Virus-specific interaction between the human cytomegalovirus major capsid protein and the C terminus of the assembly protein precursor
Virus-specific interaction between the human cytomegalovirus major capsid protein and the C terminus of the assembly protein precursor
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DOI：
10.1128/jvi.70.11.8081-8088.1996
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发表时间：
1996-11-01
影响因子：
5.4
通讯作者：
Hong, Z
中科院分区：
文献类型：
--
作者：
BeaudetMiller, M;Zhang, RM;Hong, Z
我们以前确定了一个最小的12个氨基酸的结构域在C末端的单纯疱疹病毒1型（HSV-1）的支架蛋白，这是需要与HSV-1的主要衣壳蛋白的相互作用。相互作用需要使最小结构域的疏水性最大化的α-螺旋结构。为了解决巨细胞病毒（CMV）是否利用相同的策略进行衣壳组装，从细菌细胞中产生并纯化几种谷胱甘肽S-转移酶融合蛋白至CMV组装蛋白前体的C末端。该研究搁置了在C末端附近含有16个氨基酸的谷胱甘肽S-转移酶融合物足以与主要衣壳蛋白相互作用。有趣的是，没有检测到HSV-1和CMV之间的交叉相互作用。突变分析表明，在CMV相互作用结构域的中心苯丙氨酸残基的N-末端侧的三个氨基酸区域在确定相互作用的病毒特异性中发挥了作用。当该区域被转化以对应于HSV-1的区域时，CMV装配蛋白结构域失去了其与CMV主要衣壳蛋白相互作用的能力，但获得了与HSV-1主要衣壳蛋白的完全相互作用。为了解决CMV组装蛋白的最小相互作用结构域是否形成与HSV-1中的α-螺旋结构类似的α-螺旋结构，进行了肽竞争实验。结果表明，衍生自具有受约束的α-螺旋结构的相互作用结构域的环状肽比不受约束的线性肽更有效地竞争与主要衣壳蛋白的相互作用。相比之下，含有Ala取代关键苯丙氨酸残基的环肽根本不竞争相互作用。本研究的结果表明：（i）CMV可能已经开发出一种与HSV-1相似的衣壳组装策略;（ii）CMV组装蛋白中的最小相互作用基序需要α-螺旋与主要衣壳蛋白有效相互作用;（iii）CMV最小相互作用结构域中的Phe残基对于与主要衣壳蛋白的相互作用至关重要。
We previously identified a minimal 12-amino-acid domain in the C terminus of the herpes simplex virus type 1 (HSV-1) scaffolding protein which is required for interaction with the HSV-1 major capsid protein. An alpha-helical structure which maximizes the hydropathicity of the minimal domain is required for the interaction. To address whether cytomegalovirus (CMV) utilizes the same strategy for capsid assembly, several glutathione S-transferase fusion proteins to the C terminus of the CMV assembly protein precursor were produced and purified from bacterial cells. The study shelved that the glutathione S-transferase fusion containing 16 amino acids near the C-terminal end was sufficient to interact with the major capsid protein. Interestingly, no cross-interaction between HSV-1 and CMV could be detected. Mutation analysis revealed that a three-aminoacid region at the N-terminal side of the central Phe residue of the CMV interaction domain played a role in determining the viral specificity of the interaction. When this region was converted so as to correspond to that of HSV-1, the CMV assembly protein domain lost its ability to interact with the CMV major capsid protein but gained full interaction with the HSV-1 major capsid protein. To address whether the minimal interaction domain of the CMV assembly protein forms an alpha-helical structure similar to that in HSV-1, peptide competition experiments were carried out. The results showed that a cyclic peptide derived from the interaction domain with a constrained alpha-helical structure competed for interaction with the major capsid protein much more efficiently than the unconstrained linear peptide. In contrast, a cyclic peptide containing an Ala substitution for the critical Phe residue did not compete for the interaction at all. The results of this study suggest that (i) CMV may have developed a strategy similar to that of HSV-1 for capsid assembly; (ii) the minimal interaction motif in the CMV assembly protein requires an alpha-helix for efficient interaction with the major capsid protein; and (iii) the Phe residue in the CMV minimal interaction domain is critical for interaction with the major capsid protein.