This work was supported by grants from the Natural Sciences and Engineering Research Council (NSERC) of Canada and The Canada Foundation for Innovation. Thanks to Dr Paul Mains (University of Calgary, Calgary, Canada) for let-502(sb118ts) strain. Some of the strains were provided by the Caenorhabditis Genetics Center, which is funded by NIH Office of Research Infrastructure Programs (P40 OD010440).

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The authors declare that they have no competing financial interests.

يصف هذا البروتوكول مقاييس جديدة للتميز في وقت مبكر ومراحل متأخرة من استطالة الجنينية. في الباب 1، الخطوة الحاسمة هي احتمال وجود البكتيريا على لوحة. وأرفقت الأجنة بإحكام بين لوحة وساترة خلال الحصول على الصور. ختم الشريحة هو مطلوب ?...

منذ ما يقرب من 50 عاما الديدان الخيطية انواع معينة ايليجانس ضعت نفسها كنموذج قوية لدراسة المسائل الهامة في عملية التنمية، بيولوجيا الأعصاب، والتطور، والتفاعلات المضيف الممرض، الخ. 1 إن قوة هذا النموذج في دراسة التطور تكمن في: دورة حياة قصيرة من 3 أيام؛ السهولة التي هذه الحيوانات يمكن تعديلها وراثيا. شفافيتها التي تمكن من مراقبة النزوح الخلية ومورفولوجيا في الحيوانات الحية وتطورها التي هي في معظمها خارج الرحم. مراحل تطور من الديدان الخيطية وتشمل مرحلة التطور الجنيني وأربع مراحل اليرقات (L1 إلى L4)، تليها مرحلة البلوغ. أثناء التطور الجنيني، ولفت البشرة التشكل اهتماما كبيرا لقدرته على تمكين فهم أفضل لكيفية الظهارية تهاجر الخلايا كمجموعة، كيف تعيد تنظيم تقاطعات وتعديل التشكل الفردي وكذلك تحديد المواقع النسبية في غضون ظهارة الوظيفية.ينقسم التشكل البشرة إلى أربع مراحل: إقحام الظهري التي تتمثل في إعادة تنظيم خلايا البشرة الظهرية، ويشار إلى اللحمة. الضميمة بطني، تتمثل في هجرة خلايا الطبقة الجلدية البطنية نحو خط الوسط البطني وبالتالي يغلف الجنين في أحادي الطبقة الخلايا الظهارية. المبكرة والمتأخرة استطالة تحويل الجنين على شكل حبة الفول إلى يرقات الدودي. بعد التشكل، فتحة الجنين وL1 اليرقات تبدأ التغذية باستخدام بكتيريا المتاحة في بيئتهم المباشرة. وبالتالي استطالة الجنينية هي مرحلة متأخرة من التطور الجنيني. وهو يتألف من تمديد الجنين على طول محورها الطولي والحد من قطرها عرضية. وهذا ينطوي على تعديل الهائل في شكل خلايا الطبقة الجلدية. ينقسم استطالة إلى وقت مبكر، ومرحلة متأخرة. تبدأ المرحلة الأولى في مرحلة فاصلة وتنتهي عندما تبدأ عضلات الجسم الجدار التعاقد في مرحلة 1.75 أضعاف في ثILD من نوع (وزن) الأجنة - الموافق الأجنة التي هي 1.75 أضعاف في طول مقارنة الأجنة غير ممدود. هي التي تحرك العمليات Morphogenic التي تحدث في تلك المرحلة بشكل رئيسي من قبل انكماش حزم الخيطية الأكتين (FBS) الواقعة في القطب القمي من خلايا الطبقة الجلدية التي تدفع استطالة على طول محور انتيرو الخلفي للجنين 2. انكماش FBS هو سيطرة الفسفرة من سلاسل الميوسين الضوء من قبل ثلاثة تحركات LET-502 / ROCK، MRCK-1 وPAK-1 5. مرحلة متأخرة من استطالة، يبدأ عندما تصبح عضلات الجسم الجدار الوظيفية وتبدأ التعاقد. أنها تنطوي على mechanotransduction إشارات من عضلات الجسم الجدار إلى الخلايا الظهرية والطبقة الجلدية البطنية وينتهي عندما يفقس الحيوانات 3. تتميز العيوب استطالة عموما نسبة الحيوانات الموت كما الأجنة (الفتك الجنينية، التطريز) وتلك القبض على تنميتها كما L1 اليرقات (اليرقات النمط الظاهري القبض، الوقفأ) ويكون أقصر بكثير من وزن. تحديد مرحلة الاعتقال التنموي يتطلب الملاحظة المجهرية للأجنة ميتة والقبض على يرقات 3-6. وقد تبين مؤخرا أن العديد من الجينات، مثل Cdc42 / منظم راك والمستجيب بيكسل-1 وباك-1، مراقبة العمليات morphogenic خلال كلا المبكرة والمتأخرة استطالة 3،7. نحن كما أظهرت مؤخرا أن عمليات morphogenic تختلف على طول المحور انتيرو الخلفي من الأجنة أثناء استطالة في وقت مبكر 3 7. هذه النتائج دافعا لتطوير مقاييس جديدة تستهدف على وجه التحديد مراحل استطالة مبكرة أو متأخرة والمقاييس الأخرى تمكين توصيف مورفولوجية الأجنة على طول محور انتيرو الخلفي أثناء استطالة في وقت مبكر. تتكون هذه الطرق المبتكرة في قياس طول الأجنة في بداية ونهاية استطالة المبكر، وكذلك عرض على انهوقد وضعت الإعلانات وذيول 7 بروتوكولين أيضا إلى قياس طول اليرقات حديثة الفقس، متزامنة في مرحلة L1 7. قشر البيض من الأجنة حمايتهم من التعرض للمعاملة هيبوكلوريت قلوية بينما حلت اليرقات والبالغين والبكتيريا الموجودة في وسائل الإعلام الثقافة عن طريق العلاج. ثم يتم استخدام هذا العلاج لتنقية الأجنة من السكان غير متزامنة تحتوي على معظم البالغين تغذية جيدة-8. يستخدم تقييد الغذاء لمزامنة اليرقات حديثة الفقس. قياس طول هذه اليرقات ثم يتم استخدامها للكشف عن العيوب استطالة. ويفضل هذا القياس على قياس اليرقات القبض على لوحات ثقافة لأن اليرقات التي تفقس من غير كامل الأجنة ممدود يمكن استرداد إلى &quot;الطول العادي&quot; عند تغذية ولكن ستحافظ على انخفاض حجمها عندما ألقي القبض عليه في حالة عدم وجود الطعام. هنا، نقدم بروتوكولات وإجراءات تفصيلية تمكن من قياس جنيهngth من التمطيط الأجنة وكذلك عرض الرأس والذيل باستخدام الوقت الفاصل بين مدينة دبي للإنترنت المجهري وتحليل الصور (بروتوكول 1). ونحن نقدم أيضا بروتوكولات وإجراءات تفصيلية لقياس طول اليرقات متزامنة باستخدام تحليل الصور (بروتوكول 2) والانسياب الخلوي (بروتوكول 3).

<table><tbody><tr><td>Agar&amp;nbsp;</td><td>BioShop</td><td>AGR001.500</td><td></td></tr><tr><td>Agarose</td><td>Bioshop</td><td>AGA001.500</td><td></td></tr><tr><td>CaCl&lt;sub&gt;2&lt;/sub&gt; (Calcium Chloride)</td><td>Bio Basic Inc.</td><td>CT1330</td><td></td></tr><tr><td>Cholesterol</td><td>Sigma-aldrich</td><td>C8667</td><td></td></tr><tr><td>Cleaning solution&amp;nbsp;</td><td>union Biometrica</td><td>300-5072-000</td><td></td></tr><tr><td>Glass coverslips</td><td>Fisherbrand</td><td>12-542B</td><td></td></tr><tr><td>Glass slides</td><td>Fisherbrand</td><td>12-552-3</td><td></td></tr><tr><td>High fluorescent control particles</td><td>union Biometrica</td><td>310-5071-001</td><td></td></tr><tr><td>K&lt;sub&gt;2&lt;/sub&gt;HPO&lt;sub&gt;4&lt;/sub&gt; (potassium phosphate, dibasic)</td><td>Bio Basic Inc.</td><td>PB0447</td><td></td></tr><tr><td>K&lt;sub&gt;2&lt;/sub&gt;HPO&lt;sub&gt;4&lt;/sub&gt; (potassium phosphate, monobasic)</td><td>Bio Basic Inc.</td><td>PB0445</td><td></td></tr><tr><td>MgSO&lt;sub&gt;4&lt;/sub&gt; (magnesium sulfate)</td><td>Sigma-aldrich</td><td>230391</td><td></td></tr><tr><td>Na&lt;sub&gt;2&lt;/sub&gt;HPO&lt;sub&gt;4&lt;/sub&gt;( sodium phosphate, dibasic)</td><td>Bio Basic Inc.</td><td>SDB0487</td><td></td></tr><tr><td>NaCl (sodium chloride)</td><td>Bio Basic Inc.</td><td>DB0483</td><td></td></tr><tr><td>Pebeo Drawing Gum 45&amp;nbsp;ml</td><td>p&amp;eacute;b&amp;eacute;o</td><td>PDG033000</td><td>any art/craft store</td></tr><tr><td>Peptone</td><td>BioShop</td><td>PEP403.500</td><td></td></tr><tr><td>Sheath buffer</td><td>union Biometrica</td><td>300-5070-100</td><td></td></tr><tr><td>COPAS Biosort</td><td>union Biometrica</td><td></td><td></td></tr></tbody></table>

novel metrics to characterize embryonic elongation of the nematode caenorhabditis elegans

Dissecting the signaling pathways that control the alteration of morphogenic processes during embryonic development requires robust and sensitive metrics. Embryonic elongation of the nematode Caenorhabditis elegans is a late developmental stage consisting of the elongation of the embryo along its longitudinal axis. This developmental stage is controlled by intercellular communication between hypodermal cells and underlying body-wall muscles. These signaling mechanisms control the morphology of hypodermal cells by remodeling the cytoskeleton and the cell-cell junctions. Measurement of embryonic lethality and developmental arrest at larval stages as well as alteration of cytoskeleton and cell-cell adhesion structures in hypodermal and muscle cells are classical phenotypes that have been used for more than 25 years to dissect these signaling pathways. Recent studies required the development of novel metrics specifically targeting either early or late elongation and characterizing morphogenic defects along the antero-posterior axis of the embryo. Here, we provide detailed protocols enabling the accurate measurement of the length and the width of the elongating embryos as well as the length of synchronized larvae. These methods constitute useful tools to identify genes controlling elongation, to assess whether these genes control both early and late phases of this stage and are required evenly along the antero-posterior axis of the embryo.

هولست Tail- ورئيس / الذيل عرض نسبة هي القياسات قوية. وقد تم استخدام البروتو?...

Watch this Scientific Journal Video about Novel Metrics to Characterize Embryonic Elongation of the Nematode Caenorhabditis elegans at JoVE.com

Novel Metrics to Characterize Embryonic Elongation of the Nematode Caenorhabditis elegans

رواية مقاييس لوصف الجنينية الاستطالة للنيماتودا<em&gt; انواع معينة ايليجانس</em

Here we detail protocols specifically designed to monitor morphogenic defects that occur during early and late phases of embryonic elongation of the nematode Caenorhabditis elegans. Ultimately, these protocols are designed to identify genes that regulate these phases and to characterize their differential requirements along the antero-posterior axis of the embryo.

Dissecting the signaling pathways that control the alteration of morphogenic processes during embryonic development requires robust and sensitive metrics. ...

novel-metrics-to-characterize-embryonic-elongation-nematode

Research

JoVE Journal

Neuroscience

Novel Metrics to Characterize Embryonic Elongation of the Nematode Caenorhabditis elegans

6.0K Views.  Université du Québec à Montréal. Here we detail protocols specifically designed to monitor morphogenic defects that occur during early and late phases of embryonic elongation of the nematode Caenorhabditis elegans. Ultimately, these protocols are designed to identify genes that regulate these phases and to characterize their differential requirements along the antero-posterior axis of the embryo. 

Video: Novel Metrics to Characterize Embryonic Elongation of the Nematode Caenorhabditis elegans

C. elegans Tracking and Behavioral Measurement

We have developed instrumentation, image processing, and data analysis techniques to quantify the locomotory behavior of C. elegans as it crawls on the surface of an agar plate. For the study of the genetic, biochemical, and neuronal basis of behavior, C. elegans is an ideal organism because it is genetically tractable, amenable to microscopy, and shows a number of complex behaviors, including taxis, learning, and social interaction1,2. Behavioral analysis based on tracking the movements of worms as they crawl on agar plates have been particularly useful in the study of sensory behavior3, locomotion4, and general mutational phenotyping5. Our system works by moving the camera and illumination system as the worms crawls on a stationary agar plate, which ensures no mechanical stimulus is transmitted to the worm. Our tracking system is easy to use and includes a semi-automatic calibration feature. A challenge of all video tracking systems is that it generates an enormous amount of data that is intrinsically high dimensional. Our image processing and data analysis programs deal with this challenge by reducing the worms shape into a set of independent components, which comprehensively reconstruct the worms behavior as a function of only 3-4 dimensions6,7. As an example of the process we show that the worm enters and exits its reversal state in a phase specific manner.

C. elegans Tracking and Behavioral Measurement

We have developed a video-rate tracking microscope system that can record and quantify C. elegans behavior at high resolution and high speeds. We have also developed computational methods to reduce the dimensionality of the worm images to a fundamental set of measurements that completely describe the shape of the worm.

C. ايليجانس تتبع وقياس السلوكية

We have developed instrumentation, image processing, and data analysis techniques to quantify the locomotory behavior of C. elegans as it crawls on the ...

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.

قياس الصلاحية الجنينية وحجم الحضنة في Caenorhabditis elegans

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

Genetics

Isotropic Light-Sheet Microscopy and Automated Cell Lineage Analyses to Catalogue Caenorhabditis elegans Embryogenesis with Subcellular Resolution

Caenorhabditis elegans (C. elegans) stands out as the only organism in which the challenge of understanding the cellular origins of an entire nervous system can be observed, with single cell resolution, in vivo. Here, we present an integrated protocol for the examination of neurodevelopment in C. elegans embryos. Our protocol combines imaging, lineaging and neuroanatomical tracing of single cells in developing embryos. We achieve long-term, four-dimensional (4D) imaging of living C. elegans&#160;embryos with nearly isotropic spatial resolution through the use of Dual-view Inverted Selective Plane Illumination Microscopy (diSPIM). Nuclei and neuronal structures in the nematode embryos are imaged and isotropically fused to yield images with resolution of ~330 nm in all three dimensions. These minute-by-minute high-resolution 4D data sets are then analyzed to correlate definitive cell-lineage identities with gene expression and morphological dynamics at single-cell and subcellular levels of detail. Our protocol is structured to enable modular implementation of each of the described steps and enhance studies on embryogenesis, gene expression, or neurodevelopment.

Here, we present a combinatorial approach using high-resolution microscopy, computational tools, and single-cell labeling in living C. elegans embryos to understand single cell dynamics during neurodevelopment.

المجهر الضوئي ورقه الخفيفة والمؤتمتة الخلايا النسب تحليلات لكتالوج Caenorhabditis الاجنه الجنينية مع القرار تحت الخلوية

Caenorhabditis elegans (C. elegans) stands out as the only organism in which the challenge of understanding the cellular origins of an entire nervous ...

Developmental Biology

Measuring Sperm Guidance and Motility within the Caenorhabditis elegans Hermaphrodite Reproductive Tract

Successful fertilization is fundamental to sexual reproduction, yet little is known about the mechanisms that guide sperm to oocytes within the female reproductive tract. While in vitro studies suggest that sperm of internally fertilizing animals can respond to various cues from their surroundings, the inability to visualize their behavior inside the female reproductive tract creates a challenge for understanding sperm migration and mobility in its native environment. Here, we describe a method using C. elegans that overcomes this limitation and takes advantage of their transparent epidermis. C. elegans males stained with a mitochondrial&#160; dye are mated with adult hermaphrodites, which act as modified females, and deposit fluorescently labeled sperm into the hermaphrodite uterus. The migration and motility of the labeled sperm can then be directly tracked using an epi-fluorescence microscope in a live hermaphrodite. In wild-type animals, approximately 90% of the labeled sperm crawl through the uterus and reach the fertilization site, or spermatheca. Images of the uterus can be taken 1 h after mating to assess the distribution of the sperm within the uterus and the percentage of sperm that have reached the spermatheca. Alternatively, time-lapse images can be taken immediately after mating to assess sperm speed, directional velocity and reversal frequency. This method can be combined with other genetic and molecular tools available for the C.elegans to identify novel genetic and molecular mechanisms that are important in regulating sperm guidance and motility within the female reproductive tract.

Measuring Sperm Guidance and Motility within the Caenorhabditis elegans Hermaphrodite Reproductive Tract

Sperm must successfully navigate through the oviduct to fertilize an oocyte. Here, we describe an assay for measuring sperm migration within the C. elegans hermaphrodite uterus. This assay can provide quantitative data on sperm distribution within the uterus after mating, as well as on speed, directional velocity, and reversal frequency.

قياس الإرشاد المنوي والحركية داخل الجهاز التناسلي المخنث

Successful fertilization is fundamental to sexual reproduction, yet little is known about the mechanisms that guide sperm to oocytes within the female ...

A Semi-high-throughput Imaging Method and Data Visualization Toolkit to Analyze C. elegans Embryonic Development

C. elegans is the premier system for the systematic analysis of cell fate specification and morphogenetic events during embryonic development. One challenge is that embryogenesis dynamically unfolds over a period of about 13 h; this half day-long timescale has constrained the scope of experiments by limiting the number of embryos that can be imaged. Here, we describe a semi-high-throughput protocol that allows for the simultaneous 3D time-lapse imaging of development in 80&#8211;100 embryos at moderate time resolution, from up to 14 different conditions, in a single overnight run. The protocol is straightforward and can be implemented by any laboratory with access to a microscope with point visiting capacity. The utility of this protocol is demonstrated by using it to image two custom-built strains expressing fluorescent markers optimized to visualize key aspects of germ-layer specification and morphogenesis. To analyze the data, a custom program that crops individual embryos out of a broader field of view in all channels, z-steps, and timepoints and saves the sequences for each embryo into a separate tiff stack was built. The program, which includes a user-friendly graphical user interface (GUI), streamlines data processing by isolating, pre-processing, and uniformly orienting individual embryos in preparation for visualization or automated analysis. Also supplied is an ImageJ macro that compiles individual embryo data into a multi-panel file that displays maximum intensity fluorescence projection and brightfield images for each embryo at each time point. The protocols and tools described herein were validated by using them to characterize embryonic development following knock-down of 40 previously described developmental genes; this analysis visualized previously annotated developmental phenotypes and revealed new ones. In summary, this work details a semi-high-throughput imaging method coupled with a cropping program and ImageJ visualization tool that, when combined with strains expressing informative fluorescent markers, greatly accelerates experiments to analyze embryonic development.

A Semi-high-throughput Imaging Method and Data Visualization Toolkit to Analyze C. elegans Embryonic Development

This work describes a semi-high-throughput protocol that allows simultaneous 3D time-lapse imaging of embryogenesis in 80&#8211;100 C. elegans embryos in a single overnight run. Additionally, image processing and visualization tools are included to streamline data analysis. The combination of these methods with custom reporter strains enables detailed monitoring of embryogenesis.

طريقه التصوير شبه عاليه الانتاجيه ومجموعه أدوات التصور البيانات لتحليل التنمية الجنينية c. اليجس

C. elegans is the premier system for the systematic analysis of cell fate specification and morphogenetic events during embryonic development. One ...

4D Microscopy: Unraveling Caenorhabditis elegans Embryonic Development Using Nomarski Microscopy

4D microscopy is an invaluable tool for unraveling the embryonic developmental process in different animals. Over the last decades, Caenorhabditis elegans has emerged as one of the best models for studying development. From an optical point of view, its size and transparent body make this nematode an ideal specimen for DIC (Differential Interference Contrast or Nomarski) microscopy. This article illustrates a protocol for growing C. elegans nematodes, preparing and mounting their embryos, performing 4D microscopy and cell lineage tracing. The method is based on multifocal time-lapse records of Nomarski images and analysis with specific software. This technique reveals embryonic developmental dynamics at the cellular level. Any embryonic defect in mutants, such as problems in spindle orientation, cell migration, apoptosis or cell fate specification, can be efficiently detected and scored. Virtually every single cell of the embryo can be followed up to the moment the embryo begins to move. Tracing the complete cell lineage of a C. elegans embryo by 4D DIC microscopy is laborious, but the use of specific software greatly facilitates this task. In addition, this technique is easy to implement in the lab. 4D microscopy is a versatile tool and opens the possibility of performing an unparalleled analysis of embryonic development.

4D Microscopy: Unraveling Caenorhabditis elegans Embryonic Development Using Nomarski Microscopy

Here, we present a protocol for preparing and mounting Caenorhabditis elegans embryos, recording development under a 4D microscope and tracing cell lineage.

4D المجهري: كشف Caenorhabditis elegans التطور الجنيني باستخدام المجهر نومارسكي

4D microscopy is an invaluable tool for unraveling the embryonic developmental process in different animals. Over the last decades, Caenorhabditis elegans ...

Imaging C. elegans Embryos using an Epifluorescent Microscope and Open Source Software

Cellular processes, such as chromosome assembly, segregation and cytokinesis,are inherently dynamic. Time-lapse imaging of living cells, using fluorescent-labeled reporter proteins or differential interference contrast (DIC) microscopy, allows for the examination of the temporal progression of these dynamic events which is otherwise inferred from analysis of fixed samples1,2. Moreover, the study of the developmental regulations of cellular processes necessitates conducting time-lapse experiments on an intact organism during development. The Caenorhabiditis elegans embryo is light-transparent and has a rapid, invariant developmental program with a known cell lineage3, thus providing an ideal experiment model for studying questions in cell biology4,5and development6-9. C. elegans is amendable to genetic manipulation by forward genetics (based on random mutagenesis10,11) and reverse genetics to target specific genes (based on RNAi-mediated interference and targeted mutagenesis12-15). In addition, transgenic animals can be readily created to express fluorescently tagged proteins or reporters16,17. These traits combine to make it easy to identify the genetic pathways regulating fundamental cellular and developmental processes in vivo18-21. In this protocol we present methods for live imaging of C. elegans embryos using DIC optics or GFP fluorescence on a compound epifluorescent microscope. We demonstrate the ease with which readily available microscopes, typically used for fixed sample imaging, can also be applied for time-lapse analysis using open-source software to automate the imaging process.

Imaging C. elegans Embryos using an Epifluorescent Microscope and Open Source Software

The C. elegans embryo is a powerful system for studying cell biology and development. We present a protocol for live imaging of C. elegans embryos utilizing DIC optics or fluorescence using readily available epifluorescent microscopes and open-source software.

التصوير C. ايليجانس الأجنة باستخدام مجهر Epifluorescent وبرمجيات المصدر المفتوح

Cellular processes, such as chromosome assembly, segregation and cytokinesis,are inherently dynamic. Time-lapse imaging of living cells, using ...

Biology

Basic Caenorhabditis elegans Methods: Synchronization and Observation

Research into the molecular and developmental biology of the nematode Caenorhabditis elegans was begun in the early seventies by Sydney Brenner and it has since been used extensively as a model organism 1. C. elegans possesses key attributes such as simplicity, transparency and short life cycle that have made it a suitable experimental system for fundamental biological studies for many years 2. Discoveries in this nematode have broad implications because many cellular and molecular processes that control animal development are evolutionary conserved 3.
C. elegans life cycle goes through an embryonic stage and four larval stages before animals reach adulthood. Development can take 2 to 4 days depending on the temperature. In each of the stages several characteristic traits can be observed. The knowledge of its complete cell lineage 4,5 together with the deep annotation of its genome turn this nematode into a great model in fields as diverse as the neurobiology 6, aging 7,8, stem cell biology 9 and germ line biology 10. 
An additional feature that makes C. elegans an attractive model to work with is the possibility of obtaining populations of worms synchronized at a specific stage through a relatively easy protocol. The ease of maintaining and propagating this nematode added to the possibility of synchronization provide a powerful tool to obtain large amounts of worms, which can be used for a wide variety of small or high-throughput experiments such as RNAi screens, microarrays, massive sequencing, immunoblot or in situ hybridization, among others. 
Because of its transparency, C. elegans structures can be distinguished under the microscope using Differential Interference Contrast microscopy, also known as Nomarski microscopy. The use of a fluorescent DNA binder, DAPI (4',6-diamidino-2-phenylindole), for instance, can lead to the specific identification and localization of individual cells, as well as subcellular structures/defects associated to them.

Basic Caenorhabditis elegans Methods: Synchronization and Observation

The easiness of maintaining and propagating the nematode C. elegans make it a nice model organism to work with. The possibility of synchronizing worms allows the work with a significant amount of subjects at the same developmental stage, what facilitates the study of one particular process in many animals.

الأساسية<em&gt; Caenorhabditis ايليجانس</em&gt; طرق: التزامن والمراقبة

Research into the molecular and developmental biology of the nematode Caenorhabditis elegans was begun in the early seventies by Sydney Brenner and it has ...

Tracking and Quantifying Developmental Processes in C. elegans Using Open-source Tools

Quantitatively capturing developmental processes is crucial to derive mechanistic models and key to identify and describe mutant phenotypes. Here protocols are presented for preparing embryos and adult C. elegans animals for short- and long-term time-lapse microscopy and methods for tracking and quantification of developmental processes. The methods presented are all based on C. elegans strains available from the Caenorhabditis Genetics Center and on open-source software that can be easily implemented in any laboratory independently of the microscopy system used. A reconstruction of a 3D cell-shape model using the modelling software IMOD, manual tracking of fluorescently-labeled subcellular structures using the multi-purpose image analysis program Endrov, and an analysis of cortical contractile flow using PIVlab (Time-Resolved Digital Particle Image Velocimetry Tool for MATLAB) are shown. It is discussed how these methods can also be deployed to quantitatively capture other developmental processes in different models, e.g., cell tracking and lineage tracing, tracking of vesicle flow.

Tracking and Quantifying Developmental Processes in C. elegans Using Open-source Tools

Here it is shown how to track and quantify developmental processes in C. elegans. The methods presented are based on open-source tools that can be easily implemented. It is demonstrated how to reconstruct 3D cell-shape models, how to manually track subcellular structures, and how to analyze cortical contractile flow.

تتبع وقياس العمليات التنموية في<em&gt; C. ايليجانس</em&gt; استخدام أدوات المصدر المفتوح

Quantitatively capturing developmental processes is crucial to derive mechanistic models and key to identify and describe mutant phenotypes. Here ...

Lifespan Analysis: Measuring C. elegans Longevity

Source: Cornwell, A. B., et al. <a href="https://www.jove.com/video/57819/the-replica-set-method-high-throughput-approach-to-quantitatively">The Replica Set Method: A High-throughput Approach to Quantitatively Measure&#160;Caenorhabditis elegans&#160;Lifespan</a>.&#160;J. Vis. Exp.&#160; (2018).
This video describes a traditional, plate-based method of measuring the lifespan of C. elegans. The example protocol measures the lifespan of worms treated with RNAi.

رواية مقاييس لوصف الجنينية الاستطالة للنيماتودا

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