Functional implications of the structure of the murine parvovirus, minute virus of mice
Functional implications of the structure of the murine parvovirus, minute virus of mice
复制标题
DOI：
10.1016/s0969-2126(98)00137-3
复制
发表时间：
1998-11-15
期刊：
影响因子：
--
通讯作者：
Rossmann, MG
中科院分区：
文献类型：
--
作者：
Agbandje-McKenna, M;Llamas-Saiz, AL;Rossmann, MG
背景资料：小鼠细小病毒（MVM）是一种含有单链（ss）DNA的鼠细小病毒，衣壳由60条二十面体相关的多肽链组成，每条多肽链由两种结构蛋白VP 1和VP 2共有的C-末端区域组成。在感染性病毒体中，大多数VP 2分子通过从N末端去除约20个氨基酸而裂解为VP 3。在VP 2的587个氨基酸中，大约一半与抗原性不同的犬细小病毒（CPV）的类似衣壳蛋白中的氨基酸相同，其晶体结构先前已被确定。（MVM的免疫抑制菌株）先前报道为3.5埃分辨率。我们在这里报告的MVMi病毒结构的分析，并提供深入了解组织嗜性，抗原性和DNA包装。氨基酸决定MVM组织嗜性被发现集群上，或附近，病毒表面。一个保守的，富含甘氨酸的，N-末端肽被认为是运行通过一个圆柱形通道沿着每个五倍轴，并可能具有抗原性的影响。密度内的病毒粒子被解释为29 ssDNA核苷酸每二十面体不对称单位，并占超过三分之一的病毒genome.Conclusions：在MVMi的五倍通道中的甘氨酸丰富的序列的存在下提供了一种可能的机制来解释如何独特的N-末端区域的VP 1成为externalized在感染性细小病毒粒子。决定向性的残基可以形成调节组织特异性的次级宿主细胞因子的附着识别位点。CPV和MVMi衣壳内表面相似区域的核苷酸排序表明细小病毒衣壳内存在基因组DNA识别位点。
Background: Minute virus of mice (MVM) is a single-stranded (ss) DNA-containing, murine parvovirus with a capsid built up of 60 icosahedrally related polypeptide chains, each of which consists of the C-terminal region common to two structural proteins, VP1 and VP2. In infectious virions, most VP2 molecules are cleaved to VP3 by the removal of about 20 amino acids from the N terminus. Of the 587 amino acids in VP2, approximately half are identical to those in the analogous capsid protein of the antigenically distinct canine parvovirus (CPV), the crystal structure of which has previously been determined, The three-dimensional structure determination of MVMi (the immunosuppressive strain of MVM) was previously reported to 3.5 Angstrom resolution.Results: We report here an analysis of the MVMi virus structure and provide insights into tissue tropism, antigenicity and DNA packaging. Amino acids determining MVM tissue tropism were found to cluster on, or near, the viral surface. A conserved, glycine-rich, N-terminal peptide was seen to run through a cylindrical channel along each fivefold axis and may have implications for antigenicity. Density within the virion was interpreted as 29 ssDNA nucleotides per icosahedral asymmetric unit, and accounts for over one-third of the viral genome.Conclusions: The presence of the glycine-rich sequence in the fivefold channels of MVMi provides a possible mechanism to explain how the unique N-terminal region of VP1 becomes externalized in infectious parvovirions. Residues that determine tropism may form an attachment recognition site for a secondary host-cell factor that modulates tissue specificity. The ordering of nucleotides in a similar region of the interior surface in the CPV and MVMi capsids suggests the existence of a genomic DNA-recognition site within the parvoviral capsid.