Mechanisms of DNA Packaging by Large Double-Stranded DNA Viruses.
Mechanisms of DNA Packaging by Large Double-Stranded DNA Viruses.
复制标题
DOI：
10.1146/annurev-virology-100114-055212
复制
发表时间：
2015-11
影响因子：
11.3
通讯作者：
Feiss M
中科院分区：
文献类型：
--
作者：
Rao VB;Feiss M
病毒双链DNA（dsDNA）移位到二十面体前头壳中是由TerL催化的，TerL是一种具有ATP酶、内切核酸酶和移位酶活性的马达蛋白。TerL在由TerS识别的未成熟病毒DNA多联体的核酸内切酶切割后，在prohead的门户顶点组装成五聚环马达，并使用ATP水解能量进行DNA易位。TerL的N-末端ATP酶通过铰链连接到C-末端核酸内切酶。尺蠖模型提出，适度的域运动伴随ATP水解被放大，通过静电相互作用的变化，到结合到DNA的C-末端域的更大的运动。在噬菌体φ29中，五个TerL亚基中的四个依次水解ATP，每个驱动2.5bp的易位。在一个病毒基因组被包裹后，内部压力发出信号，终止包装并排出马达。目前的重点是包装复合物的结构和TerL在DNA包装，核酸内切酶调节和电机力学的动力学。
Translocation of viral double-stranded DNA (dsDNA) into the icosahedral prohead shell is catalyzed by TerL, a motor protein that has ATPase, endonuclease, and translocase activities. TerL, following endonucleolytic cleavage of immature viral DNA concatemer recognized by TerS, assembles into a pentameric ring motor on the prohead’s portal vertex and uses ATP hydrolysis energy for DNA translocation. TerL’s N-terminal ATPase is connected by a hinge to the C-terminal endonuclease. Inchworm models propose that modest domain motions accompanying ATP hydrolysis are amplified, through changes in electrostatic interactions, into larger movements of the C-terminal domain bound to DNA. In phage φ29, four of the five TerL subunits sequentially hydrolyze ATP, each powering translocation of 2.5 bp. After one viral genome is encapsidated, the internal pressure signals termination of packaging and ejection of the motor. Current focus is on the structures of packaging complexes and the dynamics of TerL during DNA packaging, endonuclease regulation, and motor mechanics.