单个TATA盒结合蛋白对DNA的逐步弯曲
Stepwise bending of DNA by a single TATA-box Binding Protein
摘要：
TATA盒结合蛋白（TBP）是所有三种真核RNA聚合酶所必需的，用于启动大多数启动子的转录。TBP识别、结合并弯曲DNA中称为"TATA盒“的启动子序列。我们目前的研究结果，个别酿酒酵母TBPs与含有TATA盒的单个DNA分子相互作用。使用视频显微镜，我们观察到的布朗运动的珠子栓由短的表面结合的DNA。当TBP结合并弯曲DNA时，DNA的构象发生变化，与未弯曲的DNA相比，拴系珠的布朗运动的幅度降低。我们检测到个人的结合和解离事件，并推导出动力学参数的过程。通过增加盐浓度或通过使用光镊直接拉动拴系的珠来诱导解离。除了明确定义的自由和束缚类的布朗运动，我们观察到另外两类运动。这些额外的类被确定为具有三步线性结合途径上的中间状态。讨论了中间态的生物学意义。
英文摘要：
The TATA-box Binding Protein (TBP) is required by all three eukaryotic RNA polymerases for the initiation of transcription from most promoters. TBP recognizes, binds to, and bends promoter sequences called ``TATA-boxes'' in the DNA. We present results from the study of individual Saccharomyces cerevisia TBPs interacting with single DNA molecules containing a TATA-box. Using video microscopy, we observed the Brownian motion of beads tethered by short surface-bound DNA. When TBP binds to and bends the DNA, the conformation of the DNA changes and the amplitude of Brownian motion of the tethered bead is reduced compared to that of unbent DNA. We detected individual binding and dissociation events and derived kinetic parameters for the process. Dissociation was induced by increasing the salt concentration or by directly pulling on the tethered bead using optical tweezers. In addition to the well-defined free and bound classes of Brownian motion, we observed another two classes of motion. These extra classes were identified with intermediate states on a three-step, linear binding pathway. Biological implications of the intermediate states are discussed.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
