Lac repressor hinge flexibility and DNA looping: single molecule kinetics by tethered particle motion.
Lac repressor hinge flexibility and DNA looping: single molecule kinetics by tethered particle motion.
复制标题
LAC阻遏铰链柔韧性和DNA循环：通过束缚颗粒运动的单分子动力学。
DOI：
10.1093/nar/gkl393
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发表时间：
2006
影响因子：
14.9
通讯作者：
Pavone, Francesco Saverio
中科院分区：
文献类型：
--
作者：
Vanzi, Francesco;Broggio, Chiara;Sacconi, Leonardo;Pavone, Francesco Saverio
拴系粒子运动(TPM)可以在单分子水平上直接检测各种生物分子的活性。它最先是RNA聚合酶的先驱，最近也被应用于其他酶。在这项工作中，我们使用TPM系统地研究了野生型Lac抑制子(wt-Laci)和铰链突变体Q60G和Q60+1的DNA环化动力学。我们实现了一种新的TPM数据分析方法，以可靠地测量环形成和破坏的动力学，并量化蛋白质铰链柔性和DNA环应变对这种动力学的影响。我们证明了蛋白质铰链的灵活性对环态的寿命有深远的影响。我们的测量还表明，DNA弯曲能对环破裂动力学的影响不大，而对环形成动力学的影响很大。这些观察结果证实了越来越多的理论研究，这些研究旨在表征DNA柔性、拉伸和扭转对蛋白质结合和解离动力学的影响，强化了体内这些机械因素可能在基因表达调控中发挥重要作用的想法。
The tethered particle motion (TPM) allows the direct detection of activity of a variety of biomolecules at the single molecule level. First pioneered for RNA polymerase, it has recently been applied also to other enzymes. In this work we employ TPM for a systematic investigation of the kinetics of DNA looping by wild-type Lac repressor (wt-LacI) and by hinge mutants Q60G and Q60 + 1. We implement a novel method for TPM data analysis to reliably measure the kinetics of loop formation and disruption and to quantify the effects of the protein hinge flexibility and of DNA loop strain on such kinetics. We demonstrate that the flexibility of the protein hinge has a profound effect on the lifetime of the looped state. Our measurements also show that the DNA bending energy plays a minor role on loop disruption kinetics, while a strong effect is seen on the kinetics of loop formation. These observations substantiate the growing number of theoretical studies aimed at characterizing the effects of DNA flexibility, tension and torsion on the kinetics of protein binding and dissociation, strengthening the idea that these mechanical factors in vivo may play an important role in the modulation of gene expression regulation.
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影响因子：
4.4
作者：
JACOBSON, H;STOCKMAYER, WH
通讯作者：
STOCKMAYER, WH
影响因子：
2.5
作者：
Capitanio, M;Vanzi, F;Pavone, FS
通讯作者：
Pavone, FS
DOI：
10.1073/pnas.2034851100
发表时间：
2003-09-30
影响因子：
11.1
作者：
Lia, G;Bensimon, D;Finzi, L
通讯作者：
Finzi, L
影响因子：
64.8
作者：
FINER, JT;SIMMONS, RM;SPUDICH, JA
通讯作者：
SPUDICH, JA
影响因子：
64.8
作者：
ASHKIN, A;SCHUTZE, K;SCHLIWA, M
通讯作者：
SCHLIWA, M