Changes in DNA bending and flexing due to tethered cations detected by fluorescence resonance energy transfer.
Changes in DNA bending and flexing due to tethered cations detected by fluorescence resonance energy transfer.
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DOI：
10.1093/nar/gkj498
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发表时间：
2006
影响因子：
14.9
通讯作者：
Parkhurst LJ
中科院分区：
文献类型：
--
作者：
Williams SL;Parkhurst LK;Parkhurst LJ
局部DNA变形是由序列相关的碱基堆积、链内磷酸盐排斥、反离子和水分布之间的相互作用引起的，而蛋白质的接近和结合使其进一步复杂化。静电在这个复杂的化学作用进行了研究，使用拴系的阳离子基团，模仿接近侧链。用一个或两个位于中心的脱氧尿嘧啶修饰DNA双链体，所述脱氧尿嘧啶在5位被柔性3-氨基丙基或刚性3-氨基丙炔-1-基取代。通过测量5′-和3′-连接染料对之间的时间分辨Förster共振能量转移，获得了端到端螺旋距离和双链体柔性。一种新的分析方法利用了G（t）函数的一阶矩和二阶矩，它只包含能量传递过程。双链体的柔性甚至会因单个正电荷的存在而改变。相反，在双螺旋中引入两个相邻的束缚阳离子会显著改变平均5′-3′距离，但单个阳离子不会：两个相邻的氨基丙基会减少5′-3′距离，而相邻的氨基丙炔基会延长螺旋。
Local DNA deformation arises from an interplay among sequence-related base stacking, intrastrand phosphate repulsion, and counterion and water distribution, which is further complicated by the approach and binding of a protein. The role of electrostatics in this complex chemistry was investigated using tethered cationic groups that mimic proximate side chains. A DNA duplex was modified with one or two centrally located deoxyuracils substituted at the 5-position with either a flexible 3-aminopropyl group or a rigid 3-aminopropyn-1-yl group. End-to-end helical distances and duplex flexibility were obtained from measurements of the time-resolved Förster resonance energy transfer between 5′- and 3′-linked dye pairs. A novel analysis utilized the first and second moments of the G(t) function, which encompasses only the energy transfer process. Duplex flexibility is altered by the presence of even a single positive charge. In contrast, the mean 5′–3′ distance is significantly altered by the introduction of two adjacently tethered cations into the double helix but not by a single cation: two adjacent aminopropyl groups decrease the 5′–3′ distance while neighboring aminopropynyl groups lengthen the helix.
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影响因子：
14.9
作者：
Hardwidge, PR;Zimmerman, JM;Maher, LJ
通讯作者：
Maher, LJ
影响因子：
2.9
作者：
Gold, B
通讯作者：
Gold, B
影响因子：
64.8
作者：
GARTENBERG, MR;CROTHERS, DM
通讯作者：
CROTHERS, DM
影响因子：
2.9
作者：
Booth, J;Brown, T;Lane, AN
通讯作者：
Lane, AN
影响因子：
6.8
作者：
AKAIKE, H
通讯作者：
AKAIKE, H