Uncovering mechanisms and progenitors responsible for limb regeneration

项目摘要 截肢影响了近200万美国人，并伴有感染，疼痛和出血等并发症 血栓，除了严重的心理影响。目前，肢体丧失后的护理标准是使用 一个假肢。断肢后的理想反应是再生出与断肢完全相同的复制品。 失去了肢体这不是人类的反应，但其他物种，如蝾螈，有能力 完美再生失去的肢体因此，了解蝾螈的非凡能力， 再生失去的肢体可能阐明解锁人类再生能力的机制。以下 截肢蝾螈形成了一种叫做芽基的结构。芽基是一个组织特异性的 负责再生断肢的祖细胞。分子生物学的最新进展 从而发现了再生肢体所特有的基因。我们最近 鉴定了血管性血友病因子D和EGF结构域（VWDE）作为高度胚基富集和特异性的 基因我们假设芽基包含一个转录上不同的祖细胞和泛- 芽基基因，如VWDE，支持这一生态位。我们的第一个目标将评估的作用和功能域 VWDE在芽基细胞功能和哺乳动物细胞分化中的作用。我们的第二个目标是 其他祖细胞（即真皮、软骨、雪旺细胞），使用单细胞RNA测序来阐明 胚基的细胞异质性。这些研究将提供关于新基因的重要信息， 致力于揭示蝾螈肢体再生所需的不同祖细胞。这些收益在 对蝾螈肢体再生的理解将使我们更接近于解锁促进 人类的再生

PROJECT SUMMARY Limb loss affects nearly 2 million Americans and comes with complications such as infection, pain, and blood clots, in addition to serious psychological impact. Currently, the standard of care following limb loss is the use of a prosthetic. The ideal response following limb loss would be the regeneration of an exact replicate of the lost limb. This is not the response humans make, but other species such salamanders have the ability to perfectly regenerate lost appendages. Therefore, understanding the remarkable ability of salamanders to regenerate lost limbs may elucidate mechanisms to unlock the regenerative capacity of humans. Following limb amputation salamanders form a structure called the blastema. The blastema is a pool of tissue specific progenitor cells that are responsible for regenerating the lost limb. Recent gains in molecular biology has allowed for discovery of genes that are enriched and specific to the regenerating limb. We have recently identified von Willebrand Factor D and EGF domains (VWDE) as a highly blastema enriched and specific gene. We hypothesize that the blastema contains a pool of transcriptionally distinct progenitor cells and pan- blastemal genes, such as VWDE, support this niche. Our first aim will evaluate the role and functional domains of VWDE in blastema cell function and mammalian cell differentiation. Our second aim will work to uncover other progenitor cells (i.e. dermis, cartilage, Schwann cells) using single cell RNA-sequencing to elucidate the cellular heterogeneity of the blastema. These studies will provide essential information on a novel gene and work to uncover different progenitor cells required for limb regeneration in salamanders. These gains in understanding of salamander limb regeneration will put us closer to unlocking the ability to promote regeneration in humans.