Functional analysis of Sendai virus C protein

仙台病毒C蛋白的功能分析

基本信息

批准号：
12670292
负责人：
ITOH Masae
金额：
$ 2.24万
依托单位：
Osaka Prefectural Institute of Public Health
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2001
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12670292/
关键词：
Sendai virus C protein pathogenicity apoptosis necrosis interferon 抗ウイルス作用

项目摘要

(1) Mapping of the functional sites on the C protein.1) C(del10-15) mutan t: Preparing a mutant with a deletion at the position 10-15 of the C protein, we showed that amino acids at 10-15 were indispensable for inhibition of STAT1 stabilization, resistance against the anti-viral state of the host cells, suppression of apoptosis and expression of pathogenicity. These amino acids, however, were not involved in phosphorylation of STAT1, inhibition of the trans activation of ISGs as well as suppression of viral RNA polymerase activity.2) C170Ser(MVC11) mutant : A single point mutation at C170Phe→Ser demonstrated that C170 plays an important role in suppression of viral RNA polymerase activity, inhibition of STAT 1 stability and phosphorylation, inhibition of transact!vation of ISGs, suppression of apoptosis, resistance against anti-viral state of the host cells and expression of viral virulence. The Phe, however, had no relation with the formation of virus particles.(2) Mechanism ofattenua … More tion of the C protein mutant.1) Interferon sensitivity : When MVC11 was infected to interferon α/β receptor (IFNR)-knock-out mice (A129), mice exhibited only slight decrease of body weight. The result demonstrated that MVC11 was attenuated in A129 to the same degree as in ordinary mice possessing IFNR, suggesting that interferon sensitivity alone does not explain the attenuation of MVC11.2) Effect of death of infected cells : MVC11, an attenuated virus with a mutation in the C protein, induced necrosis as well as apoptosis. Death of the infected cells caused interruption of progeny virus production afterwards, and resulted in attenuation of viral pathogenicity. On the other hand, parental pathogenic virus Ml did not demonstrate significant cytopathic effect and released progeny virus continuously for a long time after infection. In the presence of caspase inhibitors which suppressed apoptosis but not necrosis, MVC11-infected cells died rapidly. These results suggested that necrosis plays an important role in causing death to attenuated virus-infected cells.(3) Mechanism ofapoptosis-induction by MVC11.Using the specific inhibitors of each caspase, we demonstrated that activation of caspase 8 occurred during apoptosis induced by MVC11. On the other hand, it was shown that caspase 9 had less relation to MVC11-induced apoptosis. FADD molecule was not involved in the activation of caspase 8.(4) Localization of C170Ser.C170Ser, when expressed independently from other MVC11 proteins, strongly interacted with cytoskeleton. The phenomenon might have some relation with induction of apoptosis by C170Ser. Less

（1）C蛋白上的功能位点的映射。1）C（del10-15）突变t：在C蛋白的位置10-15处制备具有缺失的突变体，我们表明，10-15时的氨基酸是必不可少的，对于抑制Stat1稳定性，抵抗抗宿主细胞的抗性状态的抗性和抑制性的抑制作用，并且表现为Apopoptssiss的抗性状态。然而，这些氨基酸不参与STAT1的磷酸化，ISG的反式激活的抑制以及病毒RNA聚合酶活性的抑制。2）C170SER（MVC11）突变体：C170Phe→C170在C170中起着统计性的重要作用，在C170phe中的单个点突变在C170phe中发挥了重要的作用。磷酸化，抑制ISG的交易，抑制凋亡，对宿主细胞的抗病毒状态的抗性以及病毒病毒的表达。但是，PHE与病毒颗粒的形成无关。（2）attenua的机理……C蛋白突变体的更多信息。1）干扰素敏感性：当将MVC11感染到干扰素α/β受体（IFNR）-Knock-Ot-Out小鼠（A129）时，小鼠仅略微降低了体内体重的体重。结果表明，MVC11在A129中与具有IFNR的普通小鼠的程度相同，这表明单独的干扰素敏感性不能解释MVC11.2的衰减）感染细胞死亡的影响：MVC11的效果：MVC11，一种衰减的病毒，患有C蛋白中的突变，C蛋白质，诱导的Necrissis and Apoptiss。感染细胞的死亡随后导致后代病毒的产生中断，并导致病毒致病性衰减。另一方面，父母的致病病毒ML并未表现出明显的细胞质作用，并在感染后很长一段时间内持续释放后代病毒。在抑制细胞凋亡但未坏死的caspase抑制剂的情况下，MVC11感染的细胞迅速死亡。这些结果表明，坏死在导致死亡减弱病毒感染细胞的死亡方面起着重要作用。（3）MVC11的凋亡诱导机理。使用每个caspase的特定抑制剂，我们证明了caspase 8的激活发生在MVC11诱导的凋亡过程中。另一方面，证明caspase 9与MVC11诱导的凋亡的关系较小。 FADD分子不参与caspase8的激活。（4）C170SER.C170SER的定位，当与其他MVC11蛋白独立表示时，与细胞骨架强烈相互作用。该现象可能与C170SER诱导凋亡有关。较少的