METAL IONS AND INFORMATION TRANSFER--MECHANISM OF RNA SYNTHESIS

金属离子对核酸结构和功能的影响 功能已经确定。 现在的主要焦点是 在活性位点的RNA合成机制 RNA聚合酶。 的相互作用的几何 酶的活性位点在 转录过程来确定这种几何结构 在转录过程中发生变化并影响其操作。 一个全面的机制，以确保忠实于 复制遗传密码的技术已经发展起来， 通过聚合酶检测互补性， 在DNA碱基和传入的碱基之间 核苷三磷酸 聚合酶将其 构象，以防止键形成时，基板 不是互补的，而酶在其他方面仍然存在， 在适当的构象中形成键， 用正确的碱进行有效聚合。 的 结构模型被用来理解 DNA损伤、启动子和转录的影响 转录因子。

The effects of metal ions on nucleic acids structure and function have been determined. The primary focus is now on the mechanism of RNA synthesis at the active site of RNA polymerase. The geometry of interaction at the active site of the enzyme is being probed during the transcription process to determine how this geometry changes during transcription and affects its operation. A comprehensive mechanism for assuring fidelity in copying the genetic code has been developed which depends on the sensing by the polymerase of the complementarity between the DNA base and the base of the incoming nucleoside triphosphate. The polymerase shifts its conformation to prevent bond formation when the substrate is not complementary, while the enzyme otherwise remains in the proper conformation for bond formation to allow efficient polymerization with the correct base. The structural model is being applied to understand the effect of DNA damage, promoters, and transcription factors on transcription.