The emergence of complex structural organisation in skeletal muscle

骨骼肌中复杂结构组织的出现

基本信息

批准号：
BB/W006944/1
负责人：
Tim Saunders
金额：
$ 93.19万
依托单位：
University of Warwick
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2022
资助国家：
英国
起止时间：
2022 至无数据
项目状态：
未结题

来源：
https://gtr.ukri.org/projects?ref=BB%2FW006944%2F1
关键词：
emergence complex structural organisation skeletal

项目摘要

During development, an organism goes from a single fertilised cell through to an adult with multiple organs. These organs are precisely shaped and the internal cellular structure tightly defined to ensure efficient function. For example, the lungs generate a large-scale branching network to enable rapid oxygen transport into the bloodstream. In the skeletal muscle, muscle cells form elongated, and typically multinucleated, fibres that enable the generation of significant force. How complex organ shape emerges during development has been a long standing question in biology, going back to before even D'Arcy Thompson. Yet, understanding the underlying processes has long proven challenging, partially due to the difficulty of imaging the cellular processes at appropriate spatial and temporal resolution. Recent years have seen three major advances that are helping us to tackle this challenge. First, biophysical models have proven to be very powerful in describing the structural changes in the material properties of biological materials. Developing tissues can undergo transitions, such as between fluid-like (i.e. rapid cell rearrangements) and solid-like (i.e. rigid internal structure). Second, imaging advances mean we can record with subcellular resolution the dynamics of cell morphogenesis in living embryos. Third, there have been major steps forward in our ability to segment and quantify complex biological imaging data using machine learning and more traditional approaches. Analysis of muscle fibre formation is especially challenging due to the speed with which the cell structure changes, including cell fusion. By combining these advances with the powerful genetics and optical accessibility of the zebrafish embryo, here we aim to dissect how the internal structural organisation of skeletal muscle emerges. Through the following Aims, we explore if the developing skeletal muscle undergoes a material change in its properties and how cellular processes drive cell and tissue shaping:1) Provide the first dissection of the dynamics for every cell within an internal vertebrate organ as they reach their final position and morphology. 2) Uncover the mechanisms happening within the cells that drive cell and nucleus reshaping and positioning.3) Use suitable mutants to perturb the cellular environment to test our models of cell and tissue shaping.In Aim 1, we will develop imaging and image analysis techniques to allow us to access the cellular behaviour throughout initial skeletal muscle development. We will track the position and morphology of every cell within each selected future muscle segment as they go from round cells through to the highly elongated and tightly structured muscle. The quantitative data is a key input into our analysis of the tissue structural order, to test if there are hallmarks of transitions in the material properties.In Aim 2, we dissect some of the subcellular mechanisms driving the changes in cell and tissue shape. We focus on microtubules due to their importance in a range of cellular processes associated with muscle formation. We will utilise lattice light-sheet microscopy - which enables very fast imaging at high spatial resolution - to record the dynamics of microtubules and their associated motor proteins during skeletal muscle formation. We will combine this with suitable drug and light-tuneable perturbations to dissect the role of microtubules in guiding muscle morphogenesis.In Aim 3, we utilise a range of mutants to further explore the mechanisms driving tissue organisation. We focus on perturbing muscle cell fate specification and inhibiting muscle fusion. These perturbations allow us to access the role of both biochemical and biomechanical inputs in driving skeletal muscle formation.Around 40% of human body mass is skeletal muscle. Using zebrafish development. we will dissect the fundamental mechanisms ensuring this tissue is precisely structured.

在发育过程中，有机体从单个受精细胞到具有多个器官的成年人。这些器官精确地形状，内部细胞结构紧密定义以确保有效的功能。例如，肺部产生一个大规模的分支网络，以使氧气快速转运到血液中。在骨骼肌中，肌肉细胞形成细长，通常是多核的纤维，可以产生重要的力。在开发过程中，复杂的器官形状如何在生物学上是一个长期存在的问题，甚至可以追溯到D'Arcy Thompson。但是，理解基本过程长期以来一直在证明具有挑战性，部分原因是在适当的空间和时间分辨率下成像细胞过程的困难。近年来，有三个重大进步有助于我们应对这一挑战。首先，事实证明，生物物理模型在描述生物材料的材料特性的结构变化方面非常有力。发育的组织可以发生过渡，例如流体样（即快速细胞重排）和固体样（即刚性内部结构）之间的过渡。其次，成像进步意味着我们可以通过亚细胞分辨率记录活细胞形态发生的动力学。第三，我们可以使用机器学习和更传统的方法来细分和量化复杂的生物成像数据的能力进行了重大步骤。由于细胞结构变化（包括细胞融合）的速度，肌肉纤维形成的分析尤其具有挑战性。通过将这些进步与斑马鱼胚胎的强大遗传学和光学可及性相结合，我们旨在剖析骨骼肌的内部结构组织如何出现。通过以下目标，我们探讨了发育中的骨骼肌是否经历了其特性的物质变化以及细胞过程如何驱动细胞和组织形状：1）为每个细胞在脊椎动物内器官内的每个细胞中提供了第一次解剖，因为它们达到了最终的位置和形态。 2）揭示细胞内发生的机制，这些机制驱动细胞和核重塑和定位。3）使用合适的突变体扰动细胞环境来测试我们的细胞和组织形状模型。在AIM 1中，我们将开发成像和图像分析技术，使我们能够在初始骨骼肌肌肉发育中访问细胞行为。我们将跟踪每个选定的未来肌肉段中每个细胞的位置和形态，它们从圆形细胞到高度伸长且结构紧密的肌肉。定量数据是我们对组织结构顺序分析的关键输入，以测试材料特性中是否存在过渡的标志。由于微管在与肌肉形成相关的一系列细胞过程中的重要性，我们专注于微管。我们将利用晶格灯页显微镜（可以在高空间分辨率下进行非常快速的成像）记录骨骼肌形成过程中微管及其相关运动蛋白的动力学。我们将将其与合适的药物和可轻调的扰动结合起来，以剖析微管在引导肌肉形态发生中的作用。在AIM 3中，我们利用一系列突变体来进一步探索驱动组织组织的机制。我们专注于扰动肌肉细胞命运规格和抑制肌肉融合。这些扰动使我们能够访问生化和生物力学输入在驱动骨骼肌形成中的作用。40％的人体体重是骨骼肌。使用斑马鱼的发展。我们将剖析确保该组织精确结构的基本机制。

项目成果

期刊论文数量（3）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Slow muscles guide fast myocyte fusion to ensure robust myotome formation despite the high spatiotemporal stochasticity of fusion events.

DOI：
10.1016/j.devcel.2022.08.002
发表时间：
2022-08
期刊：
Developmental cell
影响因子：
11.8
作者：
Mario A. Mendieta-Serrano;Sunandan Dhar;Boon Heng Ng;R. Narayanan;Jorge J.Y. Lee;H. T. Ong;P. Toh;A. Röllin;Sudipto Roy;T. Saunders
通讯作者：
Mario A. Mendieta-Serrano;Sunandan Dhar;Boon Heng Ng;R. Narayanan;Jorge J.Y. Lee;H. T. Ong;P. Toh;A. Röllin;Sudipto Roy;T. Saunders

Optogenetic control of YAP can enhance the rate of wound healing

YAP的光遗传学控制可以提高伤口愈合率