Cryo-EM maps reveal five-fold channel structures and their modification by gatekeeper mutations in the parvovirus minute virus of mice (MVM) capsid.
Cryo-EM maps reveal five-fold channel structures and their modification by gatekeeper mutations in the parvovirus minute virus of mice (MVM) capsid.
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冷冻电镜图揭示了小鼠细小病毒 (MVM) 衣壳中的五重通道结构及其看门突变的修饰。
DOI：
10.1016/j.virol.2017.07.015
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发表时间：
2017
期刊：
影响因子：
3.7
通讯作者：
Hafenstein,Susan
中科院分区：
文献类型：
--
作者：
Subramanian,Suriyasri;Organtini,LindseyJ;Grossman,Alec;Domeier,PhillipP;Cifuente,JavierO;Makhov,AlexanderM;Conway,JamesF;D'AbramoJr,Anthony;Cotmore,SusanF;Tattersall,Peter;Hafenstein,Susan
在小鼠微小病毒（MVM）衣壳中，二十面体五重通道作为门户介导基因组包装、基因组释放和病毒肽的阶段性挤出。先前的研究表明，残基L172和V40是通道功能所必需的。MVMi野生型和突变体L172 T和V40 A病毒样颗粒（VLP）的结构从冷冻-EM数据解析。在野生型颗粒的通道中观察到两个收缩点，称为中间门和内门，分别涉及残基L172和V40。虽然V40 A VLP的中门似乎正常，但在L172 T中，相邻的通道壁发生了改变，并且在两种突变体中，内门都发生了重大破坏，这表明直接的L172：V40键合对其结构完整性至关重要。在野生型颗粒中，来自VP 2 N末端的残基映射到位于通道开口下方的爪状密度，这些密度在突变体中变得无序，表明L172和V40都参与了VP 2 N末端的组织。
In minute virus of mice (MVM) capsids, icosahedral five-fold channels serve as portals mediating genome packaging, genome release, and the phased extrusion of viral peptides. Previous studies suggest that residues L172 and V40 are essential for channel function. The structures of MVMi wildtype, and mutant L172T and V40A virus-like particles (VLPs) were solved from cryo-EM data. Two constriction points, termed the mid-gate and inner-gate, were observed in the channels of wildtype particles, involving residues L172 and V40 respectively. While the mid-gate of V40A VLPs appeared normal, in L172T adjacent channel walls were altered, and in both mutants there was major disruption of the inner-gate, demonstrating that direct L172:V40 bonding is essential for its structural integrity. In wildtype particles, residues from the N-termini of VP2 map into claw-like densities positioned below the channel opening, which become disordered in the mutants, implicating both L172 and V40 in the organization of VP2 N-termini.