Probing Bone Morphogenetic Protein function in Cranial Neural Crest cells.

探讨颅神经嵴细胞中的骨形态发生蛋白功能 口面部区域最为复杂。它有各种各样的形状，并且是一些高度专业化的结构的所在地。其发育的核心是颅神经嵴细胞（CNC）。在胚胎发育过程中，CNC 细胞从神经板边缘迁移到鳃弓，从而形成面部突出和不同的组织。 CNC 细胞是多能干细胞，可产生骨骼、软骨、神经、牙齿、神经胶质细胞、黑素细胞和面部结缔组织。尽管只有少数细胞外信号网络，例如音刺猬 (Shh)、骨形态发生蛋白 (Bmp)、成纤维细胞生长因子 (Fgf) 和 Wnt/β-连环蛋白信号传导，其重要性已得到充分证实，但控制其迁移、分化和增殖的信号仍只得到部分了解。这些途径在发育过程中以反复的方式使用，因此其信号活动的地点、时间和持续时间都很重要。  在我的小组中，我们试图了解 Bmp 信号如何促进口面部结构的发育。我们使用 Bmp 小鼠突变体的功能基因组学来表征 Bmp 体内调节的细胞和分子过程。在该项目中，将探讨 Bmp 信号在 CNC 细胞迁移和分化中的作用。 Bmp7 在 CNC 细胞中表达，Bmp7 缺陷会影响 CNC 衍生物，例如雪旺细胞、黑素细胞和三叉神经节。根据已发表的初步数据，我们假设 Bmp7 对于细胞骨架组织、细胞极化和树突形成至关重要。 Bmp7 缺陷将因此影响细胞分层、定向迁移和细胞分化。使用转基因工具可视化 Bmp 信号、Bmp 表达或标记克隆 CNC 细胞，并结合微型计算机断层扫描 (μCT)、光学投影断层扫描 (OPT) 和共焦显微镜，我们将在 3D 中可视化与 Bmp7 相关和依赖的 CNC 细胞迁移、增殖和分化。 功能胚胎学和基因/蛋白质表达研究将确定 Bmp7 功能至关重要的阶段。  细胞测定将允许测试 Bmp7 对 CNC 外植体培养物的直接影响。我们的目标是定义依赖于 Bmp7 的分子和细胞过程，并确定许多看似相当不同的细胞结果是否是细胞骨架组织发生根本变化的结果。 该项目为研究生和本科生提供了令人兴奋的机会，让他们接受尖端成像和先进转基因技术、胚胎学、组织学和基因表达分析（包括下一代测序）方面的培训，并从国内和国际合作中受益。

Probing Bone Morphogenetic Protein function in Cranial Neural Crest cells The orofacial region is most complex. It comes in a wide variety of shapes and is home to several highly specialized structures. Central to its development are cranial neural crest cells (CNC). During embryonic development CNC cells migrate from the neural plate border to the branchial arches from which the facial prominences and different tissues are formed. CNC cells are multipotent stem cells that give rise to bone, cartilage, nerves, teeth, glial cells, melanocytes, and connective tissue of the face. The signals controlling their migration, differentiation, and proliferation are still only partly understood, though the importance of only a handful of extracellular signalling networks, such as Sonic hedgehog (Shh), Bone Morphogenetic Protein (Bmp), Fibroblast Growth Factor (Fgf), and Wnt/ß-catenin signalling, is well established. These pathways are used in a reiterated fashion during development, and thus place, time, and duration of their signalling activity are all important.  In my group, we try to understand how Bmp signalling contributes to the development of orofacial structures. We use functional genomics on Bmp mouse mutants to characterise cellular and molecular processes regulated by Bmp in vivo. In this project the roles of Bmp signaling in migration and differentiation of CNC cells will be addressed. Bmp7 is expressed in CNC cells and Bmp7-deficiency affects CNC-derivatives such as Schwann cells, melanocytes, and the trigeminal ganglion. From published and preliminary data, we hypothesize that Bmp7 is critical for cytoskeletal organization, cell polarization, and dendrite formation. Bmp7-deficiency will in consequence affect cell delamination, directed migration, and cell differentiation. Using transgenic tools to visualise Bmp signalling, Bmp expression, or mark clonogenic CNC cells, in combination with micro-computer tomography (µCT), Optical Projection Tomography (OPT), and confocal microscopy, we will visualize CNC cell migration, proliferation, and differentiation in relation to and dependence of Bmp7 in 3D. Functional embryology and gene/protein expression studies will identify the stages at which Bmp7 function is critical.  Cellular assays will allow testing of direct effects of Bmp7 on CNC explant cultures. Our aim is to define molecular and cellular processes dependant on Bmp7 and establish whether the many seemingly rather different cellular outcomes are the result of fundamental changes to cytoskeletal organization. This project provides exciting opportunities for graduate and undergraduate students to receive training in cutting-edge imaging and advanced transgenic technologies, embryology, histology, and gene expression analysis including next generation sequencing, as well as benefit from national and international collaborations.