EH-DOMAIN FROM EHD-1

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得主要资金， 因此可以在其他CRISP条目中表示。列出的机构是 研究中心，而研究中心不一定是研究者所在的机构。 主要目的是解决C-末端Eps 15同源结构域（EHD）蛋白EHD 1的EH-结构域的结构。因此，我们将确定它如何调节整合素和信号受体在质膜上的内吞转运和再循环，并评估EHD 1对有丝分裂的影响。异常细胞增殖的一个关键原因是定位于质膜的受体对有丝分裂信号的不受抑制的转导。生长因子受体的内化导致刺激信号的减弱，而内吞作用中的受体缺陷诱导延长的促有丝分裂作用。内吞运输机制的破坏预计会影响细胞增殖并导致癌症。最近的研究也开始讨论β 1整合素的内吞行程，β 1整合素是与细胞外基质相互作用的关键受体，并协调生长因子受体信号，最终导致基因表达、增殖和运动，EHD 1是内吞转运和再循环的核心参与者，我们最近证实了受损的b1整合素再循环和定位于肿瘤细胞。质膜以及下游事件，包括在缺乏EHD 1的情况下的细胞铺展和迁移（Jovic等，提交的手稿，附录I）。因此，EHD 1的缺失和/或其与调节内吞机制的蛋白质网络的相互作用破坏了正常的细胞功能，理解EHD 1的EH-结构域与这些调节蛋白相互作用的分子基础是该提议的关键目标。我们实验室的研究发现了EH结构域的一个新功能：直接与肌醇磷脂结合。然而，EH-结构域相互作用的模式尚未确定。这项合作研究将使我们能够通过基于NMR的EHD 1 EH结构域结构的解决方案来阐明EHD 1功能的分子机制，并为这一关键蛋白的功能及其对整合素的调控提供新的见解。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The main objective is to solve the structure of the EH-domain of the C-terminal Eps15 homology domain(EHD) protein, EHD1. We shall thus determine how it regulates endocytic transport and recycling of integrinand signaling receptors at the plasma membrane, and assess the impact of EHD1 on mitogenesis.A key cause of aberrant cell proliferation is the unchecked transduction of mitogenic signals by receptorslocalized to the plasma membrane. The internalization of growth factor receptors leads to attenuation ofstimulatory signals and receptors defective in endocytosis induce prolonged mitogenic effects. Subversion ofthe endocytic trafficking machinery is predicted to affect cell proliferation and lead to cancer. Recent studieshave also begun to address the endocytic itineraries of beta1 integrins, key receptors that interact with theextracellular matrix and coordinately transduce growth factor receptor signals that culminate in geneexpression, proliferation, and motility, thereby directly influencing cancer and metastatic potential.EHD1 is a central player in endocytic transport and recycling and we have recently demonstrated impairedb1 integrin recycling and localization to the plasma membrane as well as downstream events including cellspreading and migration in the absence of EHD1 (Jovic et al, manuscript submitted, Appendix I).Accordingly, the loss of EHD1 and/or its interactions with the network of proteins that regulate the endocyticmachinery disrupts normal cell function, and understanding the molecular basis by which the EH-domain ofEHD1 interacts with these regulatory proteins is a key goal of this proposal. Research in our laboratory hasidentified a novel function for EH-domains: direct binding to inositol phospholipids. However, the mode bywhich EH-domains interaction partners has yet to be determined. The proposed collaborative study will allowus to elucidate the molecular mechanisms of EHD1 function by NMR-based solution of the EHD1 EH-domainstructure, and provide novel insights into the functioning of this key protein and its regulation of integrins.