我们感谢乔治·贾维斯，玛莎博克和贝特Hecox - 李，海洋生物实验室，他们在拍戏的帮助。

1.媒体的制备注意:使用盐度16.5个百分点（PSU）的一半稀释Brujewicz人造海水。其他人工海水也经常用于培养轮虫臂 25,26。 <ol><li>加454毫摩尔NaCl，26毫的MgCl 2，27毫硫酸镁 ，10毫米氯化钾和10mM的CaCl 2到4.5升蒸馏水（最终体积为5升）。另外，使用去离子水稀释代替蒸馏水。溶解所有其他盐后添加氯化钙 。 </li><li>准备0.48中号碳酸氢钠原液（200倍浓度）。将25ml添加到上述溶液中。的NaHCO 3的最终浓度为2.4毫摩尔。 </li><li>制备0.4M的溴化钠储备液（500X浓度）。加入10ml其添加到上述溶液中。溴化钠的最终浓度为0.8毫摩尔。补至5升蒸馏水。 </li><li>过滤用0.45μm的膜过滤器的溶液。在使用前用无菌水两次稀释（V / V）。 注意:可以使Brujewicz人工海水的2倍浓度作为原液。 </li></ol> 2.一般培养条件<ol><li>培养实验室饲养或在20和30℃之间的无菌100毫升烧杯野生捕获轮虫。较高的温度导致寿命较短，加速繁殖。使用25℃下的实验的方便性。轮虫密度或人工海水量是不是在这里一个大问题。 </li><li>文化饮食微藻在人工海水中11。见斯内尔等人 （2014年）的详细信息11。通常情况下，使用四爿tetrathele（〜2×10 5个细胞/ ml 27,28），T。 suecica（〜6×10 5个细胞/ ml 25,29），和微绿球藻 （〜7×10 6个细胞/ ml 30,31），由于饮食藻（种类，培养康迪特离子，生化成分）显著影响轮虫臂尾轮虫的存活时间，用同一地段微藻各实验组。 </li><li>喂养偶尔改变介质（ 如 ，喂，每2天，每周接种）保持在分批培养轮虫的股票群体。许多新生儿和成人轴承鸡蛋2-3个可以在轮虫是在最佳条件下进行观察。 注:另一种方式来获得实验轮虫是孵化休眠卵。从休眠卵孵出轮虫被认为是很好地同步，并且他们的寿命是不从来自amictic鸡蛋11孵出轮虫显著不同。然而，从休眠卵轮虫早于从amictic鸡蛋开始再现。因此，需要对它们的繁殖性状测量慎用。 </li></ol> 3.同步轮虫通过预培养<ol><li>选择从ST单轮虫玉珠人口和培养在2.1-2.3如上所述建立一个亚群将被用于实验。通常培养两周。 </li><li>收集来自亚群蛋承载轮虫（收集将用于实验的个体的双号）。培养它们作为一个单一的队列（密度:〜50个/毫升），在新鲜的介质下自由采食在2.1-2.3中描述的6孔培养板中。控制人口密度是重要的，因为条件培养基影响轮虫臂 32,33的生殖生理。 </li><li>转移从成人的第一个卵孵化到新制备培养基新生儿。重复此过程在2-3代。 </li><li>使用用于测量生存时间的特定时间段（ 例如 ，&lt;3小时）内画影线的新生儿。为了避免可能偏向于选择单一的个体，虽然很不可能的，用几个不知疲倦重复性检查侧亚群。 注:由于轮虫繁殖通常只无性这种情况下，确保无男性是整个实验过程中存在。男性比新生儿小，典型的移动比女性更快。混交雌体具有amictic女性在一定条件下29种不同的寿命。 </li></ol> 4.生存时间的测量<ol><li>在塑料板代替新生儿（通常24或48孔板，每孔含有1ml人工海水）。 </li><li>在24小时的时间间隔，如果在较高的温度（30℃以上）传送轮虫到新制备的培养基，或在12小时的时间间隔。记录的后代的数量和每一个人无论是死是活。记录轮虫死时电晕的纤毛运动完全停止。 注意:轮虫经常附着到孔的侧壁。水的轻柔吹打有助于找到他们。如果轮虫找不到或ArË小心被移液破坏，记录他们为"封杀"，而不是"死"。 </li><li>新生儿取出实验时，轮虫正在积极重现。新生儿快速增长，这是有时很难从实验轮虫区分。 </li></ol> 5.数据分析<ol><li>创建Kaplan-Meier生存曲线（ 图1和2）通过在Y轴和时间在X轴上标绘的累积存活率。这是存活数据的最常见的代表。使用的存活时间34统计比较的非参数数秩检验（也称为曼特尔-考克斯测试）。对数秩检验也被包括在其他标准统计软件包如JMP和R. 注:请不要使用学生t检验或后面的参数多重比较方差分析的分析，因为正态分布通常不是由生存数据35满足。此外，这些方法具DS不采取截尾的个人考虑。如果没有删数据曼 - 惠特尼U检验都可以使用。 </li></ol>

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L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+role+of+parental+age+effects+on+the+evolution+of+aging.">The role of parental age effects on the evolution of aging.</a> Evolution. 56 (5), 927-935 (2002).</li></ol>

The authors have nothing to disclose.

目前的协议描述了测量在臂轮虫的存活时间的方法。关键的步骤是轮虫条件几代同步。当实验轮虫以及同步的，一个典型的I型的生存曲线是用很少的早期死亡率观察到几个以前的研究报告18,24,37,38。相比较差同步轮虫的存活时间的标准偏差因此变得更小，从而导致高的统计力量。同步也有望增加存活时间测量的再现 - 因为母亲在最佳条件下培养时，当前协议抵消母体世代的可能的?...

轮虫是微观世界性浮游动物（&lt;1毫米）构成门轮虫1。它们具有约1,000的体细胞，以及一个特性轮状睫状装置构成的简单的身体计划称为电晕，其用于运动和进纸。大多数轮虫属于类Monogononta或玄武湖的轮虫，其中包含约1600和500种，分别为2。 Monogonont轮虫一般同时具有有性和无性繁殖阶段（周期性孤雌生殖），而蛭形轮虫繁殖通过强制性孤雌生殖3。因此，有可能获得基因完全相同轮虫个人，从而确保在实验高再现性。此外，它们具有其它几个优点模式生物，如短寿命，易于培养，基因组和转录组序列数据4-7的可用性，以及独特的系统位置远离一rthropods和线虫8。因此轮虫是有希望在生态毒理学无脊椎动物模型和老化研究9-12。 下暴露于环境压力或化学品的生存时间是在这些研究领域一个13-19经常测量参数。但是，衡量轮虫的存活时间的时候，因为很容易受到他们的母亲的环境条件是需要谨慎。也就是说，在monogonont 臂尾轮虫manjavacas，雌性后代从母亲年龄比那些年轻的妈妈寿命较短;然而，产妇热量限制（CR），部分抵消了先进的孕产妇20岁的有害影响。在B.轮虫 ，母亲CR提供后代长寿，饥饿状态下存活时间长，并与抗氧化酶21,22表达增强相关的高氧化应激性。产妇年龄效应也已在蛭形轮虫23观察到。因此，实验轮虫的条件应仔细的存活时间测量同步前几代。 在这里，我们提供了以下几代的培养条件同步的轮虫臂存活时间测量的协议。间歇禁食（IF），其中轮虫周期性馈送CR的变化，施加于揭示的同步的效果由于中频对长寿22,24众所周知的效果。

<table><tbody><tr><td>Sodium chloride</td><td>Wako</td><td>190-13921</td><td></td></tr><tr><td>Magnesium chloride</td><td>Wako</td><td>136-03995</td><td></td></tr><tr><td>Magnesium sulfate</td><td>Wako</td><td>131-00427</td><td></td></tr><tr><td>Potassium chloride</td><td>Wako</td><td>168-22111</td><td></td></tr><tr><td>Calcium chloride</td><td>Wako</td><td>035-00455</td><td></td></tr><tr><td>Sodium bicarbonate</td><td>Wako</td><td>199-05985</td><td></td></tr><tr><td>Sodium bromide</td><td>Wako</td><td>190-01515</td><td></td></tr><tr><td>Membrane filter (0.45 &amp;micro;m pore size)</td><td>Millipore</td><td>HAWP04700</td><td></td></tr><tr><td>Culture plate, 6-well, non-treated</td><td>Thomas Scientific</td><td>6902D01</td><td>Flat bottom</td></tr><tr><td>Culture plate, 48-well, non-treated</td><td>Thomas Scientific</td><td>6902D07</td><td>Flat bottom</td></tr><tr><td>Tetraselmis, Living</td><td>Carolina Biological Supply Company</td><td>152610</td><td></td></tr><tr><td>PRISM 6</td><td>GraphPad Software</td><td>Version 6.0d</td><td></td></tr></tbody></table>

measurement of survival time in brachionus rotifers: synchronization of maternal conditions

Rotifers are microscopic cosmopolitan zooplankton used as models in ecotoxicological and aging studies due to their several advantages such as short lifespan, ease of culture, and parthenogenesis that enables clonal culture. However, caution is required when measuring their survival time as it is affected by maternal age and maternal feeding conditions. Here we provide a protocol for powerful and reproducible measurement of the survival time in Brachionus rotifers following a careful synchronization of culture conditions over several generations. Empirically, poor synchronization results in early mortality and a gradual decrease in survival rate, thus resulting in weak statistical power. Indeed, under such conditions, calorie restriction (CR) failed to significantly extend the lifespan of B. plicatilis although CR-induced longevity has been demonstrated with well-synchronized rotifer samples in past and present studies. This protocol is probably useful for other invertebrate models, including the fruitfly Drosophila melanogaster and the nematode Caenorhabditis elegans, because maternal age effects have also been reported in these species.

图1显示了同步较差人群（出两个重复的）的代表生存曲线。在这个实验中，轮虫要么美联储日常[ 自由采食 （AL）组]或隔日（IF组）。中位生存期在美联和IF组13和18日，分别。虽然这是众所周知的，如果延伸轮虫的寿命，本实验未能检测到的AL和IF组的寿命之间存在统计学显著差异。根据经验，在早期死亡率和生存率下降逐渐同步不足的结果在这个...

Watch this Scientific Journal Video about Measurement of Survival Time in Brachionus Rotifers: Synchronization of Maternal Conditions at JoVE.com

Measurement of Survival Time in Brachionus Rotifers: Synchronization of Maternal Conditions

Rotifers are microscopic zooplankton used as models in ecotoxicological and aging studies. Here we provide a protocol for powerful and reproducible measurement of survival time in Brachionus rotifers. Synchronization of culture conditions over several generations is of particular importance because maternal condition affects life history of offspring.

生存时间的测量<em&gt;臂</em&gt;轮虫:产妇条件同步

Rotifers are microscopic cosmopolitan zooplankton used as models in ecotoxicological and aging studies due to their several advantages such as short ...

measurement-survival-time-brachionus-rotifers-synchronization

Research

JoVE Journal

Biology

Measurement of Survival Time in Brachionus Rotifers: Synchronization of Maternal Conditions

8.4K 次观看.  The University of Tokyo. Rotifers are microscopic zooplankton used as models in ecotoxicological and aging studies. Here we provide a protocol for powerful and reproducible measurement of survival time in Brachionus rotifers. Synchronization of culture conditions over several generations is of particular importance because maternal condition affects life history of offspring.

视频: Measurement of Survival Time in Brachionus Rotifers: Synchronization of Maternal Conditions

The Replica Set Method: A High-throughput Approach to Quantitatively Measure Caenorhabditis elegans Lifespan

The Replica Set method is an approach to quantitatively measure lifespan or survival of Caenorhabditis elegans nematodes in a high-throughput manner, thus allowing a single investigator to screen more treatments or conditions over the same amount of time without loss of data quality. The method requires common equipment found in most laboratories working with C. elegans and is thus simple to adopt. The approach centers on assaying independent samples of a population at each observation point, rather than a single sample over time as with traditional longitudinal methods. Scoring entails adding liquid to the wells of a multi-well plate, which stimulates C. elegans to move and facilitates quantifying changes in healthspan. Other major benefits of the Replica Set method include reduced exposure of agar surfaces to airborne contaminants (e.g. mold or fungus), minimal handling of animals, and robustness to sporadic mis-scoring (such as calling an animal as dead when it is still alive). To appropriately analyze and visualize the data from a Replica Set style experiment, a custom software tool was also developed. Current capabilities of the software include plotting of survival curves for both Replica Set and traditional (Kaplan-Meier) experiments, as well as statistical analysis for Replica Set. The protocols provided here describe the traditional experimental approach and the Replica Set method, as well as an overview of the corresponding data analysis.

The Replica Set Method: A High-throughput Approach to Quantitatively Measure Caenorhabditis elegans Lifespan

Here we describe the Replica Set method, an approach to quantitatively measure C. elegans lifespan/survival and healthspan in a high-throughput and robust manner, thus allowing screening of many conditions without sacrificing data quality. This protocol details the strategy and provides a software tool for analysis of Replica Set data.

复制集方法: 一种高通量方法定量测量秀丽线虫寿命

The Replica Set method is an approach to quantitatively measure lifespan or survival of Caenorhabditis elegans nematodes in a high-throughput manner, thus ...

科研

遗传学

Resurrection of Dormant Daphnia magna: Protocol and Applications

Long-term studies enable the identification of eco-evolutionary processes that occur over extended time periods. In addition, they provide key empirical data that may be used in predictive modelling to forecast evolutionary responses of natural ecosystems to future environmental changes. However, excluding a few exceptional cases, long-term studies are scarce because of logistic difficulties associated with accessing temporal samples. Temporal dynamics are frequently studied in the laboratory or in controlled mesocosm experiments with exceptional studies that reconstruct the evolution of natural populations in the wild.
Here, a standard operating procedure (SOP) is provided to revive or resurrect dormant Daphnia magna, a widespread zooplankton keystone species in aquatic ecosystems, to dramatically advance the state-of-the-art longitudinal data collection in natural systems. The field of Resurrection Ecology was defined in 1999 by Kerfoot and co-workers, even though the first attempts at hatching diapausing zooplankton eggs date back to the late 1980s. Since Kerfoot&#39;s seminal paper, the methodology of resurrecting zooplankton species has been increasingly frequently applied, though propagated among laboratories only via direct knowledge transfer. Here, an SOP is described that provides a step-by-step protocol on the practice of resurrecting dormant Daphnia magna eggs.
Two key studies are provided in which the fitness response of resurrected Daphnia magna populations to warming is measured, capitalizing on the ability to study historical and modern populations in the same settings. Finally, the application of next generation sequencing technologies to revived or still dormant stages is discussed. These technologies provide unprecedented power in dissecting the processes and mechanisms of evolution if applied to populations that have experienced changes in selection pressure over time.

Resurrection of Dormant Daphnia magna: Protocol and Applications

Long-term studies are essential to understanding the process of evolution and the mechanisms of adaptation. Generally, these studies require commitments beyond the life-time of researchers. Here, a powerful method is described that dramatically advances state-of-the-art data collection to generate longitudinal data in natural systems.

休眠蚤的复活: 协议和应用

Long-term studies enable the identification of eco-evolutionary processes that occur over extended time periods. In addition, they provide key empirical ...

环境科学

Measuring Replicative Life Span in the Budding Yeast

Aging is a degenerative process characterized by a progressive deterioration of cellular components and organelles resulting in mortality. The budding yeast Saccharomyces cerevisiae has been used extensively to study the biology of aging, and several determinants of yeast longevity have been shown to be conserved in multicellular eukaryotes, including worms, flies, and mice 1. Due to the lack of easily quantified age-associated phenotypes, aging in yeast has been assayed almost exclusively by measuring the life span of cells in different contexts, with two different life span paradigms in common usage 2. Chronological life span refers to the length of time that a mother cell can survive in a non-dividing, quiescence-like state, and is proposed to serve as a model for aging of post-mitotic cells in multicellular eukaryotes. Replicative life span, in contrast, refers the number of daughter cells produced by a mother cell prior to senescence, and is thought to provide a model of aging in mitotically active cells. Here we present a generalized protocol for measuring the replicative life span of budding yeast mother cells. The goal of the replicative life span assay is to determine how many times each mother cell buds. The mother and daughter cells can be easily differentiated by an experienced researcher using a standard light microscope (total magnification 160X), such as the Zeiss Axioscope 40 or another comparable model. Physical separation of daughter cells from mother cells is achieved using a manual micromanipulator equipped with a fiber-optic needle. Typical laboratory yeast strains produce 20-30 daughter cells per mother and one life span experiment requires 2-3 weeks.

In this article we present a general protocol for measuring the replicative life span of yeast mother cells.

在芽殖酵母中的自我复制寿命测量

Aging is a degenerative process characterized by a progressive deterioration of cellular components and organelles resulting in mortality. The budding ...

生物学

Surveying Low-Cost Methods to Measure Lifespan and Healthspan in Caenorhabditis elegans

The discovery and development of Caenorhabditis elegans as a model organism was influential in biology, particularly in the field of aging. Many historical and contemporary studies have identified thousands of lifespan-altering paradigms, including genetic mutations, transgenic gene expression, and hormesis, a beneficial, low-grade exposure to stress. With its many advantages, including a short lifespan, easy and low-cost maintenance, and fully sequenced genome with homology to almost two-thirds of all human genes, C. elegans has quickly been adopted as an outstanding model for stress and aging biology. Here, several standardized methods are surveyed for measuring lifespan and healthspan that can be easily adapted into almost any research environment, especially those with limited equipment and funds. The incredible utility of C. elegans is featured, highlighting the capacity to perform powerful genetic analyses in aging biology without the necessity of extensive infrastructure. Finally, the limitations of each analysis and alternative approaches are discussed for consideration.

Surveying Low-Cost Methods to Measure Lifespan and Healthspan in Caenorhabditis elegans

Caenorhabditis elegans serve as an excellent model system with robust and low-cost methods for surveying healthspan, lifespan, and resilience to stress.

调查低成本方法，以测量秀丽隐杆线虫的寿命和健康寿命

The discovery and development of Caenorhabditis elegans as a model organism was influential in biology, particularly in the field of aging. Many ...

Measuring Embryonic Viability and Brood Size in Caenorhabditis elegans

Caenorhabditis elegans is an excellent model organism for the study of meiosis, fertilization, and embryonic development. C. elegans exist as self-fertilizing hermaphrodites, which produce large broods of progeny-when males are present, they can produce even larger broods of cross progeny. Errors in meiosis, fertilization, and embryogenesis can be rapidly assessed as phenotypes of sterility, reduced fertility, or embryonic lethality. This article describes a method to determine embryonic viability and brood size in C. elegans. We demonstrate how to set up this assay by picking a worm onto an individual Modified Youngren's, Only Bacto-peptone (MYOB) plate, establish the appropriate timeframe to count viable progeny and non-viable embryos, and explain how to accurately count live worm specimens. This technique can be used to determine viability in self-fertilizing hermaphrodites as well as cross-fertilization by mating pairs. These relatively simple experiments are easily adoptable for new researchers, such as undergraduate students and first-year graduate students.

Measuring Embryonic Viability and Brood Size in Caenorhabditis elegans

Here, we present a general method to determine the embryonic viability and total number of embryos produced (brood) using the model organism C. elegans.

测量秀丽隐杆线虫的胚胎活力和育雏大小

Caenorhabditis elegans is an excellent model organism for the study of meiosis, fertilization, and embryonic development. C. elegans exist as ...

Observation and Quantification of Mating Behavior in the Pinewood Nematode, Bursaphelenchus xylophilus

A method for observing and quantifying the mating behavior of the pinewood nematode, Bursaphelenchus xylophilus, was established under a stereomicroscope. To improve the mating efficiency of B. Xylophilus and to increase the chances of mating observation, virgin adults were cultured and used for the investigation. Eggs were obtained by keeping the nematodes in water and allowing the females to lay eggs for 10 min. The second-stage juveniles (J2) were synchronized by incubating the eggs for 24 h at 25 &#176;C in the dark, and the early J4 were obtained by culturing the J2 with grey mold, Botrytis cinerea, for another 52 h. At this time point, most J4 nematodes could be clearly distinguished as being male or female using their genital morphology. The male and female J4 were collected and cultured separately in two different Petri dishes for 24 h to get virgin adult nematodes. A virgin male and a virgin female were paired in a drop of water in the well of a concave slide. The mating behavior was filmed with a video recorder under a stereomicroscope. The whole period of the mating process was 82.8 &#177;3.91 min (mean &#177;SE) and could be divided into 4 different phases: searching, contacting, copulating, and lingering. The mean minutes of duration were 21.8 &#177; 2.0, 28.0 &#177; 1.9, 25.8 &#177; 0.7 and 7.2 &#177; 0.5, respectively. Eleven sub-behaviors were described: cruising, approaching, encountering, touching, hooping, locating, attaching, ejaculating, separating, quiescence, and roaming. Interestingly, obvious intra-sexual competition was observed when one female was grouped with 3 males or one male with 3 females. This protocol is useful and valuable, not only in investigating the mating behavior of B. xylophilus, but also in acting as a reference for ethological studies of other nematodes.

Observation and Quantification of Mating Behavior in the Pinewood Nematode, Bursaphelenchus xylophilus

A protocol for investigating the mating behavior of the pinewood nematode, Bursaphelenchus xylophilus, is presented. Behavioral features of B. xylophilus are described in the mating process.

观察和交配行为的量化在我国松材线虫，<em&gt;松材线虫</em

A method for observing and quantifying the mating behavior of the pinewood nematode, Bursaphelenchus xylophilus, was established under a stereomicroscope. ...

Measurement of Oxygen Consumption Rates in Intact Caenorhabditis elegans

Optimal mitochondrial function is critical for healthy cellular activity, particularly in cells that have high energy demands like those in the nervous system and muscle. Consistent with this, mitochondrial dysfunction has been associated with a myriad of neurodegenerative diseases and aging in general. Caenorhabditis elegans have been a powerful model system for elucidating the many intricacies of mitochondrial function. Mitochondrial respiration is a strong indicator of mitochondrial function and recently developed respirometers offer a state-of-the-art platform to measure respiration in cells. In this protocol, we provide a technique to analyze live, intact C. elegans. This protocol spans a period of ~7 days and includes steps for (1) growing and synchronization of C. elegans, (2) preparation&#160;of compounds to be injected and hydration of probes, (3) drug loading and cartridge equilibration, (4) preparation of worm assay plate and assay run, and (5) post-experiment data analysis.

Measurement of Oxygen Consumption Rates in Intact Caenorhabditis elegans

Mitochondrial respiration is critical for organismal survival; therefore, oxygen consumption rate is an excellent indicator of mitochondrial health. In this protocol, we describe the use of a commercially available respirometer to measure basal and maximal oxygen consumption rates in live, intact, and freely-motile Caenorhabditis elegans.

线虫的耗氧率测定

Optimal mitochondrial function is critical for healthy cellular activity, particularly in cells that have high energy demands like those in the nervous ...

Standardizing a Non-Lethal Method for Characterizing the Reproductive Status and Larval Development of Freshwater Mussels (Bivalvia: Unionida)

Actively monitoring the timing, development, and reproductive patterns of endangered species is critical when managing for population recovery. Freshwater mussels are among the most imperiled organisms in the world, but information about early larval (glochidial) development and brooding periods is still lacking for many species. Previous studies have focused on the complex life history stage when female mussels are ready to parasitize host fish, but few studies have focused on the brooding period and timing of larval development. The protocol described here allows researchers to non-lethally evaluate the state of gravidity for female mussels. The results of this study show that this method does not affect a female mussel&rsquo;s ability to stay gravid or become gravid again after sampling has been performed. The advantage of this method may permit its use on federally threatened or endangered species or other populations of high conservation concern. This protocol can be adapted for use on both preserved or live individuals and was tested on a variety of mussel species. The database provided is a repository for a breadth of information on timing of reproductive habits and will facilitate future freshwater mussel research, conservation, and recovery efforts.

Standardizing a Non-Lethal Method for Characterizing the Reproductive Status and Larval Development of Freshwater Mussels Bivalvia: Unionida

Freshwater mussel conservation is dependent on monitoring reproductive patterns and processes of species. This study standardizes a non-lethal protocol for sampling gill contents, characterizing larval development, and providing a digital repository for data collected. This protocol-database package will be an important tool for mussel researchers in recovery of imperiled species.

标准化一种非致命方法，以描述淡水贝类的生殖状况和幼虫发育（比瓦尔维亚:联合达）

Actively monitoring the timing, development, and reproductive patterns of endangered species is critical when managing for population recovery. Freshwater ...

Measurements of Physiological Stress Responses in C. Elegans

Organisms are often exposed to fluctuating environments and changes in intracellular homeostasis, which can have detrimental effects on their proteome and physiology. Thus, organisms have evolved targeted and specific stress responses dedicated to repair damage and maintain homeostasis. These mechanisms include the unfolded protein response of the endoplasmic reticulum (UPRER), the unfolded protein response of the mitochondria (UPRMT), the heat shock response (HSR), and the oxidative stress response (OxSR). The protocols presented here describe methods to detect and characterize the activation of these pathways and their physiological consequences in the nematode, C. elegans. First, the use of pathway-specific fluorescent transcriptional reporters is described for rapid cellular characterization, drug screening, or large-scale genetic screening (e.g., RNAi or mutant libraries). In addition, complementary, robust physiological assays are described, which can be used to directly assess sensitivity of animals to specific stressors, serving as functional validation of the transcriptional reporters. Together, these methods allow for rapid characterization of the cellular and physiological effects of internal and external proteotoxic perturbations.

Measurements of Physiological Stress Responses in C. Elegans

Here, we characterize cellular proteotoxic stress responses in the nematode C. elegans by measuring the activation of fluorescent transcriptional reporters and assaying sensitivity to physiological stress.

C. Elegans生理应激反应的测量

Organisms are often exposed to fluctuating environments and changes in intracellular homeostasis, which can have detrimental effects on their proteome and ...

Nematode Synchronization: A Method to Obtain Populations of Worms in Identical Stages of Development

Source: Sarasija, S. and Norman, K. R. <a href="https://www.jove.com/video/59277/measurement-oxygen-consumption-rates-intact-caenorhabditis">Measurement of Oxygen Consumption Rates in Intact&#160;Caenorhabditis elegans</a>.&#160;J. Vis. Exp. (2019).
In this video, we show a method of producing a developmentally synchronized population of sterile adult C. elegans. The example protocol synchronizes worms to study oxygen consumption rates in live animals.

线虫同步:一种获取处于相同发育阶段的蠕虫种群的方法

Source: Sarasija, S. and Norman, K. R. Measurement of Oxygen Consumption Rates in Intact&#160;Caenorhabditis elegans.&#160;J. Vis. Exp. (2019).
In this ...

生存时间的测量

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