Role of φ29 connector channel loops in late-stage DNA packaging.
Role of φ29 connector channel loops in late-stage DNA packaging.
复制标题
DOI：
10.1016/j.jmb.2011.04.070
复制
发表时间：
2011-07-01
影响因子：
5.6
通讯作者：
Jardine PJ
中科院分区：
文献类型：
--
作者：
Grimes S;Ma S;Gao J;Atz R;Jardine PJ
双链 DNA 噬菌体及其真核病毒对应物具有嵌入独特衣壳顶点的 12 重头尾连接器组合。该顶点是 DNA 包装马达的组装部位，连接器有一个中心通道，病毒 DNA 在基因组包装和随后的宿主感染过程中通过该通道。来自不同噬菌体的连接器的晶体结构揭示了投射到连接器通道中的无序残基或结构化环。鉴于与易位 DNA 底物的接近，这些环被认为在 DNA 包装中发挥作用。先前的模型提出包装 ATP 酶或连接器通道环中的结构运动作为将 DNA 易位到前头的驱动力。在这里，我们突变了枯草芽孢杆菌噬菌体 φ29 连接器的通道环，并表明这些环在 DNA 易位中没有积极作用。相反，它们似乎在包装接近尾声时具有重要功能，将包装的 DNA 保留在头部，为运动分离以及随后的尾部组装和病毒体完成做好准备。
Double-stranded DNA bacteriophages and their eukaryotic virus counterparts have twelve-fold head-tail connector assemblages embedded at a unique capsid vertex. This vertex is the site of assembly of the DNA packaging motor, and the connector has a central channel through which viral DNA passes during genome packaging and subsequent host infection. Crystal structures of connectors from different phages reveal either disordered residues or structured loops that project into the connector channel. Given the proximity to the translocating DNA substrate, these loops have been proposed to play a role in DNA packaging. Previous models have proposed structural motions in either the packaging ATPase or the connector channel loops as the driving force that translocates the DNA into the prohead. Here we mutate the channel loops of the Bacillus subtilis bacteriophage φ29 connector and show that these loops have no active role in translocation of DNA. Instead, they appear to have an essential function near the end of packaging, acting to retain the packaged DNA in the head in preparation for motor detachment and subsequent tail assembly and virion completion.
登录
查看更多内容
影响因子：
56.9
作者：
GUO, PX;ERICKSON, S;ANDERSON, D
通讯作者：
ANDERSON, D
影响因子：
3.7
作者：
Isidro, A;Henriques, AO;Tavares, P
通讯作者：
Tavares, P
影响因子：
11.4
作者：
Orlova, EV;Gowen, B;Tavares, P
通讯作者：
Tavares, P
影响因子：
16
作者：
Morais, MC;Choi, KH;Rossmann, MG
通讯作者：
Rossmann, MG
影响因子：
3
作者：
BROOKS, BR;BRUCCOLERI, RE;KARPLUS, M
通讯作者：
KARPLUS, M