Integrating Cell Division and Morphogenesis in Vessels

描述(由申请人提供)： 为了生成替代血管，了解细胞过程是如何整合在体内组装血管是很有用的。然而，我们对这些集成链接的了解很少。血管形成是通过内皮细胞的活动进行的，包括细胞分裂和形态形成过程，如黏附和迁移。正常情况下，这些不同的过程被优雅地交织在一起，以产生适量的具有适当三维图案的血管。大多数血管生成剂激活同时影响分裂和形态发生的信号通路，但这是如何发生的还不完全清楚。这项工作将调查这些关系，并测试中心假设，即控制内皮细胞分裂与导致新血管的关键形态发生事件有关。这将使用动态图像分析来完成。将使用一种产生胚胎干细胞衍生血管的新小鼠模型，并将开发创新技术来分析四倍体胚胎和转基因小鼠外植体中的血管形成。其具体目标是：1)确定内皮细胞分裂和血管形态发生在时间和空间上是如何协调的；2)确定对细胞周期进行负面调节或阻止的调节因素是否会影响血管形态发生。携带定位于膜和核DNA的内皮特异性GFP的血管将被用于动态图像分析，以提供一组基线关系。然后，细胞周期调节因子将在内皮细胞中不适当地表达，并将使用动态成像来评估对形态发生的影响。这些操作将对野生型血管和由缺乏血管内皮生长因子(VEGF)受体Flt-1的细胞形成的突变血管进行。这项工作应该提供一个强大的框架，以开始了解细胞分裂和形态发生是如何在血管形成过程中整合的，这些信息对于重建治疗用途的过程至关重要。

DESCRIPTION (provided by applicant): To generate replacement blood vessels, it is useful to understand how cellular processes are integrated to assemble blood vessels in the body. However, our knowledge of these integrating links is sparse. Blood vessel formation occurs via the actions of endothelial cells that include both cell division and morphogenetic processes such as adhesion and migration. Normally these distinct processes are elegantly interwoven to produce the appropriate amount of vasculature with the proper 3-dimensional pattern. Most angiogenic agents activate signaling pathways that affect both division and morphogenesis, but how this occurs is not entirely clear. This work will investigate these relationships, and test the central hypothesis that control of endothelial cell division is linked to crucial morphogenetic events that result in new blood vessels. This will be done using dynamic image analysis. A novel murine model that produces embryonic stem cell-derived vessels will be used, and innovative technology will be developed to analyze vessel formation in explants of tetraploid embryos and transgenic mice as well. The specific aims are: 1) to determine how endothelial cell division and blood vessel morphogenesis are coordinated in time and space; and 2) to determine if regulators that negatively modulate or block the cell cycle affect blood vessel morphogenesis. Blood vessels carrying endothelial-specific GFP localized to both the membrane and nuclear DNA will be used for dynamic image analysis to provide a baseline set of relationships. Then cell cycle regulators will be inappropriately expressed in endothelial cells, and effects on morphogenesis will be evaluated using dynamic imaging. These manipulations will be done with both wild-type vessels and mutant vessels formed from cells lacking the vascular endothelial growth factor (VEGF) receptor flt-1. This work should provide a strong framework to begin to understand how cell division and morphogenesis are integrated during blood vessel formation, information critical to reconstituting the process for therapeutic uses.