Revealing DNA's Secret Structures with Ruthenium: From the Test Tube, to the Cell

DNA不仅仅是沃森-克里克双螺旋结构。作为一种柔性聚合物，它采用许多不同的二级结构以不同的方式折叠。(i)对这些结构所知甚少- -它们如何和何时形成，它们起什么作用以及它们的结构与它们的作用有何关系。即便如此，这种“另类”结构与基因的开启/关闭有关，从而与糖尿病和癌症等遗传疾病有关。这个为期3.5年的博士奖学金由EPSRC博士培训合作伙伴关系资助，重点研究一个这样的结构，即i-Motif （iM）。2018年已证实生物体内存在iM，但对其生物结构/功能关系知之甚少，并且由于缺乏可应用于活细胞和生物的有效检测方法，研究受到阻碍。然而，我们最近发现了一种钌复合物，它可以在体外通过磷光寿命增加来检测存在其他DNA形式的iM，（iii）并且可能与生命系统兼容。这个学生的目标是改进我们的先导化合物，增加其反应的强度和特异性，提高我们对其磷光开关的理解，并开始将这项研究从试管转化为细胞的工作。因此，这个由约翰·菲尔登博士领导的项目是高度跨学科的。它将涉及广泛的技术培训，从新的配体和复合物的合成，到它们与DNA相互作用的特征及其在细胞中的作用，并涉及内部和外部合作。

iThere is a lot more to DNA than the Watson-Crick double helix. As a flexible polymer, it folds in different ways adopting many different secondary structures.(i) Much less is known about these structures - how and when they form, what they do and how their structure relates to their role. Even so, such "alternative" structures have been linked to switch on/off of genes, and thus genetic diseases such as diabetes and cancer.This 3.5 year PhD studentship is funded by an EPSRC Doctoral Training Partnership and focuses on one such structure, the i-Motif (iM). Existence of iM in organisms was proven in 2018,(ii) but little is known about its biological structure/function relationships, and research is held back by a lack of effective detection methods that can be applied to live cells and organisms. However, we recently discovered a ruthenium complex that can, in vitro, detect iM in the presence of other DNA forms through a phosphorescence lifetime increase,(iii) and is likely compatible with living systems. The goal of this studentship is to improve our lead compound, increasing the strength and specificity of its response, improve our understanding of its phosphorescence switch on, and begin the work of translating this research from the test tube to cells. As such, the project, led by Dr John Fielden, is highly interdisciplinary. It will involve training in a wide range of techniques, from synthesis of new ligands and complexes, to characterisation of their interaction with DNA and their effect in cells, and involves both internal and external collaborations.