Genetic and biophysical analysis of morphogen gradient formation

形态素梯度形成的遗传和生物物理分析

基本信息

批准号：
10723239
负责人：
Gavin S Schlissel
金额：
$ 12.5万
依托单位：
WHITEHEAD INSTITUTE FOR BIOMEDICAL RES
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-09-01 至 2025-08-31
项目状态：
未结题

项目摘要

Principal Investigator: Schlissel, Gavin Project summary Animal development and physiology require regular communication among cell types embedded in tissues. Cellular communication commonly relies on signaling proteins, which can transit the space between cells and relay information across a wide range of spatial scales from nanometers to meters. Proper control of signaling range is strictly necessary during animal development, and dysregulation of signaling range can result in a spectrum of embryonic lethal conditions or developmental disorders. The patterning gradient formed by a signaling protein reflects the signaling protein’s ability to travel through the extracellular matrix, which is an amalgam of protein, sugar and lipids that organize cells in natural tissues. Although signaling proteins are thought to diffuse from their source to their target, many proteins violate the assumptions of free diffusion and instead show context-dependent differences in their signaling range. For example, Sonic Hedgehog family developmental morphogens form signaling gradients over ~10µm in the testes, ~50µm in the developing neural tube or in adult hair follicles, and ~300µm in developing long bones. Notably, tissues in which Sonic Hedgehog forms longer signaling gradients tend to express Scube family extracellular matrix proteins, and Scube family proteins can dramatically extend Sonic Hedgehog signaling gradients in cell culture. I suspect that tissue-specific differences in signaling range might reflect direct regulation of Sonic Hedgehog’s diffusion rate, and that regulated diffusion of Hedgehog might reflect a broadly used strategy to control the size of signaling gradients in animals. To understand how morphogens and the extracellular matrix interact to generate appropriately sized signaling gradients, I will measure variation in protein diffusion both between diverse signaling proteins, and between distinct extracellular environments. I will apply this mechanistic understanding to discover how biochemical features of signaling proteins and the extracellular matrix result in size variation among signaling gradients as well as morphological variation among the anatomical features that they pattern. To that end, I propose the following specific aims: 1) Understand how Scube family proteins modify hedgehog diffusion by tracking single particles of sonic hedgehog diffusing through the extracellular matrix. 2) Discover which biochemical features of a signaling protein affect its diffusion rate through the extracellular matrix by developing synthetic morphogens, in which diffusion can be uncoupled from downstream signal transduction. 3) Identify extracellular matrix modifiers of protein diffusion that contribute to tissue- or organism-specific signaling gradient size discrepancies by genetically simulating tissue-specific extracellular matrix variation K99/R00 Fellowship Application October 2022

首席研究员：Schlissel，Gavin 项目概要动物发育和生理学需要组织中嵌入的细胞类型之间的定期通信。细胞通讯通常依赖于信号蛋白，信号蛋白可以在细胞和细胞之间传递空间在从纳米到米的广泛空间尺度上传递信息正确控制信号传输。信号范围在动物发育过程中是严格必要的，信号范围的失调可能会导致一系列胚胎致死状况或发育障碍。信号蛋白形成的图案梯度反映了信号蛋白的移动能力通过细胞外基质，细胞外基质是蛋白质、糖和脂质的混合物，以自然方式组织细胞尽管信号蛋白被认为是从其来源扩散到其目标，但许多蛋白质违反了规定。自由扩散的假设，而是在其信号范围中显示出上下文相关的差异。例如，Sonic Hedgehog 家族发育成形素在测试中形成超过 ~10μm 的信号梯度，发育中的神经管或成人毛囊中约为 50μm，发育中的长骨中约为 300μm。 Sonic Hedgehog 形成较长信号梯度的组织倾向于在细胞外表达 Scube 家族基质蛋白和 Scube 家族蛋白可以显着扩展细胞中的 Sonic Hedgehog 信号梯度文化。我怀疑信号范围的组织特异性差异可能反映了声波的直接调节 Hedgehog 的扩散率以及 Hedgehog 的受调控扩散可能反映了一种广泛使用的策略控制动物信号梯度的大小了解形态发生素和细胞外基质的作用。相互作用以产生适当大小的信号梯度，我将测量蛋白质扩散的变化我将应用这种机制在不同的信号蛋白之间以及不同的细胞外环境之间。了解信号蛋白和细胞外基质的生化特征如何导致信号梯度之间的大小变化以及解剖特征之间的形态变化为此，我提出以下具体目标： 1) 了解 Scube 家族蛋白如何通过跟踪单个声波粒子来改变刺猬扩散刺猬通过细胞外基质扩散。 2) 发现信号蛋白的哪些生化特征影响其通过通过开发合成形态发生素来形成细胞外基质，其中扩散可以与下游信号转导。 3) 识别有助于组织或生物体特异性的蛋白质扩散的细胞外基质修饰剂通过基因模拟组织特异性细胞外基质的信号梯度大小差异变化 K99/R00 奖学金申请 2022 年 10 月