We gratefully thank the DFG for financial support (HO 1779/21-1) as well as Katrin Kumke and Dr. Veit Schubert (IPK, Gatersleben) for technical advice.

1. إعداد كروموسوم <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> إنبات البذور والتثبيت من النصائح الجذر <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> تنبت 10-20 بذور الشعير على طبقتين من ورق الترشيح رطبة في طبق بيتري في ظل ظروف مظلمة لمدة 2 أيام في 22-24 درجة مئوية. قطع جذور قوية مع طول 1-2 سم من البذور باستخدام شفرة حلاقة. </li><li style=";text-align:right;direction:rtl"> تحضير الماء المثلج عن طريق وضع زجاجة 500 مل يحتوي على ماء الصنبور البارد في سحقت الماء المثلج. تهوية الماء المثلج وتغمر نصائح الجذرية لمدة 20 ساعة لزيادة وتيرة الخلايا الطورية. </li><li style=";text-align:right;direction:rtl"> نقل جذور من المياه إلى 50 مل من الايثانول: حامض الخليك (3: 1) تثبيتي لإصلاح لهم في RT لمدة 2 أيام. متجر جذور في الإيثانول الطازجة: حمض الخليك (3: 1) تثبيتي في 4 درجات مئوية حتى استخدام ما يصل إلى سنة. </li></ol></li><li style=";text-align:right;direction:rtl"> غسل وانزيم العلاج <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> غسل 10-20 الجذور مع 30 مل من الجليد الباردة ماء الصنبور لمدة 5 دقائق مرتين باستخدام كوب 50 مل دورق. استخدام المجهر مجهر. نقل جذور واحدا تلو الآخر إلى30 مل 0،01 M عازلة سيترات (0.01 حمض الستريك M + M 0.01 سيترات الصوديوم، ودرجة الحموضة 4.8) باستخدام ملقط، ويغسل عن طريق هز كوب زجاجي لمدة 5 دقائق مرتين. وضع الجذور على الورق مرشح لإزالة السائل تماما وقطع الأنسجة غير بارضي غير مرغوب فيها باستخدام شفرة حلاقة. </li><li style=";text-align:right;direction:rtl"> احتضان ما يصل الى 20 نصائح الجذرية في 1 مل خليط الانزيم عند 37 درجة مئوية لمدة 50 دقيقة لتليين الأنسجة النباتية (الجدول 1) في الزجاج ووتش. يحتوي على خليط انزيم 0.7٪ R10 السيلولوز، 0.7٪ السيلولوز، 1٪ pectolyase و 1٪ cytohelicase مخففة في 0.01 M عازلة سيترات. تخزين خليط الانزيم في -20 ° C وإعادة استخدامها ما يصل الى خمس مرات. </li><li style=";text-align:right;direction:rtl"> إزالة الانزيم من قبل pipetting وغسل نصائح الجذر على الجليد مع 5 مل 0.01 M عازلة سيترات مرتين ليحل محل الانزيم المتبقية. </li></ol></li><li style=";text-align:right;direction:rtl"> النقع الجذر <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> نصائح الجذر غسل مع 1 مل 96٪ من الإيثانول مرتين بعناية في نفس الزجاج ووتش. استبدال الإيثانول مع الطازجة تثبيتي (75٪ حامض الخليك: 25٪ من الإيثانول). استخدام 10-15تثبيتي ميكرولتر في قمة الجذر. </li><li style=";text-align:right;direction:rtl"> نصائح نقل الجذر جنبا إلى جنب مع تثبيتي في أنبوب 2 مل وتتفكك الخلايا الإنشائية الجذر مع إبرة تشريح أو ملقط. الاستفادة من أنبوب 20 مرات لإعادة تعليق الخلايا للحصول على تعليق خلية. تخزين تعليق خلية في -20 ° C تصل إلى شهرين. </li></ol></li><li style=";text-align:right;direction:rtl"> إسقاط تعليق الخلية <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> ضع 2-3 طبقات من المناديل الورقية غارقة في المياه على طبق ساخن عند 50 درجة مئوية. تزج الشرائح المجهرية في مياه الحنفية المثلج في الثلاجة لمدة 30 دقيقة. والشرائح مكان على أعلى من المناديل الورقية الرطبة. </li><li style=";text-align:right;direction:rtl"> ماصة 7-10 ميكرولتر من تعليق خلية وأسقطه من مسافة 20 سم على الشريحة تبريد توضع على طبق ساخن. ماصة 10 ميكرولتر من الخل حامض خليط الإيثانول في نفس المكان تعليق الخلية على الشريحة والحفاظ على الشريحة على طبق ساخن لمدة 2 دقيقة إضافية. وضع الشريحة على طبق ساخن بدون النسيج الرطب واتركها تجف لمدة 1 دقيقة. </li></ol></li><li style=";text-align:right;direction:rtl"> مراقبة الجودة وstorag(ه) من الشرائح <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> تحقق الشرائح باستخدام المجهر المرحلة على النقيض من لمراقبة جودة انتشار كروموسوم. استخدام الشرائح إما في نفس اليوم أو مخزن عن طريق غمر في 96٪ من الإيثانول في وعاء Coplin في -20 ° C. </li></ol></li><li style=";text-align:right;direction:rtl"> المعالجة من قبل الشرائح FISH. تتم جميع الخطوات من في RT <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> مكان الشرائح في جرة Coplin تحتوي على 50 مل من 2X SSC (20x وSSC يحتوي على 3 M كلوريد الصوديوم و 300 ملي سترات الصوديوم) لمدة 5 دقائق. باستخدام ملقط، والشرائح نقل إلى جرة Coplin تحتوي على 50 مل من حمض الخليك 45٪ ل3-10 دقيقة. </li><li style=";text-align:right;direction:rtl"> نقل الشرائح إلى جرة Coplin تحتوي على 50 مل من 2X SSC لمدة 10 دقيقة. الشرائح نقل إلى جرة Coplin تحتوي على 50 مل من 4٪ الفورمالديهايد (في 2X SSC) وتزج الشرائح لمدة 10 دقيقة لإصلاح الصبغيات. </li><li style=";text-align:right;direction:rtl"> إزالة الفورمالديهايد قبل الشطف الشرائح 3 مرات لمدة 4 دقائق لكل منهما، في جرة Coplin تحتوي على 50 مل 2X SSC. يذوى الشرائح في جرة Coplin لمدة 2 دقيقة في سلسلة من 70٪، 90٪ و 100٪ من الإيثانول، على التوالي والشرائح الجافة في رأسيموضع. </li></ol></li></ol> 2. نيون في الموقع التهجين (FISH) <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> لكل شريحة، يعد حل التهجين 20 ميكرولتر في المجموع باستخدام 10 ميكرولتر من الفورماميد منزوع الأيونات، 5 ميكرولتر من العازلة 4X التهجين (200 العازلة ميكرولتر يحتوي على 80 ميكرولتر 20X SSC، 8 ميكرولتر 1 M تريس، حمض الهيدروكلوريك درجة الحموضة 8.0، 1.6 ميكرولتر 0.5 M EDTA، 11.2 ميكرولتر 10 ميكروغرام / ميكرولتر الحيوانات المنوية السلمون و99،2 ميكرولتر خالية من الدناز الماء)، و 3 ميكرولتر من التحقيق و2 ميكرولتر من المياه خالية من الدناز. </li><li style=";text-align:right;direction:rtl"> إضافة 20 ميكرولتر من محلول التهجين لكل شريحة والغطاء مع 24 × 32 مم زلة تغطية وإلقاء القبض على زلة غطاء مع الاسمنت والمطاط. تفسد الشرائح مع تحقيقات في وقت واحد في 80 درجة مئوية لمدة 2 دقيقة على طبق ساخن. </li><li style=";text-align:right;direction:rtl"> نقل الشرائح إلى غرفة رطبة واحتضان الشرائح في 37 ° CO / N ضوء تجنب. إزالة زلات غطاء من قبل الشطف الشرائح في جرة Coplin مع 2X SSC. مكان الشرائح في جرة Coplin تحتوي على 55-60 ° C 2X SSC واحتضان لمدة 20 دقيقة. </li><li style=";text-align:right;direction:rtl"> ضع الشرائح إلى 2x SSC في جرة Coplin لمدة 2 دقيقة في RT. يذوى الشرائح في جرة Coplin لمدة 2 دقيقة في سلسلة من 70٪، 90٪ و 100٪ من الإيثانول، على التوالي. </li><li style=";text-align:right;direction:rtl"> الهواء الجاف الشرائح ومباين مع 1 ميكروغرام / مل 4، 6-diamidino-2-phenylindoline (دابي) في antifade المتوسطة المتزايدة، وتجنب الضوء المكثف. </li></ol> 3. تحليل مجهري والتخزين <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> تحليل الشرائح باستخدام المجهر epifluorescence. اختيار مرشح يعتمد على تألقي تستخدم لوضع العلامات التحقيق. إذا لزم الأمر، والشرائح تخزينها في 4 درجات مئوية تحت الظروف المظلمة تصل الى عام. </li></ol>

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The authors have nothing to disclose.

وقد تم تنفيذ التجربة إعداد كروموسوم من استخدام جذور الشباب من الحبوب تعود لعائلة الأعشاب (النجيلية). جميع الأنواع تحليل لها 14 الإنقسامية طويلة نسبيا الكروموسومات الطورية (11-15 ميكرون) في مجموعة الجينوم مضاعفا وتنتمي إلى الأنواع واسع الجينوم (5،1-7،9 GBP). <p class="jove_content" sty...

مضان التهجين في الموقع (FISH) في هو أداة فعالة لرسم خرائط المادي للتسلسل نسخة واحدة وعالية على مستوى الكروموسومات. شرط أساسي هو إعداد ينتشر كروموسوم جودة عالية. ليس هناك كروموسوم العام إعداد بروتوكول التي من شأنها أن تكون مناسبة أيضا للخلايا الحيوانية والنباتية. إعداد الكروموسومات المصنع هو تحديا من نوع خاص بسبب جدار الخلية جامدة ومختلف الاتساق السيتوبلازم داخل الأنواع المختلفة. إحدى الطرق الملائمة لإعداد الصبغيات النباتية هو ما يسمى تقنية انخفاض المعروف أيضا باسم تقنية الانتشار قطرة وتجفيف الهواء تقنية 1،2. وقدم هذه الطريقة لأول مرة في عام 1958 من قبل Rothfels وSiminovitch لفي المختبر خلايا الثدييات نمت 3. في وقت لاحق مارتن وآخرون. (4) وكاتو وآخرون. 5 تكييف هذه الطريقة للنباتات. وفي الآونة الأخيرة، وهي طريقة تسمى &quot;SteamDrop &amp;# 39؛ وقد وضعت والتي تستخدم البخار المياه لإعداد الكروموسومات غير متداخلة 6. على الرغم من أن لوحظ تأثير إيجابي من ارتفاع نسبة الرطوبة في وقت سابق من 7، &#39;SteamDrop&#39; يسلم سير العمل الخاضعة للرقابة ذات جودة عالية التحضيرات كروموسوم 6. يؤدي العلاج بالبخار تمتد من الكروموسومات ربما تتصل بعض التعديلات من البروتينات الكروموسومات. نوعية الناتج ينتشر الطورية عالية جدا، على الرغم من الاحتفاظ بعدد كاف من الطورية ينتشر كاملة للتجارب FISH اللاحقة يطالب الخبرة التقنية. هنا نقدم بروتوكول لإعداد الكروموسومات الإنقسامية الحبوب مناسبة للكشف FISH من واحد ونسخة عالية تحقيقات 5،8. هذا الأسلوب هو البديل الأفضل للطريقة إسقاط الهواء الجاف وصفه كاتو 9 تتم تحت الرطوبة النسبية من 50٪ -55٪ (الشكل 1). ويتألف هذا البروتوكول عددا أقلغسل خطوات صنع تطبيقه سهلة وفعالة وقابلة للتكرار. باستخدام هذا البروتوكول حصلنا على هوامش كروموسوم ذات جودة عالية ونتائج FISH لفولغاري شعير، H. bulbosum، H. marinum، H. murinum، H. pubiflorum والشيلم cereale.

<table>
	<tbody>
		<tr>
			<td>Hot Plate</td>
			<td>MEDAX GmbH</td>
			<td>12603</td>
			<td></td>
		</tr>
		<tr>
			<td>Cellulase R10</td>
			<td>Duchefa</td>
			<td>C8001</td>
			<td></td>
		</tr>
		<tr>
			<td>Cellulase&#160;</td>
			<td>CalBioChem</td>
			<td>219466</td>
			<td></td>
		</tr>
		<tr>
			<td>Pectolyase</td>
			<td>Sigma</td>
			<td>P3026</td>
			<td></td>
		</tr>
		<tr>
			<td>Cytohelicase</td>
			<td>Sigma</td>
			<td>C8274</td>
			<td></td>
		</tr>
		<tr>
			<td>Texas Red-12-dUTP</td>
			<td>Invitrogen</td>
			<td>C3176</td>
			<td>direct fluorochrome&#160;</td>
		</tr>
		<tr>
			<td>Fluor488-5-dUTP</td>
			<td>Invitrogen</td>
			<td>C11397</td>
			<td>direct fluorochrome&#160;</td>
		</tr>
		<tr>
			<td>Fluorecsence microscope</td>
			<td>Olympus BX61</td>
			<td>BX61</td>
			<td></td>
		</tr>
		<tr>
			<td>CCD camera</td>
			<td>Orca ER, Hamamatsu</td>
			<td>C10600</td>
			<td></td>
		</tr>
		<tr>
			<td>4&#8217;,6-diamidino-2-phenylindole (DAPI)&#160;</td>
			<td>Vector Laboratories</td>
			<td>H-1200</td>
			<td>fluorecsent dye</td>
		</tr>
	</tbody>
</table>

a fast air-dry dropping chromosome preparation method suitable for fish in plants

إعداد ينتشر الكروموسومات هي شرط أساسي لنجاح أداء مضان في الموقع التهجين (FISH). إعداد جودة عالية ينتشر كروموسوم مصنع يمثل تحديا بسبب جدار الخلية جامدة. إحدى الطرق المعتمدة لإعداد الصبغيات النباتية هو ما يسمى إعداد قطرة، المعروف أيضا باسم نشر قطرة أو تقنية تجفيف الهواء. هنا، نقدم بروتوكول لإعداد سريع من كروموسوم الإنقسامية ينتشر مناسبة للكشف FISH تحقيقات DNA نسخة واحدة والعالية. هذا الأسلوب هو البديل الأفضل للطريقة قطرة الهواء الجاف المنفذة بموجب عقد الرطوبة النسبية من 50٪ -55٪. ويتألف هذا البروتوكول انخفاض عدد غسل خطوات صنع تطبيقه سهلة وفعالة وقابلة للتكرار. فوائد واضحة لهذا النهج بشكل جيد الانتشار، الكروموسومات الطورية التالفة والعديد من العاملين كشرط مسبق مثالية لتحليل FISH ناجحة. باستخدام هذا البروتوكول حصلنا عالية الجودة الكرومosome ينتشر والنتائج FISH استنساخه لفولغاري شعير، H. bulbosum، H. marinum، H. murinum، H. pubiflorum والشيلم cereale.

تم إعداد الشرائح المجهرية مع هوامش الطورية الإنقسامية قبل إسقاط الصبغي سريع طريقة التحضير الهواء الجاف هو موضح أعلاه (ملحق الشكل 1). وأجري تحليل FISH من استخدام كليهما، تسلسل المتكررة ونسخة واحدة. وقد تم الحصول على الصور عن طريق المجهر epifluorescence مع مجموعة من الم...

Watch this Scientific Journal Video about A Fast Air-dry Dropping Chromosome Preparation Method Suitable for FISH in Plants at JoVE.com

A Fast Air-dry Dropping Chromosome Preparation Method Suitable for FISH in Plants

A protocol is described for the preparation of high-quality mitotic plant chromosome spreads by a fast air-dry dropping method suitable for the FISH detection of single and high copy DNA probes.

سريع الهواء الجاف اسقاط كروموسوم طريقة التحضير مناسبة لFISH في النباتات

Preparation of chromosome spreads is a prerequisite for the successful performance of fluorescence in situ hybridization (FISH). Preparation of high ...

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13.1K Views.  Leibniz Institute of Plant Genetics and Crop Plant Research (IPK). A protocol is described for the preparation of high-quality mitotic plant chromosome spreads by a fast air-dry dropping method suitable for the FISH detection of single and high copy DNA probes.

Video: A Fast Air-dry Dropping Chromosome Preparation Method Suitable for FISH in Plants

Pyrosequencing: A Simple Method for Accurate Genotyping

Pharmacogenetic research benefits first-hand from the abundance of information provided by the completion of the Human Genome Project. With such a tremendous amount of data available comes an explosion of genotyping methods. Pyrosequencing(R) is one of the most thorough yet simple methods to date used to analyze polymorphisms. It also has the ability to identify tri-allelic, indels, short-repeat polymorphisms, along with determining allele percentages for methylation or pooled sample assessment. In addition, there is a standardized control sequence that provides internal quality control. This method has led to rapid and efficient single-nucleotide polymorphism evaluation including many clinically relevant polymorphisms. The technique and methodology of Pyrosequencing is explained.


Pyrosequencing(R) is one of the most thorough yet simple methods to date used to analyze polymorphisms. This method has led to rapid and efficient single-nucleotide polymorphism evaluation including many clinically relevant polymorphisms. The technique and methodology of Pyrosequencing is explained.

Pyrosequencing : طريقة بسيطة لالتنميط الجيني دقيقة

Pharmacogenetic research benefits first-hand from the abundance of information provided by the completion of the Human Genome Project. With such a ...

Preparation of Drosophila Polytene Chromosome Squashes for Antibody Labeling

Drosophila has long been a favorite model system for studying the relationship between chromatin structure and gene regulation due to the cytological advantages provided by the giant salivary gland polytene chromosomes of third instar larvae.  In this tissue the chromosomes undergo many rounds of replication in the absence of cell division giving rise to approximately 1000 copies.  The DNA remains aligned after each replicative cycle resulting in greatly enlarged chromosomes that provide a unique opportunity to correlate chromatin morphology with the localization of specific proteins.  Consequently, there has been a high level of interest in defining the epigenetic modifications present at different genes and at different stages of the transcription process. An important tool for such studies is the labeling of polytene chromosomes with antibodies to the enzyme, transcription factor, or histone modification of interest. This video protocol illustrates the squash technique used in the Johansen laboratory to prepare Drosophila polytene chromosomes for antibody labeling.

This video protocol illustrates the squash technique used in the Johansen laboratory to prepare Drosophila polytene chromosomes for antibody labeling.

إعداد يسحق ذبابة الفاكهة كروموسوم كثور الخيوط الصبغية للجسم وصفها

Drosophila has long been a favorite model system for studying the relationship between chromatin structure and gene regulation due to the cytological ...

An ex-ovo Chicken Embryo Culture System Suitable for Imaging and Microsurgery Applications

Understanding the relationships between genetic and microenvironmental factors that drive normal and malformed embryonic development is fundamental for discovering new therapeutic strategies. Advancements in imaging technology have enabled quantitative investigation of the organization and maturing of the body plan, but later stage embryonic morphogenesis is less clear. Chicken embryos are an attractive vertebrate animal model system for this application because of its ease of culture and surgical manipulation. Early embryos can be cultured for a short time on filter paper rings, which enables complete optical access for cell patterning and fate studies1,2. Studying advanced developmental processes such as cardiac morphogenesis are traditionally performed through a window of the eggshell3-5, but this technique limits optical access due to window size. We previously developed a simple method to culture whole embryos ex-ovo on hexagonal weigh boats for up to 10 days, which enabled high resolution imaging via ultrasonography6,7. These cultures were difficult to transport, limiting the types of imaging tools available for live experiments. We here present an improved shell-less culture system with a cost-effective, portable environmental chamber. Eggs were cracked onto a hammock created by a polyurethane membrane (cling wrap) affixed circumferentially to a plastic cup partially filled with sterile water. The dimensions of the circumference and depth of the hammock were both critical to maintain surface tension, while the mechanics of the hammock and water beneath helped dampen vibrations induced by transportation. A small footprint circulating water bath was also developed to enable continuous temperature control during experimentation. We demonstrate the ability to culture embryos in this way for at least 14 days without morphogenic defect or delay and employ this system in several microsurgical and imaging applications.

An ex-ovo Chicken Embryo Culture System Suitable for Imaging and Microsurgery Applications

In this article, we present a simple methodology to enable long-term ex-ovo avian embryo culture. This technique is ideal for longitudinal experimentation requiring complete optical accessibility and/or sterile transportation in avian embryos.

و السابقين البيضة الثقافة الأجنة النظام الدجاج مناسبة للتطبيقات التصوير والجراحة المجهرية

Understanding the relationships between genetic and microenvironmental factors that drive normal and malformed embryonic development is fundamental for ...

Ice-Cap: A Method for Growing Arabidopsis and Tomato Plants in 96-well Plates for High-Throughput Genotyping

It is becoming common for plant scientists to develop projects that require the genotyping of large numbers of plants. The first step in any genotyping project is to collect a tissue sample from each individual plant. The traditional approach to this task is to sample plants one-at-a-time. If one wishes to genotype hundreds or thousands of individuals, however, using this strategy results in a significant bottleneck in the genotyping pipeline. The Ice-Cap method that we describe here provides a high-throughput solution to this challenge by allowing one scientist to collect tissue from several thousand seedlings in a single day 1,2. This level of throughput is made possible by the fact that tissue is harvested from plants 96-at-a-time, rather than one-at-a-time.
The Ice-Cap method provides an integrated platform for performing seedling growth, tissue harvest, and DNA extraction. The basis for Ice-Cap is the growth of seedlings in a stacked pair of 96-well plates. The wells of the upper plate contain plugs of agar growth media on which individual seedlings germinate. The roots grow down through the agar media, exit the upper plate through a hole, and pass into a lower plate containing water. To harvest tissue for DNA extraction, the water in the lower plate containing root tissue is rapidly frozen while the seedlings in the upper plate remain at room temperature. The upper plate is then peeled away from the lower plate, yielding one plate with 96 root tissue samples frozen in ice and one plate with 96 viable seedlings. The technique is named "Ice-Cap" because it uses ice to capture the root tissue. The 96-well plate containing the seedlings can then wrapped in foil and transferred to low temperature. This process suspends further growth of the seedlings, but does not affect their viability. Once genotype analysis has been completed, seedlings with the desired genotype can be transferred from the 96-well plate to soil for further propagation. We have demonstrated the utility of the Ice-Cap method using Arabidopsis thaliana, tomato, and rice seedlings. We expect that the method should also be applicable to other species of plants with seeds small enough to fit into the wells of 96-well plates.

Ice-Cap: A Method for Growing Arabidopsis and Tomato Plants in 96-well Plates for High-Throughput Genotyping

The Ice-Cap method allows one to grow plants in 96-well plates and non-destructively harvest root tissue from each seedling. DNA extracted from this root tissue can be used for genotyping reactions. We have found that Ice-Cap works well for Arabidopsis thaliana, tomato, and rice seedlings.

الايس كاب : منهج في تزايد Arabidopsis الطماطم والنباتات في لوحات 96 - جيدا لالرفيع المناولة التنميط الجيني

It is becoming common for plant scientists to develop projects that require the genotyping of large numbers of plants. The first step in any genotyping ...

Chromosome Preparation From Cultured Cells

Chromosome (cytogenetic) analysis is widely used for the detection of chromosome instability. When followed by G-banding and molecular techniques such as fluorescence in situ hybridization (FISH), this assay has the powerful ability to analyze individual cells for aberrations that involve gains or losses of portions of the genome&#160;and rearrangements involving one or more chromosomes. In humans, chromosome abnormalities occur in approximately 1 per 160 live births1,2, 60-80% of all miscarriages3,4, 10% of stillbirths2,5, 13% of individuals with congenital heart disease6, 3-6% of infertility cases2, and in many patients with developmental delay&#160;and birth defects7. Cytogenetic analysis of malignancy is routinely used by researchers and clinicians, as observations of clonal chromosomal abnormalities have been shown to have both diagnostic and prognostic significance8,9.&#160; Chromosome isolation is invaluable for gene therapy and stem cell research of organisms including nonhuman primates and rodents10-13.
Chromosomes can be isolated from cells of live tissues, including blood lymphocytes, skin fibroblasts, amniocytes, placenta, bone marrow, and tumor specimens. Chromosomes are analyzed at the metaphase stage of mitosis, when they are most condensed and therefore more clearly visible. The first step of the chromosome isolation technique involves the disruption of the spindle fibers by incubation with Colcemid, to prevent the cells from proceeding to the subsequent anaphase stage. The cells are then treated with a hypotonic solution and preserved in their swollen state with Carnoy&#39;s fixative. The cells are then dropped on to slides and can then be utilized for a variety of procedures. G-banding involves trypsin treatment followed by staining with Giemsa to create characteristic light and dark bands. The same procedure to isolate chromosomes can be used for the preparation of cells for procedures such as fluorescence in situ hybridization (FISH), comparative genomic hybridization (CGH), and spectral karyotyping (SKY)14,15.

Chromosomes can be isolated from live cells such as lymphocytes or skin fibroblasts, and from organisms including humans or mice. These chromosome preparations can be further utilized for routine G-banding and molecular cytogenetic procedures such as fluorescence in situ hybridization (FISH), comparative genomic hybridization (CGH), and spectral karyotyping (SKY).

إعداد كروموسوم من الخلايا المستزرعة

Chromosome (cytogenetic) analysis is widely used for the detection of chromosome instability. When followed by G-banding and molecular techniques such as ...

Assessing Species-specific Contributions To Craniofacial Development Using Quail-duck Chimeras

The generation of chimeric embryos is a widespread and powerful approach to study cell fates, tissue interactions, and species-specific contributions to the histological and morphological development of vertebrate embryos. In particular, the use of chimeric embryos has established the importance of neural crest in directing the species-specific morphology of the craniofacial complex. The method described herein utilizes two avian species, duck and quail, with remarkably different craniofacial morphology. This method greatly facilitates the investigation of molecular and cellular regulation of species-specific pattern in the craniofacial complex.&#160;Experiments in quail and duck chimeric embryos have already revealed neural crest-mediated tissue interactions and cell-autonomous behaviors that regulate species-specific pattern in the craniofacial skeleton, musculature, and integument. The great diversity of neural crest derivatives suggests significant potential for future applications of the quail-duck chimeric system to understanding vertebrate development, disease, and evolution.

This article describes a method to generate chimeric embryos that are&#160;designed to test the species-specific contributions of neural crest and/or other tissues to craniofacial development.

تقييم مساهمات أنواع محددة لتنمية الجمجمة عن طريق الوهم السمان بطة

The generation of chimeric embryos is a widespread and powerful approach to study cell fates, tissue interactions, and species-specific contributions to ...

Combined DNA-RNA Fluorescent In situ Hybridization (FISH) to Study X Chromosome Inactivation in Differentiated Female Mouse Embryonic Stem Cells

Fluorescent in situ hybridization (FISH) is a molecular technique which enables the detection of nucleic acids in cells. DNA FISH is often used in cytogenetics and cancer diagnostics, and can detect aberrations of the genome, which often has important clinical implications. RNA FISH can be used to detect RNA molecules in cells and has provided important insights in regulation of gene expression. Combining DNA and RNA FISH within the same cell is technically challenging, as conditions suitable for DNA FISH might be too harsh for fragile, single stranded RNA molecules. We here present an easily applicable protocol which enables the combined, simultaneous detection of Xist RNA and DNA encoded by the X chromosomes. This combined DNA-RNA FISH protocol can likely be applied to other systems where both RNA and DNA need to be detected.

Combined DNA-RNA Fluorescent In situ Hybridization FISH to Study X Chromosome Inactivation in Differentiated Female Mouse Embryonic Stem Cells

Fluorescent in situ hybridization (FISH) allows the detection of nucleic acids in their native environment within cells. We here describe a protocol for the combined, simultaneous detection of RNA and DNA by means of FISH, which can be used to study X chromosome inactivation in mouse embryonic stem cells.

الحمض النووي RNA-مجتمعة نيون<em&gt; في الوضع الطبيعي</em&gt; التهجين (FISH) لدراسة كروموسوم X التعطيل في المتباينة أنثى الفأر الخلايا الجذعية الجنينية

Fluorescent in situ hybridization (FISH) is a molecular technique which enables the detection of nucleic acids in cells. DNA FISH is often used in ...

Preparation of Rat Serum Suitable for Mammalian Whole Embryo Culture

Mammalian whole embryo culture (WEC) is a widely used technique for examining pharmacological toxicity in developing mouse and rat embryos and for investigating the mechanisms of developmental processes. Immediately centrifuged (IC) rat serum is commonly used for WEC and is essential for the growth and development of cultured mouse and rat embryos ex vivo. For the culture of midgestation embryos (i.e., E8.0-12.5 for the mouse, and E10.0-14.5 for the rat), 100% rat serum is the best media for supporting the growth of the embryo ex vivo. To prepare rat serum suitable for WEC, the collected blood should be centrifuged immediately to separate the blood cells from the plasma fraction. After centrifugation, the fibrin clot forms in the upper layer; this clot should be squeezed gently using a pair of sterile forceps and subsequently centrifuged to completely separate the blood cells from the serum. In this video article, we demonstrate our standard protocol for the preparation of optimal IC rat serum, including blood collection from the abdominal aorta of male rats and extraction of the serum by centrifugation.

Mammalian whole embryo culture (WEC) is widely used in teratology and developmental biology. Immediately centrifuged rat serum is commonly provided as a medium for both mouse and rat WEC. In this video, we demonstrate our standard protocol for the preparation of high-quality rat serum suitable for mammalian WEC.

إعداد الجرذ مصل مناسب للالثدييات الجامع الثقافة الأجنة

Mammalian whole embryo culture (WEC) is a widely used technique for examining pharmacological toxicity in developing mouse and rat embryos and for ...

Preparation of Meiotic Chromosome Spreads from Mouse Spermatocytes

Mammalian meiosis is a dynamic developmental process that occurs in germ cells and can be studied and characterized. Using a method to spread nuclei on the surface of slides (rather than dropping them from a height), we demonstrate an optimized technique on mouse spermatocytes that was first described in 1997. This method is widely used in laboratories to study mammalian meiosis because it yields a plethora of high quality nuclei undergoing substages of prophase I. Seminiferous tubules are first placed in a hypotonic solution to swell spermatocytes. Then spermatocytes are released into a sucrose solution to create a cell suspension, and nuclei are spread onto fixative-soaked glass slides. Following immunostaining, a diversity of proteins germane to meiotic processes can be examined. For example, proteins of the synaptonemal complex, a tripartite structure that connects the chromosome axes/cores of homologs together can be easily visualized. Meiotic recombination proteins, which are involved in repair of DNA double-strand breaks by homologous recombination, can also be immunostained to evaluate progression of prophase I. Here we describe and demonstrate in detail a technique widely used to study mammalian meiosis in spermatocytes from juvenile or adult male mice.

Meiosis is the developmental process by which gametes are formed through a single round of DNA replication and two successive rounds of chromosome segregation. Mammalian meiosis can be examined by utilizing a technique to prepare meiotic chromosome spreads. Here, we demonstrate a method of preparing surface-spread nuclei from mouse spermatocytes.

إعداد كروموسوم هو ينتشر من الماوس سبيرماتوسيتيس

Mammalian meiosis is a dynamic developmental process that occurs in germ cells and can be studied and characterized. Using a method to spread nuclei on ...

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.

توحيد طريقه غير مميته لتوصيف الحالة الانجابيه وتنميه اليرقات من بلح المياه العذبة (Bivalvia: النقابات)

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