Autophagy interferes with human cytomegalovirus genome replication, morphogenesis, and progeny release
Autophagy interferes with human cytomegalovirus genome replication, morphogenesis, and progeny release
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DOI：
10.1080/15548627.2020.1732686
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发表时间：
2020-02
期刊：
影响因子：
13.3
通讯作者：
C. Zimmermann;N. Krämer;Steffi Krauter;D. Strand;E. Sehn;U. Wolfrum;A. Freiwald;F. Butter;B. Plachter
中科院分区：
文献类型：
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作者：
C. Zimmermann;N. Krämer;Steffi Krauter;D. Strand;E. Sehn;U. Wolfrum;A. Freiwald;F. Butter;B. Plachter
摘要 病毒感染通常伴随着自噬的诱导，自噬是一种内在的细胞防御机制。疱疹病毒已经开发出逃避自噬降解并操纵宿主细胞自噬以使其受益的策略。在这里，我们讨论了巨自噬/自噬在人类巨细胞病毒复制和颗粒形态发生中的作用。我们发现自噬机制的蛋白质定位于细胞质病毒组装区室和细胞质中的包膜病毒体。令人惊讶的是，自噬受体 SQSTM1/p62 也被发现与受感染细胞核中的 HCMV 衣壳共定位。这一发现表明自噬机制在颗粒形态发生的早期核阶段就已经与 HCMV 相互作用。膜结合形式的 LC3 和几种自噬受体被包装到细胞外 HCMV 病毒体中。这表明在 HCMV 病毒粒子的二次包膜过程中包含自噬膜。为了进一步解决自噬在 HCMV 感染中的重要性，我们生成了表达蛋白酶 ATG4B (BAD-ATG4BC74A) 显性失活版本的 HCMV 突变体。 ATG4B 的蛋白水解活性是 LC3 裂解所必需的，从而启动膜接合。令人惊讶的是，与对照菌株相比，感染 BAD-ATG4BC74A 的细胞中基因组复制和病毒释放均增强。这些结果表明，自噬在 HCMV 感染期间作为抗病毒过程发挥作用，但对于二次 HCMV 颗粒包膜来说是可有可无的。缩写：ATG：自噬相关； BAC：细菌人工染色体； BECN1: 贝克林 1; CPE：细胞病变效应； cVAC：细胞质病毒组装区室； d.p.i.：感染后天数； DB：致密体； EBV：爱泼斯坦-巴尔病毒； galK：半乳糖激酶； HCMV：人类巨细胞病毒； HFF：人包皮成纤维细胞； IE：立即早期； IRS：内部重复短路； LC3：MAP1LC3A/B；单位：感染复数； MCP：主要衣壳蛋白； Pp：磷蛋白； sCP/UL48a：最小的衣壳蛋白； TRS：终端重复短； UL：独特长；美国：独特的短片
ABSTRACT Viral infections are often accompanied by the induction of autophagy as an intrinsic cellular defense mechanism. Herpesviruses have developed strategies to evade autophagic degradation and to manipulate autophagy of the host cells to their benefit. Here we addressed the role of macroautophagy/autophagy in human cytomegalovirus replication and for particle morphogenesis. We found that proteins of the autophagy machinery localize to cytoplasmic viral assembly compartments and enveloped virions in the cytoplasm. Surprisingly, the autophagy receptor SQSTM1/p62 was also found to colocalize with HCMV capsids in the nucleus of infected cells. This finding indicates that the autophagy machinery interacts with HCMV already at the early nuclear stages of particle morphogenesis. The membrane-bound form of LC3 and several autophagy receptors were packaged into extracellular HCMV virions. This suggested that autophagic membranes were included during secondary envelopment of HCMV virions. To further address the importance of autophagy in HCMV infection, we generated an HCMV mutant that expressed a dominant-negative version of the protease ATG4B (BAD-ATG4BC74A). The proteolytic activity of ATG4B is required for LC3 cleavage, priming it for membrane conjugation. Surprisingly, both genome replication and virus release were enhanced in cells infected with BAD-ATG4BC74A, compared to control strains. These results show that autophagy operates as an antiviral process during HCMV infection but is dispensable for secondary HCMV particle envelopment. Abbreviations: ATG: autophagy-related; BAC: bacterial artificial chromosome; BECN1: beclin 1; CPE: cytopathic effect; cVACs: cytoplasmic viral assembly compartments; d.p.i.: days post-infection; DB: dense body; EBV: Epstein-Barr virus; galK: galactokinase; HCMV: human cytomegalovirus; HFF: human foreskin fibroblasts; IE: immediate-early; IRS: internal repeat short; LC3: MAP1LC3A/B; m.o.i.; multiplicity of infection; MCP: major capsid protein; Pp: phosphoprotein; sCP/UL48a: smallest capsid protein; TRS: terminal repeat short; UL: unique long; US: unique short