STRUCTURE OF THE TOP A-T COMPONENT OF ALFALFA MOSAIC-VIRUS - A NON-ICOSAHEDRAL VIRION
STRUCTURE OF THE TOP A-T COMPONENT OF ALFALFA MOSAIC-VIRUS - A NON-ICOSAHEDRAL VIRION
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DOI：
10.1016/s0022-2836(83)80350-7
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发表时间：
1983-01-01
影响因子：
5.6
通讯作者：
MELLEMA, JE
中科院分区：
文献类型：
--
作者：
CUSACK, S;OOSTERGETEL, GT;MELLEMA, JE
利用中子散射、准弹性光散射和电子显微镜，建立了苜蓿花叶病毒（AMV-Ta-t） Top a-t[腺嘌呤-胸腺嘧啶]成分衣壳结构模型。在EM中，AMV-Ta-t表现为不规则的椭球状粒子，表观尺寸为275（±）。31)；225(+ -。22) .ANG . .假设粒子是单分散的，模型计算表明，中子散射数据最好的解释是，病毒粒子的外维为284.4倍的扁椭球体形状。[au:]216年.ANG . .基于这一结果，并结合已知的病毒粒子组成，提出衣壳结构可能基于具有52个点群对称的三角面体，由120个亚基组成。这样的模型将意味着与二十面体衣壳中通常必要的等效亚基相互作用有更大的偏差。然而，中子和光子的相关数据不排除Top a-t是不规则长形的稍微多分散的可能性，其平均尺寸为31.2倍。232 .次。232年.ANG . .这两种可能性都支持苜蓿花叶病毒外壳蛋白能够广泛的亚基间相互作用的概念，这种灵活性导致衣壳结构的相当多态。
Neutron-scattering in combination with quasi-elastic light-scattering and EM was used to derive a model for the capsid structure of the Top a-t [adenine-thymine] component of alfalfa mosaic virus (AMV-Ta-t). In the EM, AMV-Ta-t appears as an irregular ellipsoidal particle with apparent dimensions 275(.+-. 31) .ANG. .RTM. 225(.+-. 22) .ANG.. Assuming that the particles are monodisperse, model calculations show that the neutron-scattering data are best explained by an oblate ellipsoidal shape for the virion with external dimensions 284 .ANG. .times. 284 .ANG. .RTM. 216 .ANG.. Based on this result, and in combination with the known composition of the virion, it is suggested that the capsid structure could be based on a deltahedron with 52 pointgroup symmetry and comprising 120 subunits. Such a model would imply a greater deviation from equivalent subunit interactions than normally necessary in icosahedral capsids. The neutron and photon correlation data, however, do not rule out the possibility that Top a-t is a slightly polydisperse preparation of irregular prolate shapes with mean dimensions 312 .ANG. .times. 232 .ANG. .times. 232 .ANG.. Both possibilities support the concept of alfalfa mosaic virus coat protein being capable of a wide range of intersubunit interactions, this flexibility resulting in considerable polymorphism in capsid structures.