TGF-β信号通路在脑血管发育和稳态维持中的生理功能及其机制

Our understanding concerning the genetic mechanism underlying the development and homeostasis of brain blood vessel and blood brain barrier (BBB) is very limited. Very few is known about whether there is TGF-β signaling pathway regulated long non-coding RNA (lncRNA) or microRNA (miRNA) in brain endothelial cell, and how they accurately modulate the cellular response to TGF-β signals and function during the development and homeostasis of brian blood vessel. This project will screen TGF-β regulated lncRNAs or miRNAs in brain endothelial cell by deep sequencing, using a mouse model of intraventricular hemorrhage and BBB breakdown caused by Smad4 disruption in brain endothelial cell. The function and mechanism of the TGF-β regulated lncRNAs or miRNAs in regulating proliferation, differentiation, cell transition, migration, apoptosis, and the interaction between endothelial cell and pericyte or astrocyte will be investigated. In addition, brain endothelial cell specific TGF-β regulated coding or non-coding RNA gene knockout mice will be developed. Detailed characterization of morphological and functional defects of brain vessels, endothelial cell differentiation, BBB integrity will be performed. The molecular mechanism underlying the physiological function of TGF-β regulated regulated coding or non-coding RNA gene will be studied. We would expect new mechanistic insights into the development and maintenance of the brain blood vessel and cerebrovascular disorders.

人类对脑血管和血脑屏障发育及稳态维持的遗传调控机制的认识相当有限,对脑血管内皮中是否存在受TGF-β信号通路调节的lncRNA和miRNA，以及它们如何精确调控对TGF-β的反应性并在脑血管和血脑屏障发育过程中发挥功能几乎一无所知。本项目将利用脑血管内皮Smad4基因敲除导致颅内出血和血脑屏障缺陷的小鼠模型，通过深度测序筛选脑血管内皮中受TGF-β通路调节的非编码RNA和调控基因,验证和评价它们影响脑血管内皮对TGF-β的反应性及其增殖、分化、细胞转化、迁移、凋亡、及与周细胞或神经胶质细胞相互作用等功能，并探索其分子机制。同时研制脑血管内皮特异性基因敲除小鼠，在生物整体水平、组织细胞水平和分子水平对突变小鼠脑血管表型系统分析，研究TGF-β通路调控基因和非编码RNA基因在脑血管和血脑屏障发育及稳态维持中的生理功能和分子机制，期望在脑血管发育和疾病的遗传调控机制方面有全新的认识。

本项目利用脑血管内皮Smad4基因敲除导致颅内出血和血脑屏障缺陷的小鼠模型，通过深度测序筛选脑血管内皮中受TGF-β通路调节的非编码RNA和调控基因。在体外研究了部分调控分子对脑血管内皮细胞TGF-β信号反应性及其功能的影响，并研制了8种新型脑血管内皮细胞特异性基因敲除小鼠。在生物整体水平、组织器官水平和分子水平对突变小鼠脑血管表型系统分析，并探索了相关的分子机制。研究揭示了脑血管内皮细胞通过维持乳酸稳态调节海马成体神经发生和认知功能的全新机制，证实脑血管内皮细胞PTEN/Akt信号通路通过MCT1调控乳酸的跨血管转运，进而调节海马成体神经发生以及学习认知功能。首次提供体内证据揭示了Hgs介导的ESCRT系统在维持脑血管内皮细胞极性和脑血管稳定性中的生理功能，并证实Hgs介导的ESCRT系统通过调控VE-cadherin的细胞内吞再循环过程维持脑血管内皮细胞极性。14篇研究论文和综述发表在Cell Stem Cell、Cardiovascular Research等专业杂志上。