F31 Microtubule function in the onset of whole-body regeneration

项目摘要 组织再生是更新、恢复和生长的过程，使有机体能够重新生长 受伤后四肢和器官。组织再生能力存在于不同的生物体中，这表明它们 可能是古老的，所以了解控制再生的机制是很重要的。这个 淡水扁平线虫可以从几乎任何手术损伤中再生，包括 斩首，是理解动物再生的机制基础的一个模型。受伤后，组织 创口附近的信号传递给附近的成人多能干细胞，称为新生成骨细胞，这些干细胞分化以取代所有 缺失组织的细胞类型。高度保守的Wnt信号通路是控制再生所必需的 在脊椎动物再生中的前后部组织同一性。头对尾中最早的事件 测定是损伤诱导分泌的Wnt抑制物在前向选择性地表达 而不是面向后方的伤口。然而，引导这一对称破缺事件的机制是 未知。损伤诱导的NOT表达发生在体壁肌肉细胞胞体中 肌纤维纵向排列，提示肌细胞取向和极性在肌萎缩侧索硬化症发病中的作用。 再生。然而，调节这种极性的分子信号和结构是未知的，但经典的 对浮萍的小分子抑制研究表明，微管可能在这一过程中发挥了作用。的目标是 这个项目是为了揭示微管参与再生极性的机制。 在以下具体目标方面作出回应。AIM 1利用RNAi测试微管调节因子的作用 在肌肉中表达，以控制损伤诱导的基因在组织再生开始时的表达。AIM 2用途 用RNAi分析上位性以揭示运动蛋白微管运动蛋白与 用于头部和眼睛区域的WNT路径用于再生。这些实验将为我们提供关于 损伤诱导再生过程中微管的细胞和分子机制。我的结果将提供 对理解正确的伤害信号所需的其他因素并帮助形成更好的 理解是什么控制了极性。

Project Summary Tissue regeneration is the process of renewal, restoration and growth that allows an organism to re-grow limbs and organs after injury. Tissue regeneration abilities are present in diverse organisms, suggesting they may have been ancient, so the mechanisms controlling regeneration have been important to understand. The freshwater planarian flatworm Schmidtea mediterranea regenerates from nearly any surgical injury, including decapitation, and is a model for understanding the mechanistic basis of animal regeneration. After injury, tissue near wound sites signals to nearby adult pluripotent stem cells called neoblasts, which differentiate to replace all cell types of missing tissue. The highly conserved Wnt signaling pathway is essential for controlling regeneration of anterior-versus-posterior tissue identity in planarian regeneration. The earliest event in head versus tail determination is the injury induced expression of the secreted Wnt inhibitor notum selectively at anterior-facing and not posterior-facing wound sites. However, the mechanism directing this symmetry breaking event is unknown. Injury induced notum expression occurs from the soma of body wall muscle cells possessing longitudinally aligned muscle fibers, suggesting a role of muscle cell orientation and polarity in the onset of regeneration. However, the molecular signals and structure regulating this polarity are unknown, but classic small molecule inhibition studies in planaria suggest a possible role for microtubules in this process. The goal of this project is to uncover the mechanisms by which microtubules participate in the polarity of the regeneration response in the following specific aims. Aim 1 utilizes RNAi to test roles for microtubule regulatory factors expressed in muscle to control injury-induced gene expression at the onset of tissue regeneration. Aim 2 uses epistasis analysis with RNAi to uncover the mechanism by which a kinesin microtubule motor protein relates to a Wnt pathway for head and eye regionalization used in regeneration. These experiments will provide insight on the cellular and molecular mechanism of microtubules during injury induced regeneration. My results will provide new insights into understanding the other factors necessary for proper injury signal and help form a better understanding on what regulates polarity.