| Peroxisome Motility Measurement and Quantification Assay
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Author:
Date:
2017-09-05
[Abstract] Organelle movement, distribution and interaction contribute to the organisation of the eukaryotic cell. Peroxisomes are multifunctional organelles which contribute to cellular lipid metabolism and ROS homeostasis. They distribute uniformly in mammalian cells and move along microtubules via kinesin and dynein motors. Their metabolic cooperation with mitochondria and the endoplasmic reticulum (ER) is essential for the β-oxidation of fatty acids and the synthesis of myelin lipids and polyunsaturated fatty acids. A key assay to assess peroxisome motility in mammalian cells is the expression of a fluorescent fusion protein with a peroxisomal targeting signal (e.g., GFP-PTS1), which targets the peroxisomal matrix and allows live-cell imaging of peroxisomes. Here, we first present a ...
[摘要] 细胞器运动，分布和相互作用有助于真核细胞的组织。过氧化物酶体是有助于细胞脂质代谢和ROS稳态的多功能细胞器。它们在哺乳动物细胞中均匀分布，并通过驱动蛋白和动力蛋白电动机沿微管移动。他们与线粒体和内质网（ER）的代谢合作对脂肪酸的β-氧化和髓鞘脂质和多不饱和脂肪酸的合成至关重要。评估哺乳动物细胞中过氧化物酶体运动性的关键测定是具有过氧化物酶体靶向信号（例如GFP-PTS1）的荧光融合蛋白的表达，其靶向过氧化物酶体基质并允许过氧化物酶体的活细胞成像。在这里，我们首先提出了用过氧化物酶体标记物EGFP-SKL转染培养的哺乳动物细胞的方案，以观察活细胞中的过氧化物酶体。这种方法揭示了过氧化物酶体的不同运动行为和对过氧化物酶体膜动力学的新见解（Rapp等，1996; Wiemer等，1997; ...
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| Reversible Cryo-arrests of Living Cells to Pause Molecular Movements for High-resolution Imaging
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Author:
Date:
2017-04-20
[Abstract] Fluorescence live-cell imaging by single molecule localization microscopy (SMLM) or fluorescence lifetime imaging microscopy (FLIM) in principle allows for the spatio-temporal observation of molecular patterns in individual, living cells. However, the dynamics of molecules within cells hamper their precise observation. We present here a detailed protocol for consecutive cycles of reversible cryo-arrest of living cells on a microscope that allows for a precise determination of the evolution of molecular patterns within individual living cells. The usefulness of this approach has been demonstrated by observing ligand-induced clustering of receptor tyrosine kinases as well as their activity patterns by SMLM and FLIM (Masip et al., 2016).
[摘要] 通过单分子定位显微镜（SMLM）或荧光寿命成像显微镜（FLIM）的荧光活细胞成像原理上允许在个体，活细胞中的分子模式的时空观察。然而，细胞内分子的动力学阻碍了它们的精确观察。我们在这里介绍一个详细的方案，用于显微镜上活细胞可逆冷冻停滞的连续循环，允许精确测定各个活细胞内分子模式的演变。通过观察受体酪氨酸激酶的配体诱导的聚集以及SMLM和FLIM的活性模式已经证明了该方法的有用性（Masip等人，2016）。
了解细胞中的分子过程，例如受体 - 酪氨酸激酶（RTK）的配体诱导反应需要精确的时空观察分子模式。由于细胞状态的差异，这种反应需要在个体细胞而不是细胞群体中进行监测（Snijder和Pelkmans，2011）。使用SMLM，各个分子可以以高精度进行定位（Betzig等人，2006）。这允许例如提取关于质膜中的RTK聚类的信息。互补地，共焦FLIM可以揭示分子如何在衍射受限体积元素内作为整体反应。这可以通过使用构象传感器揭示RTK与下游分子的相互作用模式，磷酸化模式以及活性模式（Offterdinger等人，2004; Sabet等人）。 ...
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| Signaling Assays for Detection of Human G-protein-coupled Receptors in Yeast
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Author:
Date:
2014-08-20
[Abstract] G-protein-coupled receptors (GPCRs) are the largest group of cell-surface proteins and are major molecular targets for drug development. The protocol described herein is for the detection of human GPCR signaling in the yeast Saccharomyces cerevisiae. Using Zoanthus sp. green fluorescent protein (ZsGreen) as the reporter, engineered yeast cells expressing human GPCRs emit strong fluorescence in response to stimuli leading to receptor signal activation. This assay method would allow screening for agonistic ligands and critical mutations required for human GPCR signaling.
[摘要] G蛋白偶联受体（GPCR）是最大的细胞表面蛋白质组，是药物开发的主要分子靶标。 本文所述的方案用于在酵母酿酒酵母中检测人GPCR信号传导。 使用 Zoanthus 绿色荧光蛋白（ZsGreen ）作为报告物，表达人GPCR的工程化酵母细胞响应于导致受体信号活化的刺激而发射强荧光。 该测定方法将允许筛选激动剂配体和人GPCR信号传导所需的关键突变。
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