Regulation of Eye Regrowth in Xenopus laevmis

项目摘要 再生领域的一个主要挑战是确定信号通路和合适的再生途径。 组织修复所需的细胞类型对于眼睛来说，成功的一代和 维持眼睛特异性干细胞是一个关键目标。虽然脊椎动物眼睛的发育过程 经过充分研究和表征，损伤后可诱导眼干细胞增殖的机制 或疾病仍然难以识别。这部分是因为自然干细胞增殖通常发生在 在胚胎发育过程中，而视网膜再生的研究主要利用成人（或成熟） 模型-一个非常不同的环境。爪蟾（Xenopus laevis）是一种具有高度再生能力的爪蛙， 建立了发育和器官再生的模型。它也与人类密切相关。我们 非洲爪蟾的胚胎在5天内成功地重新长出了功能正常的眼睛。我们的研究还显示 成功的眼睛再生需要增加和延长视网膜干细胞增殖， 新的眼睛形成。调节眼睛再生的一个候选途径是生物电信号。生物电 信号传导的特征在于其在肢体再生中的作用，但其在眼睛发育和再生中的作用 还不清楚我们的数据显示，生物电信号的抑制会阻止眼睛的再生，这表明其 功能是必需的。我们试图理解和定义生物电信号在眼 再生，作为建立有效解剖相似性的协议的第一步， 发展与修复的区别这个项目将：1）定义表达模式和键 生物电信号成分在眼睛再生和发育过程中的作用; 2）评估 在激活再生视网膜祖细胞增殖和扩增中的生物电信号传导，和3） 确定潜在下游目标。总之，这项提案将利用非洲爪蟾独特的生物学特性， 建立一种有效的策略，以快速确定调节再生诱导视网膜的关键机制， 体内祖细胞增殖。该协议将为最终构建一个蓝图奠定基础， 有效的眼部修复策略。

PROJECT SUMMARY A main challenge in the regeneration field has been to identify the signaling pathways and suitable cell types needed to enable productive tissue repair. For the eye, the successful generation and maintenance of eye-specific stem cells is a key goal. Although the process of vertebrate eye development is well-studied and characterized, the mechanisms that can induce eye stem cell proliferation following injury or disease remain difficult to identify. This is partly because natural stem cell proliferation typically occurs during embryo development whereas studies of retinal regeneration have largely utilized adult (or mature) models – a very different environment. The highly regenerative clawed frog, Xenopus laevis, is an established model for both development and organ regeneration. It is also closely related to humans. We found that Xenopus embryos successfully regrew functional eyes within 5 days. Our studies also showed that successful eye regrowth required increased and extended retinal stem cell proliferation while delaying new eye formation. One candidate pathway to regulate eye regrowth is bioelectrical signaling. Bioelectrical signaling is well-characterized for its role in limb regeneration but its role in eye development and regrowth is unclear. Our data showed that inhibition of bioelectrical signaling blocked eye regrowth, indicating that its function is required. We seek to understand and define the roles of bioelectrical signaling during eye regrowth, as a first step towards establishing a protocol for effectively dissecting the similarities and distinctions between development and repair. This project will: 1) define the expression patterns and key function of bioelectrical signaling components during eye regrowth and development; 2) assess the role of bioelectrical signaling in activating regenerative retinal progenitor cell proliferation and expansion, and 3) identify potential downstream targets. Together, this proposal will leverage the unique biology of Xenopus to establish an efficient strategy to rapidly define key mechanisms that regulate regrowth-induced retinal progenitor cell proliferation in vivo. This protocol will set the foundation for eventually building a blueprint for productive eye repair strategies.