Metabolic Organization by the Caveolae and Cytoskeleton

项目描述（由申请人提供）：本项目将研究细胞骨架和小泡在组织和调节代谢中的作用。几十年前，利用侵入性技术阐明了代谢途径，从而提出了细胞质是均匀的，本质上表现为“酶袋”的假设。随着具有更高空间分辨率和灵敏度的侵入性更小的技术的出现，细胞信号传导途径最近得到了研究，并且出现了一个非常不同的范式，即细胞结构对信号蛋白和小分子的定位很重要，细胞结构是细胞信号传导的关键调节成分。近年来，由于其在细胞信号传导调节中的作用，小泡受到了相当大的关注，然而，它们在细胞代谢中的作用仅被肤浅地研究过。小泡可能是糖酵解途径定位的一个位点，它允许在能量消耗过程（如离子运输）附近产生能量，并且可能对多种组织中胰岛素信号的特异性至关重要。已知细胞骨架定位糖酵解酶，但这种定位在糖酵解代谢的功能组织中的作用尚不清楚。因此，我们假设细胞骨架和小泡在血管平滑肌（VSM）代谢的组织和调节中起重要作用。本提案的目的是确定细胞骨架（肌动蛋白和微管蛋白）和小泡在VSM代谢结构中的作用。研究人员将验证以下假设：微管和肌动蛋白细胞骨架作为支架在细胞质内锚定糖酵解酶（特定目标1），糖酵解酶与这些结构的关联负责VSM代谢的组织/区室。研究人员还将验证糖酵解酶特异性定位于小泡区，而糖异生酶特异性定位于膜的非小泡区（特异性目标3），这些特异性关联负责VSM中代谢的组织（特异性目标4）。这些研究可能适用于各种各样的细胞类型，并将为VSM细胞中代谢组织的结构基础提供新的认识，并开始揭示代谢组织的功能后果，如有组织代谢在支持细胞功能中的作用。

DESCRIPTION (provided by applicant): This project will examine the role of the cytoskeleton and the caveolae in the organization and regulation of metabolism. The metabolic pathways were elucidated decades ago using invasive techniques and thus provided an assumption that the cytoplasm was uniform and essentially behaved as a "bag of enzymes". With less invasive techniques with higher spatial resolution and sensitivity, cell signaling pathways have recently been studied and a very different paradigm has arisen that cytoarchitecture is important for localization of signaling proteins and small molecules and that the cytoarchitecture is a key regulatory component for cell signaling. The caveolae have recently received considerable attention for their role in the regulation of cell signaling, however, their role in cell metabolism has been only superficially investigated. Caveolae are a likely site of glycolytic pathway localization which allows for the production of energy near energy-consuming processes such as ion transport and are likely critical to the specificity of insulin signaling in a variety of tissues. The cytoskeleton has been known to localize glycolytic enzymes but the role of such localization in the functional organization of glycolytic metabolism is not known. Therefore, we hypothesize that the cytoskeleton and the caveolae are important in the organization and regulation of vascular smooth muscle (VSM) metabolism. The aim of this proposal is to determine the role of the cytoskeleton (actin and tubulin) and caveolae in the structuring of metabolism in VSM. The investigators will test the hypothesis that microtubules and the actin cytoskeleton function as a scaffolding for anchoring glycolytic enzymes within the cytoplasm (specific aim 1) and that the association of glycolytic enzymes with these structures is responsible for the organization/compartmentation of metabolism in VSM. The investigators will also test the hypothesis that glycolytic enzymes are specifically localized to caveolae while gluconeogenic enzymes are specifically localized to non-caveolar regions of the membrane (specific aim 3) and that these specific associations are responsible for the organization of metabolism in VSM (specific aim 4). These investigations are likely applicable to a wide variety of cell types and will provide a new understanding of the structural basis for the organization of metabolism in VSM cells and begin to unveil the functional consequences of the organization of metabolism such as the role of organized metabolism in the support of cell function.