Enhancer activation roles and mechanisms in craniofacial development

项目概要 增强子在启动和维持细胞特异性转录程序的表达中发挥着至关重要的作用。一个 增强子激活和基因调控的关键特征是改变局部染色质状态以促进结合 转录共调节子到增强子。与增强子相关的染色质修饰酶 人类颅面疾病中的功能通常发生突变，包括组蛋白甲基化酶、去甲基化酶、 乙酰酶、染色质读取器和染色质重塑蛋白。许多染色质修饰因子 生物化学上关联并可能共同调节神经内的增强子和转录激活事件 嵴，干细胞，源自前面部骨和软骨。我们已经对其中的几个进行了建模 通过组织特异性敲除小鼠神经染色质修饰因子来治疗人类颅面疾病 嵴细胞。本提案中概述的实验将通过以下方式表征从头增强子激活： 分化原代神经嵴细胞的染色质分析。神经嵴细胞缺乏染色质 将对修饰机制进行分子分析，以破坏增强子染色质状态并识别 这些因素之间的协同作用。该提案将结合生物化学、遗传、 和低细胞数基因组方法来阐明基于染色质的增强子激活在 颅面疾病发病机制。

Project Summary Enhancers play a vital role in initiating and maintaining expression of cell specific transcriptional programs. A key feature in enhancer activation and gene regulation is changing the local chromatin state to facilitate binding of transcriptional co-regulators to enhancers. Chromatin-modifying enzymes that are associated with enhancer function are commonly mutated in human craniofacial disorders including histone methylases, demethylases, acetylases, chromatin readers, and chromatin remodeling proteins. Many of these chromatin-modifying factors biochemically associate and may co-regulate enhancer and transcriptional activation events within neural crest, stem cells from which anterior facial bone and cartilage are derived. We have modeled several of these human craniofacial disorders through tissue specific knockout of chromatin-modifying factors in mouse neural crest cells. The experiments outlined in this proposal will characterize de novo enhancer activation by chromatin profiling of differentiating primary neural crest cells. Neural crest cells deficient in chromatin- modifying machinery will be analyzed molecularly for disruption of enhancer chromatin states and to identify cooperative functions between these factors. This proposal will utilize a combination of biochemical, genetic, and low cell number genomic approaches to elucidate the role of chromatin-based enhancer activation in craniofacial disorder pathogenesis.