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肢的能力有限， 包括指尖再生和骨折愈合。相比之下，斑马鱼可以再生整个 截肢后的附肢。与开发中一样，重新生成的附件也会适当缩放以 体型。广泛的遗传学和药理学实验已经建立了规范的信号 在损伤后，如成纤维细胞生长因子和Wnt等通路被重新激活，以促进细胞的增殖、迁移和 驱动附肢再生的分化。然而，这些通路如何编码大小和形状 目前还不清楚。这在一定程度上是由于对这些信号的定量和动态描述的数量有限 再生过程中的通路及其下游细胞事件。为了解决这些差距， 了解附属物在再生过程中的结垢情况，本建议旨在开发一种定量的、活的 斑马鱼尾鳍再生成像平台。具体地说，目标1将决定细胞外的作用 信号调节激酶(ERK)在鳍射线再生过程中编码细胞增殖和骨大小。目标2 将定义负反馈在鳍再生过程中的作用，并调查这种负反馈是否 有助于增强该再生事件的稳健性。总体而言，这项工作将建立一个量化的 用于探讨再生过程中大小和形状控制的细胞基础的模型。这项工作将是 在杜克大学迪塔利亚博士和波斯博士的指导下进行。这是一个高度协作的 提供数量生物学和再生生物学专业知识的培训环境。这项拟议的研究 将与量化方法、科学写作和指导方面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.