Spectrin as a mechanosensitive hub integrating polarity, growth and trafficking

这个项目将增加我们对细胞如何协调其结构和生长的理解。细胞是生命的基本单位，具有由一组称为细胞骨架的内部结构蛋白质构建的确定形状。细胞也会生长、分裂，并感知它们的机械环境。 这些功能中的一些也依赖于细胞骨架蛋白。 在这个项目中，研究人员将研究血影蛋白，一个巨大的细胞骨架蛋白，在细胞生长，分裂和机械感应中发挥作用的机制。与这项研究相关联，主要研究者和她的团队将参与推广活动，促进干事业，包括在科学学院的努力，使一个移动的科学教室到宾夕法尼亚州中部/东部，并与当地的科学博物馆工作。这些活动将为K-12学生提供高影响力的STEM体验，并将教师专业发展带到农村和内城地区。主要研究者的实验室还将参与促进妇女，少数民族和LGBTQ+本科生参与研究的计划，并将研究项目纳入本科教学实验室，加强本科教育。细胞生长必须与细胞结构的机械性能相结合。spectrin是一种巨大的细胞骨架蛋白，具有两种截然不同的活性。它们最为人所知的是能够在细胞皮层与F肌动蛋白形成渔网状结构网络，可以进行机械拉伸。然而，血影蛋白最近也被证明可以调节内体系统中的蛋白质运输。平衡这两种活性的分子调节是未知的。通过对果蝇上皮细胞中β-H-血影蛋白的研究，本项目将验证两种相互竞争的假说，以阐明血影蛋白在细胞中协调机械感应和生长控制的分子机制。一种方法将测试的假设，紧张的血影蛋白网络中起着重要的作用，在搬迁的膜蛋白Crumbs和在其控制的生长抑制河马途径。第二种方法测试血影蛋白网络有助于调节Crumbs/Hippo控制核内体中细胞生长的假设。该项目将使用先进的STORM成像和蛋白质生物化学来确定血影蛋白网络的几何结构以及肌球蛋白II产生的张力变化对其拉伸的程度。蛋白质生物化学，遗传学和细胞生物学也将被用来进一步了解血影蛋白及其相关蛋白在内体蛋白质运输的调节作用。总的来说，这个项目的结果将产生新的模式，如何spectins功能在控制细胞growth.This奖项反映了NSF的法定使命，并已被认为是值得的支持，通过评估使用基金会的智力价值和更广泛的影响审查标准。

This project will increase our understanding of how cells coordinate their structure and their growth. Cells, which are the fundamental unit of life, have a defined shape built by a set of internal structural proteins known as the cytoskeleton. Cells also grow, divide, and sense their mechanical environment. Some of these functions are also dependent on cytoskeletal proteins. In this project, the researches will examine the mechanism by which spectrin, a giant cytoskeletal protein, performs its functions in cell growth, division and mechano-sensing. Associated with this research, the principle investigator and her team will engage in outreach activities that promote STEM careers including leading an effort in the College of Science to bring a mobile science classroom to central/eastern Pennsylvania and working with a local science museum. These activities will provide high-impact STEM experiences to K-12 students, as well as bring teacher professional development to rural and inner-city areas. The principle investigator’s lab will also participate in programs that promote women, minority and LGBTQ+ undergraduate participation in research, and bring research projects into undergraduate teaching laboratories, enhancing undergraduate education. Cellular growth must be integrated with the mechanical properties of cellular structures. Spectrins are giant cytoskeletal proteins with two contrasting activities. They are best known for their ability to form fishing net-like structural networks with F actin at the cell cortex that can undergo mechanical stretching. However, spectrins have recently also been shown to modulate protein trafficking in the endosome system. The molecular regulation that balances these two activities is unknown. Through the study of Beta-H-spectrin in epithelial cells of Drosophila melanogaster, this project will test two competing hypotheses to elucidate the molecular mechanisms by which spectrins coordinate mechanosensing and growth control in the cell. One approach will test the hypothesis that tension in the spectrin network plays a role in the relocation of the membrane protein Crumbs and in its control of the growth-inhibiting Hippo pathway. The second approach tests the hypothesis that spectrin networking contributes to the regulation of Crumbs/Hippo control of cell growth in endosomes. The project will use advanced STORM imaging and protein biochemistry to determine the geometry of the spectrin network and the extent to which it is stretched by changes in Myosin II-generated tension. Protein biochemistry, genetics and cell biology will also be used to further understand the role of spectrin and its associated proteins in the regulation of endosomal protein trafficking. Overall the results of this project will generate new paradigms for how spectrins function in the control of cellular growth.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.