Mechanisms of apical expansion in calvarial bone morphogenesis

颅骨骨形态发生中根尖扩张的机制

• 批准号: 10212367
• 负责人: RADHIKA P ATIT
• 金额: $ 17.29万
• 依托单位: CASE WESTERN RESERVE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-07-07 至 2024-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10212367
• 关键词: 3-Dimensional; Actins; Address; Apical; Behavior; Biophysics; Bone Growth; Brain; Calvaria; Cell Polarity; Cells; Cephalic; Chemotaxis; Congenital Abnormality; Craniofacial Abnormalities; Craniosynostosis; Cues; Data; Defect; Development; Devices; Dysplasia; Embryo; Etiology; Event; Extracellular Matrix; Eye; Fibronectins; Goals; Human; Image; In Vitro; Ligands; Light; Liquid substance; Live Birth; Magnetism; Maps; Mesenchymal; Mesenchyme; Morphogenesis; Movement; Mus; Mutant Strains Mice; Natural regeneration; Organ; Organogenesis; Outcome; Pathway interactions; Pattern; Process; Property; Proteins; Role; Sensory; Signal Pathway; Signal Transduction; Syndrome; Testing; Therapeutic; Tissues; To specify; Variant; WNT Signaling Pathway; base; biophysical techniques; bone; cell behavior; cell motility; cranium; experimental study; in vivo; insight; intercalation; intramembranous bone; live cell imaging; migration; mineralization; mouse genetics; mutant; new therapeutic target; novel; organ growth; planar cell polarity; progenitor; protein expression; skeletal dysplasia; suture fusion

Congenital skull defects such as craniosynostosis and dysplasias occur in 1/2500 live births with detrimental consequences for brain and sensory organ development. We lack basic understanding of how and why the skull bones grow towards the apex, which impacts the direction of intramembranous mineralization and fusion of sutures. The signaling factors and cellular mechanisms underlying the apical expansion of skull bone progenitors remain unidentified. We recently found mouse skull bone progenitors migrate from the supraorbital arch region to the apex and this movement is disrupted in conditional mesenchyme Wntless mutants, that lack all ligand secretion. We also identified a graded expression of fibronectin extracellular matrix in the cranial mesenchyme that is dependent on mesenchyme Wnts, suggesting cell movement by a process of durotaxis in which cells migrate along a stiffness gradient of fibronectin. This proposal intends to define, in vivo, the role of the cranial mesenchyme non-canonical Wnts in directing cellular polarity and durotaxis. In this multi-PI proposal, we will leverage our integrative expertise in conditional mouse genetics, live cell imaging, and emerging biophysical approaches in vivo to address our central hypothesis that mesenchyme Wnts-dependent fibronectin orients the collective movement of calvarial bone progenitors toward the apex by durotaxis. Towards the hypothesis, in Aim1 we will identify the role of mesenchyme Wnts signaling in regulating cell movement behaviors with live light-sheet imaging. In Aim2, we will test if fibronectin directs a tissue-stiffness gradient and collective movement of SOM cells apically by durotaxis. Key deliverables of this R21 proposal include: 1. Developing a framework of cellular behaviors during calvarial bone morphogenesis, 2. the role of SOM-Wnt as a global spatial cue, and 3. the role of durotaxis driven cell movements on a graded fibronectin matrix during calvarial bone growth. Impact: Currently, we lack a conceptual framework for understanding cell movement in calvarial bone expansion, despite its role in highly prevalent craniosynostosis and cranial skeletal dysplasias. The results from these proof-of-concept experiments will serve as a new paradigm in our understanding of cell movement in 3D in mesenchymal cells and provide us fresh insights into skull bone morphogenesis and congenital defects.

1/2500 活体中出现颅缝早闭和发育不良等先天性颅骨缺陷 对大脑和感觉器官发育产生不利影响的出生。我们缺乏基本的 了解颅骨如何以及为何向顶点生长，这会影响方向 膜内矿化和缝线融合。信号传导因子和细胞 颅骨骨祖细胞顶端扩张的机制仍不清楚。 我们最近发现小鼠头骨骨祖细胞从眶上弓区域迁移 到顶点，并且这种运动在条件间充质 Wntless 突变体中被破坏， 缺乏所有配体分泌。我们还确定了纤连蛋白细胞外基质的分级表达 存在于依赖于间充质 Wnts 的颅内间充质中，表明细胞运动 通过杜罗轴过程，其中细胞沿着纤连蛋白的硬度梯度迁移。这 该提案旨在体内定义颅间充质非典型 Wnt 在体内的作用 指导细胞极性和杜罗轴。在这个多 PI 提案中，我们将利用我们的综合能力 条件小鼠遗传学、活细胞成像和新兴生物物理方法方面的专业知识 体内解决我们的中心假设，即间充质 Wnts 依赖性纤连蛋白 通过以下方式将颅骨骨祖细胞的集体运动定向到顶点 杜罗轴。针对该假设，在 Aim1 中，我们将确定间充质 Wnts 的作用 通过实时光片成像调节细胞运动行为的信号传导。在Aim2中，我们将测试 如果纤连蛋白通过以下方式指导组织硬度梯度和 SOM 细胞的集体运动： 杜罗轴。 R21 提案的主要成果包括： 1. 开发蜂窝网络框架 颅骨骨形态发生过程中的行为，2. SOM-Wnt 作为全局空间线索的作用， 3.颅骨期间杜罗轴驱动细胞运动在分级纤连蛋白基质上的作用 骨骼生长。 影响：目前，我们缺乏理解颅盖细胞运动的概念框架 骨扩张，尽管它在高度普遍的颅缝早闭和颅骨骨骼发育中发挥着作用 发育不良。这些概念验证实验的结果将成为一个新的范例 帮助我们理解间充质细胞的 3D 细胞运动，并为我们提供新的见解 颅骨骨形态发生和先天性缺陷。

项目成果

Apical expansion of calvarial osteoblasts and suture patency is dependent on graded fibronectin cues.

颅骨成骨细胞的顶端扩张和缝线通畅取决于分级的纤连蛋白线索。

• DOI: 10.1101/2023.01.16.524278
• 发表时间: 2023
• 期刊: bioRxiv : the preprint server for biology
• 作者: Feng,Xiaotian;Molteni,Helen;Gregory,Megan;Lanza,Jennifer;Polsani,Nikaya;Wyetzner,Rachel;Hawkins,MBrent;Holmes,Greg;Hopyan,Sevan;Harris,MatthewP;Atit,RadhikaP
• 通讯作者: Atit,RadhikaP