Cranial placode induction from human embryonic stem cells

描述（由申请人提供）：颅基板是短暂的胚胎结构，最终发育成感觉器官和垂体前叶（一个主要的内分泌腺）的一部分。这些基板起源于外胚层，是三种胚层之一，已知外胚层可产生表皮、脑和脊髓。基板发育在发育中的脑和表皮两侧的一个小区域。目前，我们对这些短暂结构是如何在人体中形成的了解甚少。为了更好地了解这一过程，该项目旨在确定将外胚层限制为非神经命运并允许其发育成不同基板的潜在分子机制。由于这些组织出现的时间点较早，因此将使用人类胚胎干细胞来模拟其发育。干细胞将经过不同的培养条件，以确定首先获得非神经外胚层的最佳条件，其次是胎盘前外胚层，最后是不同的基板。所有这些组织都由一组独特的基因定义，这些基因将在单细胞分辨率下分析共表达。这些知识可用于研究基因缺陷如何改变基因位发育。为了实现这一目标，我们将设计一种EYA1基因敲除的人类胚胎干细胞系，并在单细胞分辨率下检测这些细胞在基板发育过程中的转录谱变化。我们从这项研究中学到的东西对影响感觉器官系统（包括内耳）的人类疾病的研究具有广泛的意义。

DESCRIPTION (provided by applicant): The cranial placodes are transient embryonic structures that eventually develop into portions of the sense organs and the anterior pituitary, a major endocrine gland. These placodes arise from the ectoderm, one of the three germ layers, which is known to give rise to the epidermis, brain, and spinal cord. The placodes develop in a small region that is flanked by the developing brain and epidermis. Currently we understand very little of how these transient structures develop in humans. To gain better insight into this process, this project aims to determine the underlying molecular mechanisms that restrict the ectoderm to a non-neural fate and allow it to develop into the different placodes. Due to the early time points in which these tissues arise, development will be modeled using human embryonic stem cells. Stem cells will be subjected to different culture conditions to determine the optimal conditions to derive first non-neural ectoderm, followed by pre-placodal ectoderm and finally the different placodes. All of these tissues are defined by a distinct set of genes, which will be analyzed for co-expression at single cell resolution. This knowledge can be used to study how defects in genes alter placode development. As a step towards this, we will engineer an EYA1 knockout human embryonic stem cell line and assay changes in the transcriptional profile of these cells during placode development at single cell resolution. What we learn from this research has broad implications for study of human disease affecting the sensory organ systems, including the inner ear.