protein regulates the activity of L polymerase is unclear. Here, we used cryo-electron microscopy to resolve the structures of both Lassa and Machupo virus L polymerases in complex with their cognate Z proteins, and viral RNA, to 3.1-3.9 Å resolutions. These structures reveal that Z protein binding induces conformational changes in two catalytic motifs of the L polymerase, and restrains their conformational dynamics to inhibit RNA synthesis, which is supported by hydrogen-deuterium exchange mass spectrometry analysis. Importantly, we show, by in vitro polymerase reactions, that Z proteins of Lassa and Machupo viruses can cross-inhibit their L polymerases, albeit with decreased inhibition efficiencies. This cross-reactivity results from a highly conserved determinant motif at the contacting interface, but is affected by other variable auxiliary motifs due to the divergent evolution of Old World and New World arenaviruses. These findings could provide promising targets for developing broad-spectrum antiviral drugs.
分子量: 54.938 Da / 分子数: 1 / 由来タイプ: 合成 / 式: Mn / タイプ: SUBJECT OF INVESTIGATION
研究の焦点であるリガンドがあるか
Y
-
実験情報
-
実験
実験
手法: 電子顕微鏡法
EM実験
試料の集合状態: PARTICLE / 3次元再構成法: 単粒子再構成法
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試料調製
構成要素
ID
名称
タイプ
Entity ID
Parent-ID
由来
1
Lassa virus polymerase in complex with 3'-vRNA and Z mutant (F36A).
COMPLEX
#1-#3
0
MULTIPLESOURCES
2
LassavirusZprotein
COMPLEX
#1
1
MULTIPLESOURCES
3
3-'vRNA promoter
COMPLEX
#2
1
SYNTHETIC
4
Lassaviruspolymerase
COMPLEX
#3
1
MULTIPLESOURCES
分子量
値: 0.27 MDa / 実験値: YES
由来(天然)
ID
Entity assembly-ID
生物種
Ncbi tax-ID
2
1
Lassa mammarenavirus (ウイルス)
11620
3
3
Lassa mammarenavirus (ウイルス)
11620
由来(組換発現)
ID
Entity assembly-ID
生物種
Ncbi tax-ID
2
1
Escherichia coli (大腸菌)
562
3
3
Spodoptera frugiperda (ツマジロクサヨトウ)
7108
緩衝液
pH: 7.5
試料
濃度: 1 mg/ml / 包埋: NO / シャドウイング: NO / 染色: NO / 凍結: YES
試料支持
詳細: The film was designed with regular 1.2/1.3 micron holey partterns, similar to the Quantifoil 1.2/1.3 holey grids. グリッドの材料: NICKEL/TITANIUM / グリッドのサイズ: 300 divisions/in. / グリッドのタイプ: Quantifoil R1.2/1.3
急速凍結
装置: FEI VITROBOT MARK IV / 凍結剤: ETHANE / 湿度: 100 % / 凍結前の試料温度: 277 K