Quantitative dissection of the events that encode bone size and shape during regeneration

摘要 哺乳动物在创伤和截肢后再生附属物的能力有限， 包括再生指尖和愈合骨折。相反，斑马鱼可以再生整个 截肢后的肢体在开发中，再生的附属物被适当地缩放， 体型广泛的遗传学和药理学实验已经证实， 损伤后，Fgf和Wnt等通路被重新激活，促进细胞增殖、迁移和凋亡。 分化驱动再生的附属物。然而，这些通路如何编码大小和形状， 还不清楚这部分是由于这些信号的定量和动态描述数量有限 再生过程中的信号通路及其下游细胞事件。为了解决这些差距， 了解附件缩放在再生过程中，这项建议的目的是制定一个定量的，活的 斑马鱼尾鳍再生成像平台。具体来说，目标1将确定细胞外的作用， 信号调节激酶（ERK）在鳍条再生过程中编码细胞增殖和骨大小。目的2 将定义负反馈在鳍再生过程中的作用，并研究这种负反馈是否 有助于该再生事件的鲁棒性。总的来说，这项工作将建立一个定量的 模型用于询问再生过程中大小和形状控制的细胞基础。这项工作将 在杜克大学进行的指导下，迪塔利亚博士和博士波斯。这是一个高度合作的 提供定量和再生生物学专业知识的培训环境。这项拟议的研究 将与定量方法，科学写作和导师制的重点培训一起进行。

ABSTRACT Mammals possess a limited compacity to regenerate appendages following traumatic injury and amputation, including regenerating digit tips and healing of bone fractures. In contrast, zebrafish can regenerate entire appendages following amputation. As in development, regenerated appendages are scaled appropriately to body size. Extensive genetic and pharmacological experiments have established that canonical signaling pathways, such as Fgf and Wnt, are reactivated following injury to promote the cell proliferation, migration, and differentiation that drives regeneration of appendages. However, how these pathways encode size and shape is unclear. This is due, in part, to the limited number of quantitative and dynamic descriptions of these signaling pathways and their downstream cellular events during regeneration. To address these gaps in the understanding of appendage scaling during regeneration, this proposal aims to develop a quantitative, live imaging platform for zebrafish caudal fin regeneration. Specifically, Aim 1 will determine the role of extracellular signal-regulated kinase (ERK) in encoding cell proliferation and bone size during fin ray regeneration. Aim 2 will define the role of negative feedback during fin regeneration and investigate whether this negative feedback contributes to the robustness of this regeneration event. Collectively, this work will establish a quantitative model for interrogating the cellular basis of size and shape control during regeneration. This work will be conducted at Duke University under the mentorship of Dr. Di Talia and Dr. Poss. This is a highly collaborative training environment that affords expertise in quantitative and regenerative biology. This proposed research will be carried out alongside focused training in quantitative approaches, scientific writing, and mentorship.