Role of the Arginine Cluster in the Disordered Domain of Herpes Simplex Virus 1 UL34 for the Recruitment of ESCRT-III for Viral Primary Envelopment
Role of the Arginine Cluster in the Disordered Domain of Herpes Simplex Virus 1 UL34 for the Recruitment of ESCRT-III for Viral Primary Envelopment
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DOI：
10.1128/jvi.01704-21
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发表时间：
2022-01-01
影响因子：
5.4
通讯作者：
Kawaguchi, Yasushi
中科院分区：
文献类型：
--
作者：
Arii, Jun;Takeshima, Kosuke;Kawaguchi, Yasushi
在疱疹病毒初生核衣壳的核输出过程中，核衣壳通过获得内核膜作为初级包膜（primary envelope）而出芽。我们最近报道了单纯疱疹病毒1 （HSV-1）核出口复合体（NEC），由UL34和UL31组成，与转运III （ESCRTIII）衔接体ALIX所需的内体分选复合体相互作用，并将ESCRT-III机制招募到INM以进行有效的初级包膜。在这项研究中，我们在hsv1感染细胞的UL34的无序结构域中发现了一个由6个精氨酸残基组成的簇，作为与ALIX相互作用以及ALIX和ESCRT-III蛋白CHMP4B募集到INM所需的最小区域。精氨酸簇的突变表现出与先前报道的ESCRT-III抑制相似的表型，包括NEC的错误定位，诱导含有包膜病毒粒子的膜内陷结构，包膜病毒粒子在内陷和核周空间异常积聚，以及病毒复制减少。我们还发现UL34中的精氨酸簇对HSV-1复制的影响主要依赖于ALIX。这些结果表明，UL34无序结构域中的精氨酸簇是与ALIX相互作用和向INM募集ESCRT-III机制以促进初级包膜所必需的。疱疹病毒UL34同源物含有保守的氨基末端结构域，在初级包膜过程中通过与UL31同源物的相互作用介导囊泡形成。UL34同源物还包括与其膜锚定区相邻的其他结构域，这些结构域长度不同，在疱疹病毒中是可变的，并且不形成区分的二级结构。然而，这些紊乱结构域在感染细胞中的作用仍有待阐明。在这项研究中，我们提供的数据表明，HSV-1 UL34无序结构域中的精氨酸簇介导了与ALIX的相互作用，从而导致ESCRT-III机制被募集到INM中以实现有效的初级包膜。这是首次报道UL34同源物的无序结构域在疱疹病毒感染中的作用的研究。
During the nuclear export of nascent nucleocapsids of herpesviruses, the nucleocapsids bud through the inner nuclear membrane (INM) by acquiring the INM as a primary envelope (primary envelopment). We recently reported that herpes simplex virus 1 (HSV-1) nuclear egress complex (NEC), which consists of UL34 and UL31, interacts with an endosomal sorting complex required for transport III (ESCRTIII) adaptor ALIX and recruits ESCRT-III machinery to the INM for efficient primary envelopment. In this study, we identified a cluster of six arginine residues in the disordered domain of UL34 as a minimal region required for the interaction with ALIX, as well as the recruitment of ALIX and an ESCRT-III protein CHMP4B to the INM in HSV1-infected cells. Mutations in the arginine cluster exhibited phenotypes similar to those with ESCRT-III inhibition reported previously, including the mislocalization of NEC, induction of membranous invagination structures containing enveloped virions, aberrant accumulation of enveloped virions in the invaginations and perinuclear space, and reduction of viral replication. We also showed that the effect of the arginine cluster in UL34 on HSV-1 replication was dependent primarily on ALIX. These results indicated that the arginine cluster in the disordered domain of UL34 was required for the interaction with ALIX and the recruitment of ESCRT-III machinery to the INM to promote primary envelopment.IMPORTANCE Herpesvirus UL34 homologs contain conserved amino-terminal domains that mediate vesicle formation through interactions with UL31 homologs during primary envelopment. UL34 homologs also comprise other domains adjacent to their membrane anchoring regions, which differ in length, are variable in herpesviruses, and do not form distinguished secondary structures. However, the role of these disordered domains in infected cells remains to be elucidated. In this study, we present data suggesting that the arginine cluster in the disordered domain of HSV-1 UL34 mediates the interaction with ALIX, thereby leading to the recruitment of ESCRT-III machinery to the INM for efficient primary envelopment. This is the first study to report the role of the disordered domain of a UL34 homolog in herpesvirus infections.