Visualization of Rad54, a chromatin remodeling protein, translocating on single DNA molecules
Visualization of Rad54, a chromatin remodeling protein, translocating on single DNA molecules
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DOI：
10.1016/j.molcel.2006.05.009
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发表时间：
2006-07-07
期刊：
影响因子：
16
通讯作者：
Kowalczykowski, Stephen C.
中科院分区：
文献类型：
--
作者：
Amitani, Ichiro;Baskin, Ronald J.;Kowalczykowski, Stephen C.
Rad54 蛋白在双链 DNA (dsDNA) 断裂的重组修复中发挥着重要作用。它是一种 dsDNA 依赖性 ATP 酶，属于染色质重塑蛋白 Swi2/Snf2 家族。 Rad54 重塑 (1) DNA 结构、(2) 染色质结构和 (3) Rad51-dsDNA 复合物。这些能力意味着 Rad54 沿着 DNA 移动。在这里，我们通过观察 Rad54 沿单链 DNA 分子的运动来提供 Rad54 易位的直接证据。与重塑过程相比，易位出乎意料地快速，在 25 摄氏度下以 301 +/- 22 bp/s 的速度发生。Rad54 沿着 dsDNA 随机结合，并以取决于 ATP 浓度的速度沿两个可能的方向之一移动 (K-m = 97 +/- 28 mu M)。运动的持续性也令人惊讶：平均移动距离约为 11,500 bp，分子在停止前移动高达 32,000 bp。讨论了 Rad54 易位酶活性在染色质和蛋白质-DNA 复合物重塑中的机制意义。Rad54 蛋白在双链 DNA (dsDNA) 断裂的重组修复中发挥着重要作用。它是一种 dsDNA 依赖性 ATP 酶，属于染色质重塑蛋白 Swi2/Snf2 家族。 Rad54 重塑 (1) DNA 结构、(2) 染色质结构和 (3) Rad51-dsDNA 复合物。这些能力意味着 Rad54 沿着 DNA 移动。在这里，我们通过观察 Rad54 沿单链 DNA 分子的运动来提供 Rad54 易位的直接证据。与重塑过程相比，易位出乎意料地快速，在 25 摄氏度下以 301 +/- 22 bp/s 的速度发生。Rad54 沿着 dsDNA 随机结合，并以取决于 ATP 浓度的速度沿两个可能的方向之一移动 (K-m = 97 +/- 28 mu M)。运动的持续性也令人惊讶：平均移动距离约为 11,500 bp，分子在停止前移动高达 32,000 bp。讨论了 Rad54 易位酶活性在染色质和蛋白质-DNA 复合物重塑中的机制意义。
Rad54 protein plays an important role in the recombinational repair of double-strand DNA (dsDNA) breaks. It is a dsDNA-dependent ATPase that belongs to the Swi2/Snf2 family of chromatin-remodeling proteins. Rad54 remodels (1) DNA structure, (2) chromatin structure, and (3) Rad51-dsDNA complexes. These abilities imply that Rad54 moves along DNA. Here, we provide direct evidence of Rad54 translocation by visualizing its movement along single molecules of dsDNA. When compared to the remodeling processes, translocation is unexpectedly rapid, occurring at 301 +/- 22 bp/s at 25 degrees C. Rad54 binds randomly along the dsDNA and moves in either of the two possible directions with a velocity dependent on ATP concentration (K-m = 97 +/- 28 mu M). Movement is also surprisingly processive: the average distance traveled is similar to 11,500 bp, with molecules traversing up to 32,000 bp before stopping. The mechanistic implications of this vigorous Rad54 translocase activity in chromatin and protein-DNA complex remodeling are discussed.Rad54 protein plays an important role in the recombinational repair of double-strand DNA (dsDNA) breaks. It is a dsDNA-dependent ATPase that belongs to the Swi2/Snf2 family of chromatin-remodeling proteins. Rad54 remodels (1) DNA structure, (2) chromatin structure, and (3) Rad51-dsDNA complexes. These abilities imply that Rad54 moves along DNA. Here, we provide direct evidence of Rad54 translocation by visualizing its movement along single molecules of dsDNA. When compared to the remodeling processes, translocation is unexpectedly rapid, occurring at 301 +/- 22 bp/s at 25 degrees C. Rad54 binds randomly along the dsDNA and moves in either of the two possible directions with a velocity dependent on ATP concentration (K-m = 97 +/- 28 mu M). Movement is also surprisingly processive: the average distance traveled is similar to 11,500 bp, with molecules traversing up to 32,000 bp before stopping. The mechanistic implications of this vigorous Rad54 translocase activity in chromatin and protein-DNA complex remodeling are discussed.