Chromatin higher order dynamics: A single molecule approach

真核生物染色体的高级结构由蛋白质/DNA相互作用控制，蛋白质/DNA相互作用介导DNA折叠成染色质纤维。染色质纤维结构围绕核小体，染色质的基本单位。SNF 2 ATP酶和组蛋白修饰酶重塑核小体，并已被证明在细胞周期和个体发育期间表观遗传密码的产生、维持和改变中发挥关键作用。我们建议研究染色质重塑因子对染色质纤维物理性质的影响。为此，将产生适合于物理化学表征的完全重组模型多核小体阵列。其次，将以制备量纯化确定的原型染色质重塑活性。最后，国家的最先进的单分子磁镊和延时原子力显微镜将被用来严格调查的物理性质和染色质更高的顺序结构转变的动力学催化的染色质重塑。结合多学科的方法，我们希望阐明核小体介导的更高层次的染色质结构转换与无与伦比的分辨率。

Higher order structure of eukaryotic chromosomes is governed by protein/DNA interactions that mediate the folding of DNA into chromatin fibres. Chromatin fibre structure revolves around nucleosomes, the fundamental units of chromatin. SNF2 ATPases and histone modifying enzymes remodel nucleosomes and have been documented to play key roles in the generation, maintenance and alteration of the epigenetic code during the cell cycle and during ontogeny. We propose to study the influence of chromatin remodelling factors on the physical properties of chromatin fibres. To this end, fully recombinant model polynucleosomal arrays suited for physico-chemical characterisation will be generated. Second, defined prototypic chromatin remodelling activities will be purified in preparative quantities. Last, state-of-the-art single molecule magnetic tweezers and time-lapse Atomic Force Microscopy will be employed to rigorously investigate the physical properties and dynamics of chromatin higher order structural transitions catalysed by chromatin remodellers. With this combined multidisciplinary approach we expect to elucidate nucleosome mediated higher order chromatin structural transitions with an unsurpassed degree of resolution.