How a protein searches for its specific site on DNA: The role of intersegment transfer
How a protein searches for its specific site on DNA: The role of intersegment transfer
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DOI：
10.1103/physreve.76.051909
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发表时间：
2007-11-01
影响因子：
2.4
通讯作者：
Shklovskii, B. I.
中科院分区：
文献类型：
--
作者：
Hu, Tao;Shklovskii, B. I.
众所周知，蛋白质在DNA上定位特定靶点的速度比Smoluchowski三维扩散速度预测的快两个数量级。解决这种差异的机制之一被称为“节段间转移”。许多蛋白质有两个DNA结合位点，可以从一个DNA片段转移到另一个片段，而不会解离到水中。我们计算了这类蛋白质在致密的球状DNA中的目标搜索率，同时考虑了片段间转移与DNA运动和蛋白质沿DNA的滑动。我们发现，在蛋白质大部分时间吸附在DNA上的情况下，片段间转移起着非常重要的作用。
Proteins are known to locate their specific targets on DNA up to two orders of magnitude faster than predicted by the Smoluchowski three-dimensional diffusion rate. One of the mechanisms proposed to resolve this discrepancy is termed "intersegment transfer." Many proteins have two DNA binding sites and can transfer from one DNA segment to another without dissociation to water. We calculate the target search rate for such proteins in a dense globular DNA, taking into account intersegment transfer working in conjunction with DNA motion and protein sliding along DNA. We show that intersegment transfer plays a very important role in cases where the protein spends most of its time adsorbed on DNA.