| Tracking Lipid Transfer by Fatty Acid Isotopolog Profiling from Host Plants to Arbuscular Mycorrhiza Fungi
|
|
Author:
Date:
2018-04-05
[Abstract] Lipid transfer from host plants to arbuscular mycorrhiza fungi was hypothesized for several years because sequenced arbuscular mycorrhiza fungal genomes lack genes encoding cytosolic fatty acid synthase (Wewer et al., 2014; Rich et al., 2017). It was finally shown by two independent experimental approaches (Jiang et al., 2017; Keymer et al., 2017; Luginbuehl et al., 2017). One approach used a technique called isotopolog profiling (Keymer et al., 2017). Isotopologs are molecules, which differ only in their isotopic composition. For isotopolog profiling an organism is fed with a heavy isotope labelled precursor metabolite. Subsequently, the labelled isotopolog composition of metabolic products is analysed via mass spectrometry. The ...
[摘要] 因为测序的丛枝菌根真菌基因组缺乏编码胞质脂肪酸合酶的基因（Wewer等人，2014; Rich等人，2014），因此假定脂质从宿主植物转移到丛枝菌根真菌数年。 / em>，2017）。最终通过两种独立的实验方法（Jiang等人，2017; Keymer等人，2017; Luginbuehl等人， ）， 2017年）。一种方法使用称为同位素体谱分析的技术（Keymer等人，2017）。同位素体是分子，它们的同位素组成不同。对于同位素生物学分析，生物体被喂以重同位素标记的前体代谢物。随后，通过质谱分析代谢产物的标记同位素组成。检测到的目标代谢物的同位素体模式产生关于代谢途径和通量的信息（Ahmed et al。，2014）。以下协议描述了一个实验装置，该装置能够在由丛枝菌根真菌及其相关真菌胞外菌丝体定植的植物根中分离出脂肪酸的单独同位素分布图，以阐明两种共生生物之间的通量。我们预测，如果两种相互作用的生物体可以物理分离，则该策略还可以用于研究其他生物体之间的代谢物通量。
【背景】丛枝菌根真菌是生物营养生物。因此，它们不能独立栽培，而是依靠与寄主植物的相互作用来维持生命并完成它们的生命周期。这一特征使得研究两种共生生物，特别是单独的真菌具有挑战性。
为了培养，处理和收获与宿主根分开的真菌，开发了2室培养皿系统，并将其用于以前工作中的标记研究（Bécard和Fortin，1988; ...
|
|
|
| Lipid Extraction from HeLa Cells, Quantification of Lipids, Formation of Large Unilamellar Vesicles (LUVs) by Extrusion and in vitro Protein-lipid Binding Assays, Analysis of the Incubation Product by Transmission Electron Microscopy (TEM) and by Flotation across a Discontinuous Sucrose Gradient
|
|
Author:
Date:
2016-10-20
[Abstract] Dissecting the interactions established between proteins and membranes in a given type of cells is not an easy task. Using a cell-free system of large unilamellar vesicles (LUVs) to analyze these interactions may help decipher these interactions and identify potential membrane deformations induced by the proteins incubated with these LUVs. This article describes the protocols for 1) extraction of total lipids from eukaryotic cells using the method developed by Bligh and Dyer (1959), 2) the quantification of glycerophospholipids by gas chromatography after methanolysis, followed by 3) the formation of LUVs by extrusion, 4) protein-lipid binding assay, 5) analysis of the incubation product by transmission electron microscopy (TEM) and by flotation across a discontinuous sucrose gradient and ...
[摘要] 解剖在给定类型的细胞中蛋白质和膜之间建立的相互作用不是一个容易的任务。使用大单层囊泡（LUV）的无细胞系统来分析这些相互作用可以帮助破译这些相互作用和识别由与这些LUV孵育的蛋白质诱导的潜在的膜变形。本文介绍了1）使用由Bligh和Dyer（1959）开发的方法从真核细胞中提取总脂质，2）在甲醇分解后通过气相色谱法定量甘油磷脂，然后3）通过挤出形成LUV的方案， 4）蛋白质 - 脂质结合测定，5）通过透射电子显微镜（TEM）和通过不连续蔗糖梯度浮选分析孵育产物，最后，6）通过免疫印迹分析蛋白质并通过碘素熏蒸显示甘油磷脂。
[背景] 包含巨单层囊泡（GUV;由单个磷脂双层组成，直径大于1μm）或脂质体孵育的无细胞系统与重组蛋白可能有助于了解这些相互作用。根据它们的直径和层数，脂质体被分为小的单层囊泡（SUV;由单个磷脂双层构成的囊泡，直径在20和100nm之间），大的单层囊泡（LUV;由单个双层磷脂，并且直径在100和400nm之间），大多层囊泡（MLV;由多个磷脂双层构成且直径在200nm和3μm之间的囊泡）和多泡囊泡（MVV）;由囊泡组成的大囊泡单个双层磷脂，并含有几个较小的囊泡，每个囊泡由单个双层磷脂组成）。 ...
|
|
|
| 13C Kinetic Labeling and Extraction of Metabolites from Adherent Mammalian Cells
|
|
Author:
Date:
2015-04-20
[Abstract] Fluctuations in metabolite levels in mammalian cells are the most direct form of readout of the cellular metabolic state. The current protocol describes a method for pulse labeling and subsequent isolation of metabolites from adherent mammalian cells. The isolated metabolites can be identified and quantified by mass-spectrometry, allowing for estimation of the rates of synthesis and removal of metabolites from the system being analyzed.
[摘要] 哺乳动物细胞中代谢物水平的波动是细胞代谢状态的最直接形式的读出。 当前的协议描述了用于脉冲标记和随后从贴壁哺乳动物细胞分离代谢物的方法。 分离的代谢物可以通过质谱法鉴定和定量，允许估计代谢物从所分析的系统的合成速率和去除速率。
|
|
|