Abstract:
Under different conditions, the DNA double helix can take different geometric forms. Of the large number of its conformations, in addition to the \"canonical\" B form, the A, C, and Z forms are widely known, and the D, Hoogsteen, and X forms are less known. DNA locally takes the A, C, and Z forms in the cell, in complexes with proteins. We compare different methods for detecting non-canonical DNA conformations: X-ray, IR, and Raman spectroscopy, linear and circular dichroism in both the infrared and ultraviolet regions, as well as NMR (measurement of chemical shifts and their anisotropy, scalar and residual dipolar couplings and inter-proton distances from NOESY (nuclear Overhauser effect spectroscopy) data). We discuss the difficulties in applying these methods, the problems of theoretical interpretation of the experimental results, and the prospects for reliable identification of non-canonical DNA conformations.
摘要:
在不同的条件下,DNA双螺旋可以采取不同的几何形式。在它的大量构象中,除了“规范”B表格之外,A,C,Z形式是众所周知的,还有D,Hoogsteen,和X形式是鲜为人知的。DNA在当地取A,C,Z在细胞中形成,与蛋白质的复合物。我们比较了检测非规范DNA构象的不同方法:X射线,IR,和拉曼光谱,红外和紫外区域的线性和圆二色性,以及NMR(化学位移及其各向异性的测量,标量和残余偶极耦合以及来自NOESY(核Overhauser效应光谱)数据的质子间距离)。我们讨论了应用这些方法的困难,实验结果的理论解释问题,以及可靠鉴定非规范DNA构象的前景。