Dissecting the role of Erk signaling dynamics in positioning and coordinating germ layer fates

项目摘要： 越来越清楚的是，细胞将信息解释和编码到多个细胞中的一种方式是 命运是通过动态编码多路复用信息。这对于MAPK/Erk途径尤其如此， 其控制许多细胞过程，包括细胞增殖、分化和迁移。多年来， 不同的结果是由相同的途径控制仍然难以捉摸，但单细胞研究的出现， 光遗传学已经阐明了Erk活性可以解释为不同细胞命运的许多方式， 甚至最近，动态在这些复杂决策中的作用。发展Erk的作用 然而，还没有研究确定和协调人原肠胚形成的动力学。我们将 联合收割机活细胞激酶活性报告基因和细胞内信号传导途径的光遗传学控制， ERK动力学在定位和协调三个胚层中的作用。此外，我们将发现 引起RASopathy的突变是否会影响人类原肠胚形成， 干预 这项建议汇集了干细胞和分子工程的最新进展。我们利用 在2D微图案化、细胞光遗传学控制、活细胞激酶活性报告和CRISPR Cas9方面的进展 基因组编辑这些技术共同为我们提供了前所未有的控制和可视化， 人类原肠胚形成的微工程模型，从而使我们能够研究动态的原则， 信息传输我们的平台不面临限制人类胚胎的相同道德障碍 研究，使我们能够提供有关人类胚胎发育的其他信息。在这 建议我们专注于Erk信号动力学在协调三个胚层中的作用，以及揭示 RASopathy突变的影响。在目标1中，我们将使用Erk激酶对Erk信号动力学进行成像和定量。 在原肠胚形成过程中的易位报告，并确定哪些特征的信号动力学， 预测胚层的命运。目标2将使我们能够确定这些动力学特征中的哪些足以 使用细胞光遗传学确定细胞命运结果。最后，在目标3中，我们将揭示RASopathy 突变导致原肠胚形成缺陷，并研究这些突变是否与Erk动力学的破坏有关。 使用CRISPR Cas9基因编辑和我们的2D gastruloid模型的签名。接近这个细胞生物学 从系统层面的角度来看，使用可重复的精确可控的工具， 如果没有光遗传学和微工程平台，这种技术是不可能实现的，它有可能在这个领域带来新的光明。

Project Summary: It is becoming increasingly clear that one of the ways that cells interpret and encode information into multiple cell fates is by multiplexing information through dynamic encoding. This is especially true for the MAPK/Erk pathway, that governs many cell processes including cell proliferation, differentiation and migration. For years, how such diverse outcomes were controlled by the same pathway remained elusive, but the advent of single cell studies and optogenetics has elucidated the many ways in which Erk activity can be interpreted into distinct cell fates, and even more recently, the role of dynamics in these complex decisions. The role of developmental Erk dynamics in determining and coordinating human gastrulation, however, has not yet been investigated. We will combine live cell kinase activity reporters and optogenetic control over intracellular signaling pathways to probe the role of ERK dynamics in positioning and coordinating the three germ layers. Additionally, we will uncover whether RASopathy causing mutations influence human gastrulation to pace the way for potential therapeutic intervention. This proposal brings together recent advances in stem cell and molecular engineering. We utilize advances in 2D micropatterning, cellular optogenetic control, live cell kinase activity reporters and CRISPR Cas9 genome editing. Together, these technologies give us unprecedented control over and visualization of microengineered models of human gastrulation, thereby enabling us to investigate the principles of dynamic information transmission. Our platform does not face the same ethical barriers that have limited human embryo research, allowing us to provide otherwise unavailable information about human embryonic development. In this proposal we focus on the role of Erk signaling dynamics in coordinating the three germ layers, as well as uncover impact of RASopathy mutations. In Aim 1 we will image and quantify Erk signaling dynamics using the Erk kinase translocation reporter during the process of gastrulation and determine which features of signaling dynamics are predictive of germ layer fate. Aim 2 will allow us to identify which of these dynamical features are sufficient to determine the cell fate outcome using cellular optogenetics. Finally, in Aim 3 we will uncover whether RASopathy mutations lead to gastrulation defects and investigate whether these are linked to disruption to Erk dynamical signatures using CRISPR Cas9 gene editing and our 2D gastruloid model. Approaching this cell biological question from a systems level perspective, using reproducible precisely controllable tools that are otherwise unavailable without optogenetics and microengineered platforms, has the potential to shine new light on the field.