一，视觉画面和反向遗传方法来确定角质层的突变体。 角质层在模式植物拟南芥突变体被称为“eceriferum”的突变体，这意味着“不轴承蜡”。他们可以在视觉屏幕，也就是说，只是在寻找突变，你可以看到，野生型植株的花序干发白，而突变体深绿色有光泽的茎。是在这种类型的视觉画面隔离的突变体之一，这是一个叫做eceriferum4或cer4。 发现有趣的角质层突变体的另一种方法是用反向遗传学方法：利益选择的候选基因，然后该基因研究植物线路中断。这些突变TDNA扰乱感兴趣的基因，在这种情况下，细胞色素P450，我们现在所说的MAH1。 PCR检测结果（如在视频中显示的）可以确认，TDNA插入感兴趣的基因。当两个基因特异引物用于扩增野生型DNA，我们看到一个产品，但如果TDNA中断，在这种突变，有没有产品。相反，使用具体TDNA和基因的引物，只看到一个产品是在突变。我们期待为纯合子突变线，双方的母亲和父亲的基因副本都被打乱。如果一个基因副本是扰乱TDNA和其他副本仍然是野生型的PCR结果好坏参半。 二。使用气相色谱法确定Cutlicle蜡的化学成分。 我们分析使用气相色谱蜡的化学成分。首先，可溶性蜡化合物是从植物表面，在氯仿中浸泡。 然后，样品注入气相色谱列，他们将在那里被加热，并通过气体流发送。坚持或多或少不同的化合物之列的墙壁，分离的化合物，和他们出来后，在色谱柱的另一端，其他之一。那么，作为化合物的火焰离子化检测通过，我们看到的高峰。中的各峰的保留时间的特点是不同的化合物，质谱，我们已经确定拟南芥蜡的组成部分。目前的主要山峰C29正构烷烃，C29酮和C29仲醇。小峰的二级醇，脂肪酸，醛类和酯类。根据峰面积，相对标准，告诉我们多少每种化合物存在。 在从这些角质层突变体的气体色谱时，人们可以看到如何cer4缺乏主要的醇类和酯类，而mah1缺乏二级醇酮。这些表型可以告诉我们很多有关的功能基因在植物的兴趣。例如，我们才知道在cer4一线的基因突变，表型告诉我们，在伯醇的生物合成途径分支问题。后在孔斯特实验室研究该基因的分子身份，它被发现，它的脂肪酰基还原酶的基因家族，这正好与此化学表型的一部分​​。 三。使用的Cryo - SEM确定角质层的晶体结构当我们研究的拟南芥角质层突变体，我们可以看到，如果他们有深绿色，有光泽的表型或野生型干发白外观。我们用扫描电子显微镜看在植物表面的角质层和识别的视觉表型​​的基础上。我们利用低温扫描电镜，冻结的植物和观看他们在液氮温度下，为了保持角质层的完整，因为SEM需要真空操作，并没有使他们冻结，样品将干出和折叠。 这里cer4和mah1样品，与野生型控制，是解剖和冷冻的扫描电镜存根上。当样品被转移到显微镜的冷阶段，你可以看到，野生型拟南芥茎角质层的表面晶体覆盖。这是光散射这些晶体，使干发白外观。这里是cer4干;记得它看起来有光泽？它没有表面上的晶体。 人们曾做过实验，他们隔离纯蜡化合物从一种植物的角质层，当他们在实验室中重结晶，晶体形成的植物上发现相同的形状。在拟南芥中，我们相信晶体化合物的混合物，情况比较复杂。例如，化学分析显示，在cer4，只有轻微的伯醇及其衍生酯组成部分丢失，但对行政长官的晶体R4干都没有了。 mah1情况下，细胞色素P450酶基因突变的影响，突变株缺乏蜡，二级醇类及酮类的两个主要组成部分，但对mah1植物的晶体形式通常。 要了解更多有关拟南芥角质层突变体， <a href="http://arjournals.annualreviews.org/doi/abs/10.1146/annurev.arplant.59.103006.093219" target="_blank">请去植物生物学</a>的年度审查。

use of arabidopsis eceriferum mutants to explore plant cuticle biosynthesis

植物角质层蜡质覆盖在植物上，有一个节约用水的主要作用外，也是对病原微生物的入境重要屏障。角质层是由所谓的“角质”一个艰难的交联聚合物和保护蜡层密封植物表面。许多植物的角质层的蜡质层明显，出现的常春藤叶上的一个闪亮的电影或作为一个尘土飞扬的的葡萄或白菜叶感谢蜡光散射晶体表面上的外壳。由于角质层是植物必需适应地面环境，了解植物角质层的形成有关的基因已应用在农业和林业。今天，我们将展示植物角质层的正向和反向遗传学方法确定突变体的分析。

Watch this Scientific Journal Video about Use of Arabidopsis eceriferum Mutants to Explore Plant Cuticle Biosynthesis at JoVE.com

Use of Arabidopsis eceriferum Mutants to Explore Plant Cuticle Biosynthesis

植物角质层蜡质植物的外壳，在节约用水的主要作用，但也是对病原微生物的入境重要屏障。在这段视频中，我们展示了正向和反向遗传学方法所确定的植物角质层突变体的分析。

使用拟南芥eceriferum突变体探索植物角质层的生物合成

The plant cuticle is a waxy outer covering on plants that has a primary role in water conservation, but is also an important barrier against the entry of ...

use-arabidopsis-eceriferum-mutants-to-explore-plant-cuticle

Research

JoVE Journal

Biology

12.8K 次观看.  University of British Columbia - UBC. 植物角质层蜡质植物的外壳，在节约用水的主要作用，但也是对病原微生物的入境重要屏障。在这段视频中，我们展示了正向和反向遗传学方法所确定的植物角质层突变体的分析。

视频: Use of Arabidopsis eceriferum Mutants to Explore Plant Cuticle Biosynthesis

Efficient and Rapid Isolation of Early-stage Embryos from Arabidopsis thaliana Seeds

In flowering plants, the embryo develops within a nourishing tissue - the endosperm - surrounded by the maternal seed integuments (or seed coat). As a consequence, the isolation of plant embryos at early stages (1 cell to globular stage) is technically challenging due to their relative inaccessibility. Efficient manual dissection at early stages is strongly impaired by the small size of young Arabidopsis seeds and the adhesiveness of the embryo to the surrounding tissues. Here, we describe a method that allows the efficient isolation of young Arabidopsis embryos, yielding up to 40 embryos in 1 hr to 4 hr, depending on the downstream application. Embryos are released into isolation buffer by slightly crushing 250-750 seeds with a plastic pestle in an Eppendorf tube. A glass microcapillary attached to either a standard laboratory pipette (via a rubber tube) or a hydraulically controlled microinjector is used to collect embryos from droplets placed on a multi-well slide on an inverted light microscope. The technical skills required are simple and easily transferable, and the basic setup does not require costly equipment. Collected embryos are suitable for a variety of downstream applications such as RT-PCR, RNA sequencing, DNA methylation analyses, fluorescence in situ hybridization (FISH), immunostaining, and reporter gene assays.

Efficient and Rapid Isolation of Early-stage Embryos from Arabidopsis thaliana Seeds

We report an efficient and simple method to isolate embryos at early stages of development from Arabidopsis thaliana seeds. Up to 40 embryos can be isolated in 1 hr to 4 hr, depending on the downstream application. The procedure is suitable for transcriptome, DNA methylation, reporter gene expression, immunostaining and fluorescence in situ hybridization analyses.

高效，快速的早期胚胎分离<em&gt;拟南芥</em&gt;种子

In flowering plants, the embryo develops within a nourishing tissue - the endosperm - surrounded by the maternal seed integuments (or seed coat). As a ...

科研

生物学

Metabolic Labeling and Membrane Fractionation for Comparative Proteomic Analysis of Arabidopsis thaliana Suspension Cell Cultures

Plasma membrane microdomains are features based on the physical properties of the lipid and sterol environment and have particular roles in signaling processes. Extracting sterol-enriched membrane microdomains from plant cells for proteomic analysis is a difficult task mainly due to multiple preparation steps and sources for contaminations from other cellular compartments. The plasma membrane constitutes only about 5-20% of all the membranes in a plant cell, and therefore isolation of highly purified plasma membrane fraction is challenging. A frequently used method involves aqueous two-phase partitioning in polyethylene glycol and dextran, which yields plasma membrane vesicles with a purity of 95% 1. Sterol-rich membrane microdomains within the plasma membrane are insoluble upon treatment with cold nonionic detergents at alkaline pH. This detergent-resistant membrane fraction can be separated from the bulk plasma membrane by ultracentrifugation in a sucrose gradient 2. Subsequently, proteins can be extracted from the low density band of the sucrose gradient by methanol/chloroform precipitation. Extracted protein will then be trypsin digested, desalted and finally analyzed by LC-MS/MS. Our extraction protocol for sterol-rich microdomains is optimized for the preparation of clean detergent-resistant membrane fractions from Arabidopsis thaliana cell cultures.
We use full metabolic labeling of Arabidopsis thaliana suspension cell cultures with K15NO3 as the only nitrogen source for quantitative comparative proteomic studies following biological treatment of interest 3. By mixing equal ratios of labeled and unlabeled cell cultures for joint protein extraction the influence of preparation steps on final quantitative result is kept at a minimum. Also loss of material during extraction will affect both control and treatment samples in the same way, and therefore the ratio of light and heave peptide will remain constant. In the proposed method either labeled or unlabeled cell culture undergoes a biological treatment, while the other serves as control 4.

Metabolic Labeling and Membrane Fractionation for Comparative Proteomic Analysis of Arabidopsis thaliana Suspension Cell Cultures

Here we describe a robust method for the fractionation of plant plasma membranes into detergent resistant and detergent soluble membranes based on a mixture of unlabeled and in vivo fully 15N labeled Arabidopsis thaliana cell cultures. The procedure is applied for comparative proteomic studies to understand signaling processes.

代谢标记和膜分馏的比较蛋白质组学分析<em&gt;拟南芥</em&gt;悬浮细胞培养

Plasma membrane microdomains are features based on the physical properties of the lipid and sterol environment and have particular roles in signaling ...

A Seed Coat Bedding Assay to Genetically Explore In Vitro How the Endosperm Controls Seed Germination in Arabidopsis thaliana

The Arabidopsis endosperm consists of a single cell layer surrounding the mature embryo and playing an essential role to prevent the germination of dormant seeds or that of nondormant seeds irradiated by a far red (FR) light pulse. In order to further gain insight into the molecular genetic mechanisms underlying the germination repressive activity exerted by the endosperm, a &#34;seed coat bedding&#34; assay (SCBA) was devised. The SCBA is a dissection procedure physically separating seed coats and embryos from seeds, which allows monitoring the growth of embryos on an underlying layer of seed coats. Remarkably, the SCBA reconstitutes the germination repressive activities of the seed coat in the context of seed dormancy and FR-dependent control of seed germination. Since the SCBA allows the combinatorial use of dormant, nondormant and genetically modified seed coat and embryonic materials, the genetic pathways controlling germination and specifically operating in the endosperm and embryo can be dissected. Here we detail the procedure to assemble a SCBA.

A Seed Coat Bedding Assay to Genetically Explore In Vitro How the Endosperm Controls Seed Germination in Arabidopsis thaliana

We present the procedure to assemble a seed coat bedding assay (SCBA) from Arabidopsis thaliana seeds. The SCBA was shown to be a powerful tool to explore genetically and in vitro how the endosperm controls seed germination in dormant seeds and in response to light cues. The SCBA is in principle applicable under any situation where the endosperm is suspected to influence embryonic growth.

种皮床品检测到基因探索<em&gt;体外</em&gt;如何控制胚乳种子萌发的<em&gt;拟南芥</em

The Arabidopsis endosperm consists of a single cell layer surrounding the mature embryo and playing an essential role to prevent the germination of ...

An Efficient Method for Quantitative, Single-cell Analysis of Chromatin Modification and Nuclear Architecture in Whole-mount Ovules in Arabidopsis

In flowering plants, the somatic-to-reproductive cell fate transition is marked by the specification of spore mother cells (SMCs) in floral organs of the adult plant. The female SMC (megaspore mother cell, MMC) differentiates in the ovule primordium and undergoes meiosis. The selected haploid megaspore then undergoes mitosis to form the multicellular female gametophyte, which will give rise to the gametes, the egg cell and central cell, together with accessory cells. The limited accessibility of the MMC, meiocyte and female gametophyte inside the ovule is technically challenging for cytological and cytogenetic analyses at single cell level. Particularly, direct or indirect immunodetection of cellular or nuclear epitopes is impaired by poor penetration of the reagents inside the plant cell and single-cell imaging is demised by the lack of optical clarity in whole-mount tissues.
Thus, we developed an efficient method to analyze the nuclear organization and chromatin modification at high resolution of single cell in whole-mount embedded Arabidopsis ovules. It is based on dissection and embedding of fixed ovules in a thin layer of acrylamide gel on a microscopic slide. The embedded ovules are subjected to chemical and enzymatic treatments aiming at improving tissue clarity and permeability to the immunostaining reagents. Those treatments preserve cellular and chromatin organization, DNA and protein epitopes. The samples can be used for different downstream cytological analyses, including chromatin immunostaining, fluorescence in situ hybridization (FISH), and DNA staining for heterochromatin analysis. Confocal laser scanning microscopy (CLSM) imaging, with high resolution, followed by 3D reconstruction allows for quantitative measurements at single-cell resolution.

An Efficient Method for Quantitative, Single-cell Analysis of Chromatin Modification and Nuclear Architecture in Whole-mount Ovules in Arabidopsis

We provide here an efficient and reliable protocol for immunostaining, Fluorescence in&#160;situ Hybridization, DNA staining followed by quantitative, high-resolution imaging in whole-mount Arabidopsis thaliana ovules. This method was successfully used to analyze chromatin modifications and nuclear architecture.

定量，单细胞在全安装胚珠在染色质修饰和核体系结构分析的有效方法<em&gt;拟南芥</em

In flowering plants, the somatic-to-reproductive cell fate transition is marked by the specification of spore mother cells (SMCs) in floral organs of the ...

Measuring Spatial and Temporal Ca2+ Signals in Arabidopsis Plants

Developmental and environmental cues induce Ca2+ fluctuations in plant cells. Stimulus-specific spatial-temporal Ca2+ patterns are sensed by cellular Ca2+ binding proteins that initiate Ca2+ signaling cascades. However, we still know little about how stimulus specific Ca2+ signals are generated. The specificity of a Ca2+ signal may be attributed to the sophisticated regulation of the activities of Ca2+ channels and/or transporters in response to a given stimulus. To identify these cellular components and understand their functions, it is crucial to use systems that allow a sensitive and robust recording of Ca2+ signals at both the tissue and cellular levels. Genetically encoded Ca2+ indicators that are targeted to different cellular compartments have provided a platform for live cell confocal imaging of cellular Ca2+ signals. Here we describe instructions for the use of two Ca2+ detection systems: aequorin based FAS (film adhesive seedlings) luminescence Ca2+ imaging and case12 based live cell confocal fluorescence Ca2+ imaging. Luminescence imaging using the FAS system provides a simple, robust and sensitive detection of spatial and temporal Ca2+ signals at the tissue level, while live cell confocal imaging using Case12 provides simultaneous detection of cytosolic and nuclear Ca2+ signals at a high resolution.

Measuring Spatial and Temporal Ca2+ Signals in Arabidopsis Plants

Ca2+ signaling regulates diverse biological processes in plants. Here we present approaches for monitoring abiotic stress induced spatial and temporal Ca2+ signals in Arabidopsis cells and tissues using the genetically encoded Ca2+ indicators Aequorin or Case12.

测量时空的Ca<sup&gt; 2 +</sup&gt;在拟南芥信号

Developmental and environmental cues induce Ca2+ fluctuations in plant cells. Stimulus-specific spatial-temporal Ca2+ patterns are sensed by cellular Ca2+ ...

Isolation and Compositional Analysis of Plant Cuticle Lipid Polyester Monomers

Terrestrial plants produce extracellular aliphatic biopolyesters that modify cell walls of specific tissues. Epidermal cells synthesize cutin, a polyester of glycerol and modified fatty acids that constitutes the framework of the cuticle that covers aerial plant surfaces. Suberin is a related lipid polyester that is deposited on the cell walls of certain tissues, including the root endodermis and the periderm of tubers, tree bark and roots. These lipid polymers are highly variable in composition among plant species, and often differ among tissues within a single species. Here, we describe a detailed protocol to study the monomer composition of cutin in Arabidopsis thaliana leaves by sodium methoxide (NaOMe)-catalyzed depolymerisation, derivatization, and subsequent gas chromatography-mass spectrometry (GC/MS) analysis. This method can be used to investigate the monomers of insoluble polyesters isolated from whole delipidated plant tissues bearing either cutin or suberin. The method can by applied not only to characterize the composition of lipid polymers in species not previously analyzed, but also as an analytical tool in forward and reverse genetic approaches to assess candidate gene function.

Lipid polyesters constitute the structural components of two cell wall modifications, the plant cuticle and suberin-containing diffusion barriers. In this video, we describe a method to depolymerize cutin from whole delipidated leaves. The method can be applied to investigating mutants compromised in either cutin or suberin biosynthesis.

植物表皮脂质聚酯单体的分离及成分分析

Terrestrial plants produce extracellular aliphatic biopolyesters that modify cell walls of specific tissues. Epidermal cells synthesize cutin, a polyester ...

Lateral Root Inducible System in Arabidopsis and Maize

Lateral root development contributes significantly to the root system, and hence is crucial for plant growth. The study of lateral root initiation is however tedious, because it occurs only in a few cells inside the root and in an unpredictable manner. To circumvent this problem, a Lateral Root Inducible System (LRIS) has been developed. By treating seedlings consecutively with an auxin transport inhibitor and a synthetic auxin, highly controlled lateral root initiation occurs synchronously in the primary root, allowing abundant sampling of a desired developmental stage. The LRIS has first been developed for Arabidopsis thaliana, but can be applied to other plants as well. Accordingly, it has been adapted for use in maize (Zea mays). A detailed overview of the different steps of the LRIS in both plants is given. The combination of this system with comparative transcriptomics made it possible to identify functional homologs of Arabidopsis lateral root initiation genes in other species as illustrated here for the CYCLIN B1;1 (CYCB1;1) cell cycle gene in maize. Finally, the principles that need to be taken into account when an LRIS is developed for other plant species are discussed.

Lateral Root Inducible System in Arabidopsis and Maize

The Lateral Root Inducible System (LRIS) allows for synchronous induction of lateral roots and is presented for Arabidopsis thaliana and maize.

侧根诱导系统<em&gt;拟南芥</em&gt;和玉米

Lateral root development contributes significantly to the root system, and hence is crucial for plant growth. The study of lateral root initiation is ...

High Resolution Quantification of Crystalline Cellulose Accumulation in Arabidopsis Roots to Monitor Tissue-specific Cell Wall Modifications

Plant cells are surrounded by a cell wall, the composition of which determines their final size and shape. The cell wall is composed of a complex matrix containing polysaccharides that include cellulose microfibrils that form both crystalline structures and cellulose chains of amorphous organization. The orientation of the cellulose fibers and their concentrations dictate the mechanical properties of the cell. Several methods are used to determine the levels of crystalline cellulose, each bringing both advantages and limitations. Some can distinguish the proportion of crystalline regions within the total cellulose. However, they are limited to whole-organ analyses that are deficient in spatiotemporal information. Others relying on live imaging, are limited by the use of imprecise dyes. Here, we report a sensitive polarized light-based system for specific quantification of relative light retardance, representing crystalline cellulose accumulation in cross sections of Arabidopsis thaliana roots. In this method, the cellular resolution and anatomical data are maintained, enabling direct comparisons between the different tissues composing the growing root. This approach opens a new analytical dimension, shedding light on the link between cell wall composition, cellular behavior and whole-organ growth.

High Resolution Quantification of Crystalline Cellulose Accumulation in Arabidopsis Roots to Monitor Tissue-specific Cell Wall Modifications

Crystalline cellulose is an important constituent of the plant cell wall. However, its quantification at a cellular resolution is technically challenging. Here, we report the use of polarized light technology and root cross sections to obtain information of cell wall composition at a spatiotemporal resolution.

结晶纤维素积累高分辨率的量化<em&gt;拟南芥</em&gt;根监视特定组织细胞壁修改

Plant cells are surrounded by a cell wall, the composition of which determines their final size and shape. The cell wall is composed of a complex matrix ...

Rapid Analysis of Circadian Phenotypes in Arabidopsis Protoplasts Transfected with a Luminescent Clock Reporter

The plant circadian clock allows the anticipation of daily changes to the environment. This anticipation aids the responses to temporally predictable biotic and abiotic stress. Conversely, disruption of circadian timekeeping severely compromises plant health and reduces agricultural crop yields. It is therefore imperative that we understand the intricate regulation of circadian rhythms in plants, including the factors that affect motion of the transcriptional clockwork itself.
Testing circadian defects in the model plant Arabidopsis thaliana (Arabidopsis) traditionally involves crossing specific mutant lines to a line rhythmically expressing firefly luciferase from a circadian clock gene promoter. This approach is laborious, time-consuming, and could be fruitless if a mutant has no circadian phenotype. The methodology presented here allows a rapid initial assessment of circadian phenotypes. Protoplasts derived from mutant and wild-type Arabidopsis are isolated, transfected with a rhythmically expressed luminescent reporter, and imaged under constant light conditions for 5 days. Luminescent traces will directly reveal whether the free-running period of mutant plants is different from wild-type plants. The advantage of the method is that any Arabidopsis line can efficiently be screened, without the need for generating a stably transgenic luminescent clock marker line in that mutant background.

The circadian clock regulates about a third of the Arabidopsis transcriptome, but the percentage of genes that feed back into timekeeping remains unknown. Here we visualize a method to rapidly assess circadian phenotypes in any mutant line of Arabidopsis using luminescent imaging of a circadian reporter transiently expressed in protoplasts.

在拟南芥原生质体转染昼夜的表型有荧光时钟记者的快速分析

The plant circadian clock allows the anticipation of daily changes to the environment. This anticipation aids the responses to temporally predictable ...

Standardized Method for High-throughput Sterilization of Arabidopsis Seeds

Arabidopsis thaliana (Arabidopsis) seedlings often need to be grown on sterile media. This requires prior seed sterilization to prevent the growth of microbial contaminants present on the seed surface. Currently, Arabidopsis seeds are sterilized using two distinct sterilization techniques in conditions that differ slightly between labs and have not been standardized, often resulting in only partially effective sterilization or in excessive seed mortality. Most of these methods are also not easily scalable to a large number of seed lines of diverse genotypes. As technologies for high-throughput analysis of Arabidopsis continue to proliferate, standardized techniques for sterilizing large numbers of seeds of different genotypes are becoming essential for conducting these types of experiments. The response of a number of Arabidopsis lines to two different sterilization techniques was evaluated based on seed germination rate and the level of seed contamination with microbes and other pathogens. The treatments included different concentrations of sterilizing agents and times of exposure, combined to determine optimal conditions for Arabidopsis seed sterilization. Optimized protocols have been developed for two different sterilization methods: bleach (liquid-phase) and chlorine (Cl2) gas (vapor-phase), both resulting in high seed germination rates and minimal microbial contamination. The utility of these protocols was illustrated through the testing of both wild type and mutant seeds with a range of germination potentials. Our results show that seeds can be effectively sterilized using either method without excessive seed mortality, although detrimental effects of sterilization were observed for seeds with lower than optimal germination potential. In addition, an equation was developed to enable researchers to apply the standardized chlorine gas sterilization conditions to airtight containers of different sizes. The protocols described here allow easy, efficient, and inexpensive seed sterilization for a large number of Arabidopsis lines.

The objective of this study was to determine the effects of bleach and chlorine gas sterilization on seed germination of a range of Arabidopsis genotypes grown on sterile media. Optimized sterilization protocols have been developed to prevent the growth of microbial contaminants while providing satisfactory seed survival.

拟南芥种子高通量灭菌的标准化方法

Arabidopsis thaliana (Arabidopsis) seedlings often need to be grown on sterile media. This requires prior seed sterilization to prevent the growth of ...