Molecular and cellular mechanisms underlying the nerve dependence of regeneration

项目总结 细胞是生命的基石。组织和器官的功能产生于动态的属性和 细胞类型的相互作用。细胞类型和细胞状态的多样性，在从几分钟到 几千年来，动物的解剖和生理多样性奠定了基础。因为细胞多样性最终是 基因差异表达的结果，从细胞类型的角度研究生物生物学是必要的 将基因与动物生理学和病理学联系起来。我们研究计划的首要目标是 了解细胞类型的分子多样性和进化如何决定脊椎动物物种如何适应 不同于环境中的变化。我们把重点放在进化论观点具有 有可能揭示出可跨物种推广的基本原则。实验室的一小部分 研究细胞类型进化和行为进化之间的关系。实验室的大多数人 重点是再生，以阐明细胞类型在空间和时间上的动态相互作用如何导致 复杂组织和身体部位的再生，重点放在那些可能 在身体各部位和不同物种之间保持保守。 我们未来五年的目标是为这项研究计划奠定基础。具体来说，我们建议 进一步发展西班牙罗汉平菇作为再生的模式。乌罗代尔两栖动物 因为蝾螈是再生能力最强的陆生脊椎动物。Pleurodeles是一个优秀的 Aaxolotl是最流行的两栖动物再生模式的补充：(I)这两个物种 它们的比较可能揭示再生的基本原理；(Ii)与axolotl不同， 侧耳有一个完整的生活史，包括变态到真正的成虫阶段；(3)侧耳有 测序基因组，并建立转基因和基因组编辑的方法。 为了最大限度地发挥我们研究的影响并发现进化保守的机制，我们将专注于 再生的神经依赖性，几乎在每一个高度再生的物种中都能观察到这种现象 在各种组织中。具体地说，我们将比较大脑和肢体再生。首先，我们将确定 在这两种不同的环境中，再生是否依赖于相同的神经分泌蛋白。第二, 我们将阐明神经活动是否是调节神经对再生的影响所必需的。第三，我们 将破译神经信号如何诱导干细胞或祖细胞增殖。 影响：这项工作将揭示普遍存在于全身的分子和细胞再生机制 并为跨物种的比较研究奠定了基础。一般机制的发现 潜在的再生将阐明为什么包括人类在内的许多物种失去了再生能力，以及 可能会促进人类再生医学新方法的发展。

PROJECT SUMMARY Cells are the building blocks of life. The functions of tissues and organs emerge from the dynamic properties and interactions of cell types. The diversity of cell types and cellular states, over time scales ranging from minutes to millennia, underlies the anatomical and physiological diversity of animals. Because cellular diversity is ultimately the result of differential gene expression, studying organismal biology from a cell type perspective is necessary to link genes to animal physiology and pathology. The overarching goal of our research program is to understand how the molecular diversity and evolution of cell types determines how vertebrate species adapt differently to changes in their environment. We focus on problems where the evolutionary perspective has the potential to reveal fundamental principles that may generalize across species. A smaller part of the lab investigates the relationships between cell type evolution and the evolution of behavior. The majority of the lab focuses on regeneration, to elucidate how dynamic interactions of cell types in space and time result in the regeneration of complex tissues and body parts, with an emphasis on those cell types and interactions that might be conserved across body parts and species. Our goal for the next five years is to lay the foundations of this research program. Specifically, we propose to develop further the Spanish ribbed newt Pleurodeles waltl as a model for regeneration. Urodele amphibians such as newts are the terrestrial vertebrates with the highest regenerative capacity. Pleurodeles is an excellent complement to axolotl, the most popular amphibian model for regeneration: (i) these two species diverged about 150 million years ago, and their comparison may reveal fundamental principles of regeneration; (ii) unlike axolotl, Pleurodeles has a complete life cycle, including metamorphosis into a true adult stage; (iii) Pleurodeles has a sequenced genome and established methods for transgenesis and genome editing. To maximize the impact of our research and discover evolutionarily conserved mechanisms, we will focus on the nerve dependence of regeneration, a phenomenon observed in almost every highly-regenerative species and in a variety of tissues. Specifically, we will compare brain and limb regeneration. First, we will determine whether regeneration depends on the same neural secreted proteins in these two different contexts. Second, we will clarify whether neural activity is necessary to mediate the effects of nerves on regeneration. Third, we will decipher how neural signals induce the proliferation of stem or progenitor cells. Impact: this work will reveal molecular and cellular mechanisms of regeneration that generalize across body parts, and lay the foundation for comparative studies across species. The discovery of general mechanisms underlying regeneration will clarify why many species, including humans, have lost regenerative capacity, and may catalyze the development of new approaches for human regenerative medicine.