Cell Death Triggered by a Putative Amphipathic Helix of Radish mosaic virus Helicase Protein Is Tightly Correlated With Host Membrane Modification.
Cell Death Triggered by a Putative Amphipathic Helix of Radish mosaic virus Helicase Protein Is Tightly Correlated With Host Membrane Modification.
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DOI：
10.1094/mpmi-01-15-0004-r
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发表时间：
2015-06
期刊：
影响因子：
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通讯作者：
M. Hashimoto;K. Komatsu;Ryo Iwai;T. Keima;K. Maejima;Takuya Shiraishi;K. Ishikawa;Tetsuya Yoshida;Yugo Kitazawa;Yukari Okano;Y. Yamaji;S. Namba
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作者：
M. Hashimoto;K. Komatsu;Ryo Iwai;T. Keima;K. Maejima;Takuya Shiraishi;K. Ishikawa;Tetsuya Yoshida;Yugo Kitazawa;Yukari Okano;Y. Yamaji;S. Namba
系统性坏死是由植物RNA病毒引起的最严重的症状之一。最近，系统性坏死被认为具有与称为过敏反应（HR）的防御反应相似的特征，过敏反应是程序性细胞死亡的一种形式。在受病毒感染的植物细胞中，宿主细胞内膜结构发生显著变化，以实现更有效的病毒复制。然而，很少有人知道这种复制相关的膜修饰是否是症状的原因。在这项研究中，我们确定了一个氨基末端的两亲性螺旋的解旋酶编码的萝卜花叶病毒（RaMV）（属Comovirus）作为诱导剂的细胞死亡在RaMV感染的植物。由两亲性螺旋引起的细胞死亡具有与HR相似的特征，例如SGT1依赖性。使用浅蓝菌素的突变分析和抑制剂测定表明，两亲性螺旋诱导的细胞死亡与内质网（ER）膜结构的显著改变密切相关。此外，两亲性螺旋的细胞死亡诱导活性在豇豆花叶病毒（豇豆花叶病毒属）和烟草环斑病毒（线虫传多角体病毒属）中是保守的，这两种病毒都被分类在Secoviridae家族中。总之，这些结果表明，与病毒细胞内复制相关的ER膜修饰可能被认为是针对植物病毒的主要防御反应。
Systemic necrosis is one of the most severe symptoms caused by plant RNA viruses. Recently, systemic necrosis has been suggested to have similar features to a defense response referred to as the hypersensitive response (HR), a form of programmed cell death. In virus-infected plant cells, host intracellular membrane structures are changed dramatically for more efficient viral replication. However, little is known about whether this replication-associated membrane modification is the cause of the symptoms. In this study, we identified an amino-terminal amphipathic helix of the helicase encoded by Radish mosaic virus (RaMV) (genus Comovirus) as an elicitor of cell death in RaMV-infected plants. Cell death caused by the amphipathic helix had features similar to HR, such as SGT1-dependence. Mutational analyses and inhibitor assays using cerulenin demonstrated that the amphipathic helix-induced cell death was tightly correlated with dramatic alterations in endoplasmic reticulum (ER) membrane structures. Furthermore, the cell death-inducing activity of the amphipathic helix was conserved in Cowpea mosaic virus (genus Comovirus) and Tobacco ringspot virus (genus Nepovirus), both of which are classified in the family Secoviridae. Together, these results indicate that ER membrane modification associated with viral intracellular replication may be recognized to prime defense responses against plant viruses.