Syndecan-1 in Mechanosensing of Engineered Microenvironments

血管系统的细胞对来自所施加的力的生物物理线索是独特敏感的， 它们的细胞微环境在用于血管治疗或用于输送 细胞，一个关键的挑战是了解细胞用来感知生物物理线索的机制， 他们的环境，使更有效的治疗。多配体聚糖是蛋白聚糖， 用硫酸乙酰肝素糖胺聚糖链修饰的蛋白质核心。由于他们的存在， 细胞表面及其与细胞骨架和粘着斑相关分子的相互作用， 表面蛋白聚糖的位置非常适合作为细胞的机械传感器 微环境我们的研究小组最近发现syndecan-1（SDC 1）调节血管平滑肌 肌细胞分化和内皮细胞对剪切应力的反应。我们假设 SDC 1是基质介导的信号的机械传感器，可以靶向改变内皮细胞的功能。 生物材料相互作用，以更好地控制这些工程材料上的细胞功能。在目标1中，我们 检查SDC 1在调节底物的血管机械感受中的机制作用 顺应性和纳米拓扑学。我们将创建表达改变的内皮细胞系， SDC 1中的突变，并确定这些改变如何影响工程机械传感。 具有不同顺应性和纳米形貌的基底。具体来说，我们将研究 SDC 1通过包括Hippo途径在内的途径调节机械介导的信号传导， TGF-β和Rho-GTP酶。此外，我们还将研究表型调节和内皮细胞- 在存在生物化学物质的情况下，内皮细胞在这些基质上的间质转化 治疗。在目标2中，我们将开发一种新型的基于FRET的分子力生物传感器， 我们来检查在活细胞与工程化细胞相互作用期间施加于SDC 1的力。 印刷受体.这种生物传感器将使我们能够探测分子亚结构域的重要性， SDC 1在机械传感中的作用，包括糖基化位点和胞质结构域。在一起， 我们的研究结果将有助于我们理解细胞的机械转导，并提供所需的 开发改进的血管装置和细胞输送支架的知识。

The cells of the vascular system are uniquely sensitive to biophysical cues from applied forces and their local cellular microenvironment. In engineering materials for vascular therapies or for delivery of cells, a key challenge is to understand the mechanisms that cells use to sense biophysical cues from their environment to enable more effective therapies. Syndecans are proteoglycans that consist of a protein core modified with heparan sulfate glycosaminoglycan chains. Due to their presence on the cell surface and their interaction with cytoskeletal and focal adhesion associated molecules, cell surface proteoglycans are ideally located to serve as mechanosensors of the cellular microenvironment. Our group recently found that syndecan-1 (SDC1) regulates vascular smooth muscle cell differentiation and the response to shear stress in endothelial cells. We hypothesize that SDC1 is a mechanosensor for substrate-mediated cues and can be targeted to alter endothelial cell- biomaterial interactions to better control cell function on these engineered materials. In Aim 1, we will examine the mechanistic role of SDC1 in regulating vascular mechanosensing of substrate compliance and nanotopology. We will create endothelial cell lines with altered expression or mutation in SDC1 and determine how these alterations affect mechanosensing on engineered substrates with varying compliance and nanotopology. Specifically, we will investigate the ability of SDC1 to regulate mechanically mediated signaling through pathways including the Hippo pathway, TGF-β and Rho-GTPases. In addition, we will examine phenotypic regulation and endothelial-to- mesenchymal transition of endothelial cells on these substrates in the presence of biochemical treatments. In Aim 2, we will develop a novel, FRET-based molecular force biosensor that will enable us to examine the forces that are applied to SDC1 during interactions of live cells with the engineered substrates. This biosensor will enable us to probe the importance of the molecular subdomains of SDC1 in mechanosensing, including the glycosylation sites and the cytoplasmic domains. Together, our findings will contribute to our understanding of cellular mechanotransduction and provide needed knowledge for the development of improved vascular devices and cell delivery scaffolds.