The crystal structure of the influenza matrix protein M1 at neutral pH: M1-M1 protein interfaces can rotate in the oligomeric structures of M1
The crystal structure of the influenza matrix protein M1 at neutral pH: M1-M1 protein interfaces can rotate in the oligomeric structures of M1
复制标题
DOI：
10.1006/viro.2001.1119
复制
发表时间：
2001-10-10
期刊：
影响因子：
3.7
通讯作者：
Luo, M
中科院分区：
文献类型：
--
作者：
Harris, A;Forouhar, F;Luo, M
流感病毒基质蛋白（MI）在病毒膜下形成蛋白层，对病毒的稳定性和完整性至关重要。M1通过其膜和RNP结合活性介导病毒RNP进入病毒膜。为了理解M1-M1蛋白相互作用在形成M1层中的作用，在中性pH下对M1片段（1-162）进行X射线晶体学研究，并与酸性pH结构进行比较。在中性pH下，不对称单元是M1的堆叠二聚体。中性堆叠二聚体的长分子带通过平移形成，如由P1空间群所指示的。细长带在带的一侧上具有带正电荷的条纹。在酸性不对称单元中也发现了类似的M1-M1堆积界面。然而，在酸性堆叠的二聚体中，分子不是直的，而是通过稍微改变M1-M1堆叠界面而相对于彼此旋转。酸性结构具有额外的M1-M1双重界面。蛋白质对接证实了M1-M1的堆积和M1-M1的双重界面可以形成M1分子的双带。通过M1分子之间的旋转关系的迭代重复，产生M1的螺旋。这些研究表明，M1具有形成直的或弯曲的细长带和螺旋的能力。这些寡聚体与先前对M1的电子显微镜研究一致，该研究表明，当从流感病毒中似乎是M1的螺旋壳中分离时，分离的M1形成细长且柔性的条带。(C)北京：科学出版社.
The influenza matrix protein (MI) forms a protein layer under the viral membrane and is essential for viral stability and integrity. M1 mediates the encapsidation of the viral RNPs into the viral membrane by its membrane and RNP-binding activities. In order to understand the roles of MI-Ml protein interactions in forming the Mi layer, X-ray crystallographic studies of a M1 fragment (1-162) were carried out at neutral pH and compared with an acidic pH structure, At neutral pH the asymmetric unit was a stacked dimer of M1. A long molecular ribbon of neutral stacked dimers was formed by translation as dictated by the P1 space group. The elongated ribbon had a positively charged stripe on one side of the ribbon. A similar M1-M1 stacking interface was also found in the acidic asymmetric unit. However, within the acidic stacked dimer the molecules were not straight, but rotated in relation to each other by slightly changing the M1-M1 stacking interface. The acidic structure possessed an additional M1-M1 twofold interface. Protein docking confirmed that the M1-M1 stacking and M1-M1 twofold interfaces could be used to form a double ribbon of M1 molecules. By iterative repetition of the rotated relationship among the M1 molecules, a helix of M1 was generated. These studies suggest that M1 has the ability to form straight or bent elongated ribbons and helices. These oligomers are consistent with previous electron microscopic studies of M1, which demonstrated that isolated M1 formed elongated and flexible ribbons when isolated from what appeared to be a helical shell of M1 in the influenza virus. (C) 2001 Academic Press.