kT-scale Protein & Carbohydrate Interactions on Synthetic Materials & Cell Surfaces

Pi：Bevan，Michael A.提案编号：1402739机构：约翰霍普金斯大学标题：KT尺度的蛋白质和碳水化合物在合成材料和细胞表面的相互作用许多重要的细胞相互作用涉及“弱”相互作用，这是目前技术难以描述的。PI建议进入新的领域，通过使用由PI的团队开发的扩散胶体探针显微镜(DCPM)来直接表征生物分子的这些弱分子间相互作用。该提案将研究两个具有生物学重要性的系统，这两个系统也因其对生物医学问题的重要性而被选中：基于干细胞的组织工程和癌症转移。弱生物相互作用研究技术的成功将影响对细胞间黏附、细胞迁移、组织形态发生、转移、免疫学等细胞过程中相互作用的理解，在细胞间黏附、细胞迁移、组织形态发生、转移、免疫等细胞过程中，弱生物分子相互作用起着重要的作用。虽然有测量强相互作用(PN力)的标准力学方法，但弱相互作用通常是通过光谱手段间接测量的。PI建议进入新的领域，通过使用DCPM直接描述这些相互作用，DCPM提供了空间和时间分辨率、统计意义和使用扫描探针或光谱方法无法获得的直接性。本质上，DCPM被动地监测“扩散探针”的布朗漂移，并在询问蛋白质和碳水化合物的相互作用时利用这些自然测量来测量时间(a2/D)、能量(KT)、力(Fn)和长度(Nm)。这本质上是一种纳米技术，因为它利用布朗运动作为一种有用的工具来直接测量蛋白质之间的KT相互作用，而不是避免随机热运动作为纳米系统的一种不受欢迎的复杂情况。将研究两个系统，CD44-HA相互作用和(在有钙离子存在的情况下)支持的双层上的异亲钙粘附素相互作用。DCPM用于研究弱生物相互作用的发展将影响对细胞-细胞黏附、细胞迁移、组织形态发生、转移、免疫学等细胞过程中这种相互作用的理解。

PI: Bevan, Michael A. Proposal Number: 1402739Institution: Johns Hopkins University Title: kT-scale Protein & Carbohydrate Interactions on Synthetic Materials & Cell Surfaces Many important cellular interactions involve "weak" interactions, which are difficult to characterize by current techniques. The PI proposes to move into new territory, in terms of directly characterizing these weak intermolecular interactions of biomolecules, by using a technique, Diffusing Colloidal Probe Microscopy (DCPM), developed by the PI's group. The proposal will examine two systems of biological importance, which were also chosen for their significance to biomedical problems: stem-cell based tissue engineering and cancer metastasis. Success in the development of the technique for studying weak biological interactions will have an impact on the understanding of such interactions in cell-cell adhesion, cell migration, tissue morphogenesis, metastasis, immunology, and other cellular processes.Weak biomolecular interactions, on the order of kT, play an important role in cell-cell adhesion, cell migration, tissue morphogenesis, metastasis, immunology, and other cellular processes. While there are standard mechanical methods for measuring strong interactions (pN forces), weak interactions are generally measured_ indirectly_ by spectroscopic means. The PI proposes to move into new territory, by directly characterizing these interactions using DCPM, which offers spatial and temporal resolution, statistical significance, and directness not accessible using scanning probes or spectroscopic methods. In essence, DCPM passively monitors Brownian excursions of "diffusing probes" and exploits these natural gauges for time (a2/D), energy (kT), force (fN), and length (nm) when interrogating the interaction of proteins and carbohydrates. This is inherently a nanoscale technique because it harnesses Brownian motion as a useful tool to directly measure kT interactions between proteins rather than avoiding stochastic thermal motion as an undesirable complication of nanoscale systems. Two systems will be studied, CD44-HA interactions and heterophilic cadherin interactions (in the presence of calcium ions) on supported bilayers. The development of DCPM for studying weak biological interactions will have an impact on the understanding of such interactions in cell-cell adhesion, cell migration, tissue morphogenesis, metastasis, immunology, and other cellular processes.