Functional implications of quasi-equivalence in a T = 3 icosahedral animal virus established by cryo-electron microscopy and X-ray crystallography.
Functional implications of quasi-equivalence in a T = 3 icosahedral animal virus established by cryo-electron microscopy and X-ray crystallography.
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通过冷冻电子显微镜和 X 射线晶体学建立的 T = 3 二十面体动物病毒的准等效性的功能意义。
DOI：
10.1016/s0969-2126(00)00029-0
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发表时间：
1994
期刊：
影响因子：
--
通讯作者：
Johnson,JE
中科院分区：
文献类型：
--
作者：
Cheng,RH;Reddy,VS;Olson,NH;Fisher,AJ;Baker,TS;Johnson,JE
背景对简单RNA动物病毒的研究表明，细胞附着、颗粒失稳和细胞进入是复杂的过程，需要一定程度的衣壳复杂，而仅包含单一基因产物的外壳很难实现这一点。诺达病毒[如鸡舍病毒(FHV)]是个例外。我们以前已经在3？分辨率下确定了FHV的结构，现在将这一信息与冷冻电子显微镜的数据相结合，试图阐明诺达病毒感染动物细胞的过程。结果计算出了差值图，其中从FHV衣壳蛋白的3.0？分辨率X射线模型中减去了22？分辨率的电子密度，该电子密度是从22？分辨率的FHV的冷冻电子显微镜重建得到的。将该密度与X射线模型进行比较，结果表明，相同多肽序列的准等效区与本体RNA密度的相互作用明显不同。以前报道的颗粒成熟的双相动力学和亚基切割对颗粒感染性的要求与这些结果一致。结论在本研究的基础上，我们提出了一个概念上类似于脊髓灰质炎病毒的NODAV感染模型，但在细节上不同。衣壳中单一蛋白质类型的限制导致了值得注意的准对称性的使用，不仅控制“口袋因子”的结合，而且还调节成熟切割和释放可能进一步与细胞膜相互作用的五聚体螺旋束(附在基因组RNA上)。
BackgroundStudies of simple RNA animal viruses show that cell attachment, particle destabilization and cell entry are complex processes requiring a level of capsid sophistication that is difficult to achieve with a shell containing only a single gene product. Nodaviruses [such as Flock House virus (FHV)] are an exception. We have previously determined the structure of FHV at 3 å resolution, and now combine this information with data from cryo-electron microscopy in an attempt to clarify the process by which nodaviruses infect animal cells.ResultsA difference map was computed in which electron density at 22 å resolution, derived from the 3.0 å resolution X-ray model of the FHV capsid protein, was subtracted from the electron density derived from the cryo-electron microscopy reconstruction of FHV at 22 å resolution. Comparisons of this density with the X-ray model showed that quasi-equivalent regions of identical polypeptide sequences have markedly different interactions with the bulk RNA density. Previously reported biphasic kinetics of particle maturation and the requirement of subunit cleavage for particle infectivity are consistent with these results.ConclusionsOn the basis of this study we propose a model for nodavirus infection that is conceptually similar to that proposed for poliovirus but differs from it in detail. The constraints of a single protein type in the capsid lead to a noteworthy use of quasi-symmetry not only to control the binding of a ‘pocket factor' but also to modulate maturation cleavage and to release a pentameric helical bundle (with genomic RNA attached) that may further interact with the cell membrane.
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影响因子：
3.4
作者：
BAKER, TS;NEWCOMB, WW;BROWN, JC
通讯作者：
BROWN, JC
DOI：
10.1016/s0021-9258(17)36883-7
发表时间：
1994-05
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
A. Zlotnick;V. Reddy;R. Dasgupta;A. Schneemann;W. Ray;R. Rueckert;J. Johnson
通讯作者：
A. Zlotnick;V. Reddy;R. Dasgupta;A. Schneemann;W. Ray;R. Rueckert;J. Johnson
DOI：
10.1073/pnas.90.2.507
发表时间：
1993-01-15
影响因子：
11.1
作者：
OLSON, NH;KOLATKAR, PR;ROSSMANN, MG
通讯作者：
ROSSMANN, MG
可溶性细胞受体介导的脊髓灰质炎病毒构象改变的表征。
影响因子：
3.7
作者：
GómezYafal,A;Kaplan,G;Racaniello,VR;Hogle,JM
通讯作者：
Hogle,JM
DOI：
10.1073/pnas.83.1.63
发表时间：
1986-01-01
影响因子：
11.1
作者：
DASMAHAPATRA, B;DASGUPTA, R;KAESBERG, P
通讯作者：
KAESBERG, P