How do enhancers control the expression of the same transcriptional factor in different regions of the nervous system?

非编码DNA调控元件或增强子控制关键发育调控因子的组织和区域特异性表达，从而在胚胎体的正确形成中发挥关键作用。然而，人们对区域化基因表达是如何通过增强子的作用来实现的知之甚少。拟议的博士项目旨在利用神经系统的发展作为范例来解决这个问题。在胚胎发生过程中，大脑和脊髓来源于不同的祖细胞，这一过程在很大程度上受转录因子Sox2的控制。Sox2在这两个神经系统组成部分的表达是由两种不同的增强子引导的，脊髓中的N1和大脑中的N2。这个博士项目将使用来自人类多能干细胞（hPSCs）的脑和脊髓祖细胞来解剖这两种增强子的功能。利用hPSC分化结合多种技术，包括ChiP-seq和CRISPR/Cas9方法，我们的目标是：1)定义可能区分N1和N2增强子的分子标记；2)检查候选转录因子在这些增强子上的差异结合；3)确定影响其功能的关键序列参数。

Non-coding DNA regulatory elements or enhancers control tissue and region-specific expression of critical developmental regulators thus playing a crucial role in the correct formation of the embryonic body. However, not much is known how regionalized gene expression is achieved through enhancer action. The proposed PhD project aims to address this issue using the development of the nervous system as a paradigm. During embryogenesis, the brain and the spinal cord are derived from different progenitors and this process is controlled to a large extent by the transcription factor Sox2. Sox2 expression into these two components of the nervous system is directed by two distinct enhancers, N1 in the spinal cord and N2 in the brain. This PhD project will employ brain and spinal cord progenitors derived from human pluripotent stem cells (hPSCs) in order to dissect the function of these two enhancers. Using hPSC differentiation in combination with a variety of techniques including ChiP-seq and CRISPR/Cas9 approaches we aim to:1) define the molecular hallmarks that may distinguish the N1 and N2 enhancers2) examine the differential binding of candidate transcription factors on these enhancers3) identify critical sequence parameters influencing their function.