Enhancer activation mechanisms in cranial neural crest osteoblast differentiation

项目摘要 增强子在启动和维持细胞特异性转录程序的表达中起着至关重要的作用。一 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 转录辅助调节子与增强子的结合。与增强子相关的染色质修饰酶 功能在人类颅面疾病中通常发生突变，包括组蛋白甲基化酶，脱甲基酶， 乙酰化酶、染色质阅读器和染色质重塑蛋白。许多染色质修饰因子 生物化学关联并可共调节神经细胞内的增强子和转录激活事件， 前面部骨和软骨来源的干细胞。我们已经模拟了其中的几个 通过组织特异性敲除小鼠神经细胞中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： 成骨细胞分化过程中的原代颅神经嵴细胞的染色质分布。神经嵴细胞 缺乏染色质修饰机制的人将被分子分析以破坏增强染色质 国家，并确定这些因素之间的合作功能。该提案将利用以下组合： 生物化学、遗传学和低细胞数基因组学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中的作用。

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 primary cranial neural crest cells undergoing osteoblast differentiation. 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.