INVESTIGATING NOVEL DNA FLUORSCENCE LABELING PROBES

这个子项目是利用由NIH/NCRR资助的中心拨款提供的资源的许多研究子项目之一。子项目和调查员(PI)可能从另一个NIH来源获得了主要资金，因此可能会出现在其他CRISE条目中。列出的机构是针对中心的，而不一定是针对调查员的机构。Burgess和他的同事已经开发了几种不同类型的用于DNA标记的荧光探针，其中包含不止一个荧光发色团，这些荧光发色团具有明显的可见荧光光谱，但在同一波长下具有相同的高吸收截面。两种类型的此类分子包括试验系统，该系统包括具有连接到碱基上的强荧光基团的寡核苷酸，例如胸苷，以及结合到DNA中的刚性的、共轭的、荧光的胸苷三磷酸盐。本项目的目的是通过两种不同的方法直接测量能量传递动力学：荧光上转换(分辨率150fs)和双光子诱导荧光技术(分辨率~100ps)。最近与其他涉及罗丹明和荧光素衍生物的双生色团探针的比较表明，能量转移速率与这两个生色团的电子跃迁矩的相对取向和连接它们的不饱和基团的轴有关。目前正在通过对每种类型生色团对的能量转移速率和荧光各向异性的研究来检验这些相关性。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. K. Burgess and co-workers have developed several different types of fluorescence probes for DNA labeling containing more than one fluorescent chromophore, which have distinct visible fluorescence spectra and yet have the same high absorption cross sections at a common wavelength. Two types of such molecules have included trial systems involving oligonucleotides with strongly fluorescent groups conjugated to a nucleobase such as thymidine, and rigid, conjugated, fluoresceinated thymidine triphosphates incorporated into DNA. The aim of the current project is to directly measure energy transfer dynamics by two distinct methods: fluorescence upconversion (150 fs resolution) and a two-photon induced fluorescence technique (~100 fs resolution). Recent comparisons with other dual chromophore probes, involving derivatives of rhodamine and fluorescein, have revealed a correlation of the energy transfer rate with the relative orientation of the electronic transition moments of the two chromophores and the axis of the unsaturated group connecting them. These correlations are currently being examined, through studies of both the energy transfer rate and the fluorescence anisotropy of each type of chromophore pair.