وأجري هذا البحث في إطار مشروع CRIS USDA-ARS 5325-42000-037-00D ومع النتائج من CRADA 58-3K95-7-1198 و TFCA 58-5325-8-419. المؤلفين الامتنان Suterra عن هدية من (Z، Z) -11،13-hexadecadienal، B. Higbee لمناقشات مثمرة، وجيه بيكر لتقديم المساعدة التقنية.

<ol>
	<li>Bruce, T. J. A., Wadhams, L. J., Woodcock, C. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Insect+host+location:+a+volatile+situation.">Insect host location: a volatile situation.</a> Trends in Plant Sci. 10, 1360-1385 (2005).</li><li>Unsicker, S. B., Kunert, G., Gershenzon, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Protective+perfumes:+the+role+of+vegetative+volatiles+in+plant+defense+against+herbivores.">Protective perfumes: the role of vegetative volatiles in plant defense against herbivores.</a> Curr. Opin. Plant Biol. 12, 479-485 (2009).</li><li>Norin, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Semiochemicals+for+insect+pest+management.">Semiochemicals for insect pest management.</a> Pure Appl. Chem. 79, 2129-2136 (2007).</li><li>Beck, J. J., Merrill, G. B., Higbee, B. S., Light, D. M., Gee, W. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+situ+seasonal+study+of+the+volatile+production+of+almonds+(Prunus+dulcis)+var.+'nonpareil'+and+relationship+to+navel+orangeworm.">In situ seasonal study of the volatile production of almonds (Prunus dulcis) var. 'nonpareil' and relationship to navel orangeworm.</a> J. Agric. Food Chem. 57, 3749-3753 (2009).</li><li>Beck, J. J., Higbee, B. S., Gee, W. S., Dragull, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ambient+orchard+volatiles+from+California+almonds.">Ambient orchard volatiles from California almonds.</a> Phytochem. Lett. 4, 199-202 (2011).</li><li>Coffelt, J. A., Vick, K. W., Sonnet, P. E., Doolittle, R. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation+identification,+and+synthesis+of+a+female+sex+pheromone+of+the+navel+orangeworm,+Amyelois+transitella+(Lepidoptera:+Pyralidae).">Isolation identification, and synthesis of a female sex pheromone of the navel orangeworm, Amyelois transitella (Lepidoptera: Pyralidae).</a> J. Chem. Ecol. 5, 955-933 (1979).</li><li>Leal, W. S., Parra-Pedrazzoli, A. L., Kaissling, K. -. E., Morgan, T. I., Zalom, F. G., Pesak, D. J., Dundulis, E. A., Burks, C. S., Higbee, B. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Unusual+pheromone+chemistry+in+the+navel+orangeworm:+novel+sex+attractants+and+a+behavioral+antagonist.">Unusual pheromone chemistry in the navel orangeworm: novel sex attractants and a behavioral antagonist.</a> Naturwissenschaften. 92, 139-146 (2005).</li><li>Kanno, H., Kuenen, L. P. S., Klingler, K. A., Millar, J. G., Carde, R. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Attractiveness+of+a+four-component+pheromone+blend+to+male+navel+orangeworm+moths.">Attractiveness of a four-component pheromone blend to male navel orangeworm moths.</a> J. Chem. Ecol. 36, 584-591 (2010).</li><li>Takacs, S., Gries, G., Gries, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Semiochemical-mediated+location+of+host+habitat+by+Apanteles+carpatus+(Say)+(Hymenoptera:+Braconidae),+a+parasitoid+of+cloths+moth+larvae.">Semiochemical-mediated location of host habitat by Apanteles carpatus (Say) (Hymenoptera: Braconidae), a parasitoid of cloths moth larvae.</a> J. Chem. Ecol. 23, 459-472 (1997).</li><li>Karimifar, N., Gries, R., Khaskin, G., Gries, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=General+food+semiochemicals+attract+omnivorous+German+cockroaches,+Blattella+germanica.">General food semiochemicals attract omnivorous German cockroaches, Blattella germanica.</a> J. Agric. Food Chem. 59, 1330-1337 (2011).</li><li>Molyneux, R. J., Schieberle, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Compound+identification:+a+Journal+of+Agricultural+and+Food+Chemistry+perspective.">Compound identification: a Journal of Agricultural and Food Chemistry perspective.</a> J. Agric. Food Chem. 55, 4625-4629 (2007).</li><li>Marion-Poll, F., Thiery, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dynamics+of+EAG+responses+to+host-plant+volatiles+delivered+by+a+gas+chromatograph.">Dynamics of EAG responses to host-plant volatiles delivered by a gas chromatograph.</a> Entomol. Exp. Appl. 80, 120-123 (1996).</li><li>Beck, J. J., Higbee, B. S., Merrill, G. B., Roitman, J. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+volatile+emissions+from+undamaged+and+mechanically+damaged+almonds.">Comparison of volatile emissions from undamaged and mechanically damaged almonds.</a> J. Sci. Food Agric. 88, 1363-1368 (2008).</li><li>Lucas, P., Renou, M., Tellier, F., Hammoud, A., Audemard, H., Descoins, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electrophysiology+and+field+activity+of+halogenated+analogs+of+(E,E)-8-10-dodecadien-1-ol,+the+main+pheromone+component+in+codling+moth+(Cydia+pomonella+L.).">Electrophysiology and field activity of halogenated analogs of (E,E)-8-10-dodecadien-1-ol, the main pheromone component in codling moth (Cydia pomonella L.).</a> J. Chem. Ecol. 20, 489-503 (1994).</li><li>Rodriguez-Saona, C., Poland, T. M., Miller, J. R., Stelinski, L. L., Grant, G. G., de Groot, P., Buchan, L., MacDonald, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Behavioral+and+electrophysiological+responses+of+the+emerald+ash+borer,+Agrilus+planipennis,+to+induced+volatiles+of+Manchurian+ash,+Fraxinus+mandshurica.">Behavioral and electrophysiological responses of the emerald ash borer, Agrilus planipennis, to induced volatiles of Manchurian ash, Fraxinus mandshurica.</a> Chemoecology. 16, 75-86 (2006).</li><li>Burks, C. S., Brandl, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Seasonal+abundance+of+navel+orangeworm+(Leipidoptera:+Pyralidae)+in+figs+and+effect+of+peripheral+aerosol+dispensers+on+sexual+communication.">Seasonal abundance of navel orangeworm (Leipidoptera: Pyralidae) in figs and effect of peripheral aerosol dispensers on sexual communication.</a> J. Insect Sci. 4, 1-8 (2004).</li></ol>

المؤلف لديه البحوث التعاونية القائمة والتوصل إلى اتفاق مع شركة تنمية الزراعة باراماونت، وهي شركة لها علاقات LLC Suterra.

استخدام التسجيلات electroantennogram باعتباره الأحيائي لتحديد استجابات استقبال كيميائي من حشرة الهدف هو شائع الى حد كبير ويمكن العثور على العديد من الدراسات التي تستخدم EAG كما كشف عن النفايات السائلة من الغاز اللوني (GC-EAD) في الأدب. أظهرت 9،10 الأسلوب وسوف توفر التشخيص ال...

<table border="1" style=";text-align:right;direction:rtl"><tbody><tr><td> اسم كاشف </td><td> شركة </td><td> فهرس العدد </td><td> تعليقات </td></tr><tr><td> اسيتوفينون </td><td> ألفا، Aesar </td><td> A12727 </td><td> إيجابي سيطرة الإناث </td></tr><tr><td> (Z، Z) -11،13-Hexadecadienal </td><td> Suterra </td><td></td><td> إيجابي سيطرة الذكور </td></tr><tr><td> α-Humulene </td><td> الدريتش </td><td> 53675 </td><td> Sesquiterpene </td></tr><tr><td> 2-Undecanone </td><td> الدريتش </td><td> U1303 </td><td> الأحماض الدهنية المشتقة </td></tr><tr><td> 2-فينيل </td><td> الدريتش </td><td> 77861 </td><td> مركب بنزيني </td></tr><tr><td> البنتان </td><td> EMD </td><td> PX0167-1 </td><td> مذيب </td></tr><tr><td> 4-قناة اكتساب تحكم </td><td> Syntech </td><td> أناDAC-4 </td><td></td></tr><tr><td> EAG التحقيق، قبل مكبر للصوت </td><td> Syntech </td><td> نوع PRG-2 </td><td></td></tr><tr><td> هوائي حامل </td><td> Syntech </td><td> لPRG-2 </td><td> شوكة كهربائي </td></tr><tr><td> التحفيز تحكم </td><td> Syntech </td><td> CS-55 </td><td> تدفق الهواء ونفث </td></tr><tr><td> أطياف الكهربائي جل </td><td> باركر </td><td> 12-02 </td><td></td></tr><tr><td> الأحيائي أقراص </td><td> Whatman </td><td> 2017-006 </td><td> 6 ملم </td></tr><tr><td> باستور pipets </td><td> VWR </td><td> 14673-010 </td><td> 5 ¾ &quot;(14.6 سم) </td></tr><tr><td> Parafilm M </td><td> بيميس </td><td> PM-992 </td><td></td></tr></tbody></table>

electroantennographic bioassay as a screening tool for host plant volatiles

المتطايرة مصنع تلعب دورا هاما في النبات والحشرات التفاعلات. الحشرات العاشبة استخدام المواد المتطايرة نبات، والمعروفة باسم kairomones، لتحديد موقع مصنع المضيفة. 1،2 عند محطة المضيف مهم للتغذية السلع الزراعية ضرر الآفات الحشرية التي يمكن أن تسبب خسائر اقتصادية جسيمة للمزارعين. وفقا لذلك، يمكن استخدام kairomones كما جاذبة لإغراء أو الخلط بين هذه الحشرات، وبالتالي تقديم بديل صديقة للبيئة للمبيدات لمكافحة الحشرات. 3 لسوء الحظ، والنباتات يمكن أن تنبعث من المواد المتطايرة مع عدد كبير تركيبة مختلفة ونسب من الانبعاثات تعتمد على الفينولوجيا للسلعة أو الوقت من اليوم. هذا ما يجعل تحديد المكونات النشطة بيولوجيا، أو مزيج من المكونات المتطايرة عملية شاقة. للمساعدة في تحديد المكونات النشطة بيولوجيا من انبعاثات محطات المضيف المتقلبة التي نتبعها في مختبر فحص الأحيائي القائم على electroantennography (EAG). EAG هو أداة فعالة لتقييم وrecorد electrophysiologically ردود حاسة الشم من حشرة عبر مستقبلاتها antennal. لا يمكن للعملية الفرز EAG يساعد على التقليل من عدد من المواد المتطايرة اختبار لتحديد المكونات النشطة بيولوجيا واعدة. ومع ذلك، اختبارات بيولوجية EAG سوى تقديم المعلومات حول تنشيط المستقبلات. فإنه لا يوفر معلومات حول نوع من سلوك الحشرة مجمع مثير لل، التي يمكن أن تكون بمثابة نوع، جاذبة طارد أو غيرها من استجابة سلوكية. وتؤخذ عادة المتطايرة حصول على استجابة كبيرة من قبل EAG، نسبي للسيطرة على الإيجابية المناسبة، إلى مزيد من التجارب من الاستجابات السلوكية للآفات الحشرية. تصميم تجريبي سوف تعرض بالتفصيل المنهجية المتبعة لفحص اللوز المستندة إلى المواد المتطايرة النبات العائل 4،5 بواسطة قياس ردود antennal الكهربية من شخص بالغ للآفات الحشرية orangeworm السرة (Amyelois transitella) لمكونات واحدة ويمزج بسيط من المكونات عبر EAG الأحيائي. ويستخدم الأسلوب 2 السابقينوضعت هوائيات cised عبر صاحب &quot;شوكة&quot; قطب كهربائي. بروتوكول تظاهر هنا يعرض السريع، والإنتاجية العالية لطريقة موحدة لفحص المواد المتطايرة. كل متقلب هو على المبلغ، ومجموعة ثابتة كما لتوحيد مستوى التحفيز، وبالتالي السماح للردود antennal أن تكون مؤشرا على chemoreceptivity نسبي. سيطرة سلبية تساعد على القضاء على الاستجابة الكهربية لكلا القوة المتبقية المذيبات والميكانيكية للنفخة. السيطرة الايجابية (في هذه اسيتوفينون سبيل المثال) هو مركب واحد التي كانت دافعا لاستجابة متسقة من الذكور والإناث فراشة السرة (الآن) orangeworm. معيار semiochemical الإضافية التي توفر استجابة متسقة ويستخدم للدراسات الأحيائي مع فراشة NOW الذكور (Z، Z) -11،13-hexdecadienal، مكونا الألدهيد من فرمون الإناث المنتجة. 6-8

Watch this Scientific Journal Video about Electroantennographic Bioassay as a Screening Tool for Host Plant Volatiles at JoVE.com

Electroantennographic Bioassay as a Screening Tool for Host Plant Volatiles

وهناك طريقة لالمتطايرة بسرعة شاشة محطة المضيفة عن طريق قياس الاستجابة الكهربية من orangeworm السرة الكبار (<em&gt; Amyelois transitella</emويتجلى&gt;) هوائيات لمكونات واحدة ويمزج عن طريق تحليل electroantennographic.

Electroantennographic الأحيائي كأداة فحص لمواد متطايرة النبات المضيف

Plant volatiles play an important role in plant-insect interactions. Herbivorous insects use plant volatiles, known as kairomones, to locate their host ...

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13.6K Views.  Agricultural Research Service. وهناك طريقة لالمتطايرة بسرعة شاشة محطة المضيفة عن طريق قياس الاستجابة الكهربية من orangeworm السرة الكبار ( Amyelois transitella) هوائيات لمكونات واحدة ويمزج عن طريق تحليل electroantennographic.

Video: Electroantennographic Bioassay as a Screening Tool for Host Plant Volatiles

A &#946;-glucuronidase (GUS) Based Cell Death Assay

We have developed a novel transient plant expression system that simultaneously expresses the reporter gene, &beta;-glucuronidase (GUS), with putative positive or negative regulators of cell death. In this system, N. benthamiana leaves are co-infiltrated with a 35S driven expression cassette containing the gene to be analyzed, and the GUS vector pCAMBIA 2301 using Agrobacterium strain LBA4404 as a vehicle. Because live cells are required for GUS expression to occur, loss of GUS activity is expected when this marker gene is co-expressed with positive regulators of cell death. Equally, increased GUS activity is observed when anti-apoptotic genes are used compared to the vector control. As shown below, we have successfully used this system in our lab to analyze both pro- and anti-death players. These include the plant anti-apoptotic Bcl-2 Associated athanoGene (BAG) family, as well as, known mammalian inducers of cell death, such as BAX. Additionally, we have used this system to analyze the death function of specific truncations within proteins, which could provide clues on the possible post-translational modification/activation of these proteins. Here, we present a rapid and sensitive plant based method, as an initial step in investigating the death function of specific genes.

A &#946;-glucuronidase GUS Based Cell Death Assay

Programmed cell death assays commonly used in mammalian systems such as DNA laddering or TUNEL assays, are often difficult to reproduce in plants. In combination with a GUS reporter system, we propose a rapid, plant based transient assay to analyze the potential death properties of specific genes.

A β غلوكورونيداز (GUS) موت الخلية استنادا الفحص

We have developed a novel transient plant expression system that simultaneously expresses the reporter gene, &beta;-glucuronidase (GUS), with putative ...

Herbivore-induced Blueberry Volatiles and Intra-plant Signaling

Herbivore-induced plant volatiles (HIPVs) are commonly emitted from plants after herbivore attack1,2. These HIPVs are mainly regulated by the defensive plant hormone jasmonic acid (JA) and its volatile derivative methyl jasmonate (MeJA)3,4,5. Over the past 3 decades researchers have documented that HIPVs can repel or attract herbivores, attract the natural enemies of herbivores, and in some cases they can induce or prime plant defenses prior to herbivore attack. In a recent paper6, I reported that feeding by gypsy moth caterpillars, exogenous MeJA application, and mechanical damage induce the emissions of volatiles from blueberry plants, albeit differently. In addition, blueberry branches respond to HIPVs emitted from neighboring branches of the same plant by increasing the levels of JA and resistance to herbivores (i.e., direct plant defenses), and by priming volatile emissions (i.e., indirect plant defenses). Similar findings have been reported recently for sagebrush7, poplar8, and lima beans9..
Here, I describe a push-pull method for collecting blueberry volatiles induced by herbivore (gypsy moth) feeding, exogenous MeJA application, and mechanical damage. The volatile collection unit consists of a 4 L volatile collection chamber, a 2-piece guillotine, an air delivery system that purifies incoming air, and a vacuum system connected to a trap filled with Super-Q adsorbent to collect volatiles5,6,10. Volatiles collected in Super-Q traps are eluted with dichloromethane and then separated and quantified using Gas Chromatography (GC). This volatile collection method was used n my study6 to investigate the volatile response of undamaged branches to exposure to volatiles from herbivore-damaged branches within blueberry plants. These methods are described here. Briefly, undamaged blueberry branches are exposed to HIPVs from neighboring branches within the same plant. Using the same techniques described above, volatiles emitted from branches after exposure to HIPVs are collected and analyzed.

A push-pull method for collecting plant volatiles is described. The method allows for a comparison of volatiles induced by herbivore feeding, exogenous methyl jasmonate, and mechanical damage. This technique is also used to investigate the volatile response of undamaged branches to exposure to volatiles from herbivore-damaged branches within blueberry plants.

عاشب متطايرة بفعل العنبية واشارة الى داخل المصنع

Herbivore-induced plant volatiles (HIPVs) are commonly emitted from plants after herbivore attack1,2.  These HIPVs are mainly regulated by the defensive ...

Fluorescence-microscopy Screening and Next-generation Sequencing: Useful Tools for the Identification of Genes Involved in Organelle Integrity

This protocol describes a fluorescence microscope-based screening of Arabidopsis seedlings and describes how to map recessive mutations that alter the subcellular distribution of a specific tagged fluorescent marker in the secretory pathway. Arabidopsis is a powerful biological model for genetic studies because of its genome size, generation time, and conservation of molecular mechanisms among kingdoms. The array genotyping as an approach to map the mutation in alternative to the traditional method based on molecular markers is advantageous because it is relatively faster and may allow the mapping of several mutants in a really short time frame. This method allows the identification of proteins that can influence the integrity of any organelle in plants. Here, as an example, we propose a screen to map genes important for the integrity of the endoplasmic reticulum (ER). Our approach, however, can be easily extended to other plant cell organelles (for example see1,2), and thus represents an important step toward understanding the molecular basis governing other subcellular structures.

A fundamental quest in cell biology is to define the mechanisms that underlie the identity of the organelles that make eukaryotic cells. Here we propose a method to identify the genes responsible for the morphological and functional integrity of plant organelles using fluorescence microscopy and next-generation sequencing tools.

مضان-المجهري الفحص والجيل القادم التسلسل الجيني: أدوات مفيدة لتحديد الجينات المسؤولة عن النزاهة العضيم

This protocol describes a fluorescence microscope-based screening of Arabidopsis seedlings and describes how to map recessive mutations that alter the ...

Using SecM Arrest Sequence as a Tool to Isolate Ribosome Bound Polypeptides

Extensive research has provided ample evidences suggesting that protein folding in the cell is a co-translational process1-5. However, the exact pathway that polypeptide chain follows during co-translational folding to achieve its functional form is still an enigma. In order to understand this process and to determine the exact conformation of the co-translational folding intermediates, it is essential to develop techniques that allow the isolation of RNCs carrying nascent chains of predetermined sizes to allow their further structural analysis.
SecM (secretion monitor) is a 170 amino acid E. coli protein that regulates expression of the downstream SecA (secretion driving) ATPase in the secM-secA operon6. Nakatogawa and Ito originally found that a 17 amino acid long sequence (150-FSTPVWISQAQGIRAGP-166) in the C-terminal region of the SecM protein is sufficient and necessary to cause stalling of SecM elongation at Gly165, thereby producing peptidyl-glycyl-tRNA stably bound to the ribosomal P-site7-9. More importantly, it was found that this 17 amino acid long sequence can be fused to the C-terminus of virtually any full-length and/or truncated protein thus allowing the production of RNCs carrying nascent chains of predetermined sizes7. Thus, when fused or inserted into the target protein, SecM stalling sequence produces arrest of the polypeptide chain elongation and generates stable RNCs both in vivo in E. coli cells and in vitro in a cell-free system. Sucrose gradient centrifugation is further utilized to isolate RNCs.
The isolated RNCs can be used to analyze structural and functional features of the co-translational folding intermediates. Recently, this technique has been successfully used to gain insights into the structure of several ribosome bound nascent chains10,11. Here we describe the isolation of bovine Gamma-B Crystallin RNCs fused to SecM and generated in an in vitro translation system.

We describe here a technique that is now routinely used to isolate stably bound ribosome nascent chain complexes (RNCs). This technique takes advantage of the discovery that a 17 amino acid long SecM "arrest sequence" can halt translation elongation in a prokaryotic (E. coli) system, when inserted into (or fused to the C-terminus) of virtually any protein.

باستخدام SecM تسلسل توقيف كأداة لعزل البروتينية منضم ريبوسوم

Extensive research has provided ample evidences suggesting that protein folding in the cell is a co-translational process1-5. However, the exact pathway ...

RNA Catalyst as a Reporter for Screening Drugs against RNA Editing in Trypanosomes

Substantial progress has been made in determining the mechanism of mitochondrial RNA editing in trypanosomes. Similarly, considerable progress has been made in identifying the components of the editosome complex that catalyze RNA editing. However, it is still not clear how those proteins work together. Chemical compounds obtained from a high-throughput screen against the editosome may block or affect one or more steps in the editing cycle. Therefore, the identification of new chemical compounds will generate valuable molecular probes for dissecting the editosome function and assembly. In previous studies, in vitro editing assays were carried out using radio-labeled RNA. These assays are time consuming, inefficient and unsuitable for high-throughput purposes. Here, a homogenous fluorescence-based &#8220;mix and measure&#8221; hammerhead ribozyme in vitro reporter assay to monitor RNA editing, is presented. Only as a consequence of RNA editing of the hammerhead ribozyme a fluorescence resonance energy transfer (FRET) oligoribonucleotide substrate undergoes cleavage. This in turn results in separation of the fluorophore from the quencher thereby producing a signal. In contrast, when the editosome function is inhibited, the fluorescence signal will be quenched. This is a highly sensitive and simple assay that should be generally applicable to monitor in vitro RNA editing or high throughput screening of chemicals that can inhibit the editosome function.

A highly sensitive ribozyme-based assay, applicable to high-throughput screening of chemicals targeting the unique process of RNA editing in trypanosomatid pathogens, is described in this paper. Inhibitors can be used as tools for hypothesis-driven analysis of the RNA editing process and ultimately as therapeutics.

RNA محفز كمراسلة لفحص الحمض النووي الريبي أدوية ضد التحرير في المثقبيات

Substantial progress has been made in determining the mechanism of mitochondrial RNA editing in trypanosomes. Similarly, considerable progress has been ...

High-throughput Screening for Chemical Modulators of Post-transcriptionally Regulated Genes

Both transcriptional and post-transcriptional regulation have a profound impact on genes expression. However, commonly adopted cell-based screening assays focus on transcriptional regulation, being essentially aimed at the identification of promoter-targeting molecules. As a result, post-transcriptional mechanisms are largely uncovered by gene expression targeted drug development. Here we describe a cell-based assay aimed at investigating the role of the 3&#39; untranslated region (3&#8217; UTR) in the modulation of the fate of its mRNA, and at identifying compounds able to modify it. The assay is based on the use of a luciferase reporter construct containing the 3&#8217; UTR of a gene of interest stably integrated into a disease-relevant cell line. The protocol is divided into two parts, with the initial focus on the primary screening aimed at the identification of molecules affecting luciferase activity after 24 hr of treatment. The second part of the protocol describes the counter-screening necessary to discriminate compounds modulating luciferase activity specifically through the 3&#8217; UTR. In addition to the detailed protocol and representative results, we provide important considerations about the assay development and the validation of the hit(s) on the endogenous target. The described cell-based reporter gene assay will allow scientists to identify molecules modulating protein levels via post-transcriptional mechanisms dependent on a 3&#8217; UTR.

Here we describe a cell-based reporter gene assay as a valuable tool to screen chemical libraries for compounds modulating post-transcriptional control mechanisms exerted through 3&#8217; UTR.

الإنتاجية العالية للكشف عن المغيرون الكيميائية من الجينات المشاركة ما بعد transcriptionally الخاضعة للرقابة

Both transcriptional and post-transcriptional regulation have a profound impact on genes expression. However, commonly adopted cell-based screening assays ...

A Simple Bioassay for the Evaluation of Vascular Endothelial Growth Factors

The analysis of receptor tyrosine kinases and their interacting ligands involved in vascular biology is often challenging due to the constitutive expression of families of related receptors, a broad range of related ligands and the difficulty of dealing with primary cultures of specialized endothelial cells. Here we describe a bioassay for the detection of ligands to the vascular endothelial growth factor receptor-2 (VEGFR-2), a key transducer of signals that promote angiogenesis and lymphangiogenesis. A cDNA encoding a fusion of the extracellular (ligand-binding) region of VEGFR-2 with the transmembrane and cytoplasmic regions of the erythropoietin receptor (EpoR) is expressed in the factor-dependent cell line Ba/F3. This cell line grows in the presence of interleukin-3 (IL-3) and withdrawal of this factor results in death of the cells within 24 hr. Expression of the VEGFR-2/EpoR receptor fusion provides an alternative mechanism to promote survival and potentially proliferation of stably transfected Ba/F3 cells in the presence of a ligand capable of binding and cross-linking the extracellular portion of the fusion protein (i.e., one that can cross-link the VEGFR-2 extracellular region). The assay can be performed in two ways: a semi-quantitative approach in which small volumes of ligand and cells permit a rapid result in 24 hr, and a quantitative approach involving surrogate markers of a viable cell number. The assay is relatively easy to perform, is highly responsive to known VEGFR-2 ligands and can accommodate extracellular inhibitors of VEGFR-2 signaling such as monoclonal antibodies to the receptor or ligands, and soluble ligand traps.

We describe a simple cell-based bioassay for detecting, quantifying and monitoring the activity of members of the vascular endothelial growth factor family of ligands. The assay uses chimeric receptors expressed in a factor-dependent cell line to provide a semi-quantitative or quantitative assessment of receptor binding and cross-linking by the ligand.

والأحيائي بسيط لتقييم العوامل الأوعية الدموية غشائي النمو

The analysis of receptor tyrosine kinases and their interacting ligands involved in vascular biology is often challenging due to the constitutive ...

Laser-assisted Microdissection (LAM) as a Tool for Transcriptional Profiling of Individual Cell Types

The understanding of developmental processes at the molecular level requires insights into transcriptional regulation, and thus the transcriptome, at the level of individual cell types. While the methods described here are generally applicable to a wide range of species and cell types, our research focuses on plant reproduction. Plant cultivation and seed production is of crucial importance for human and animal nutrition. A detailed understanding of the regulatory networks that govern the formation of the reproductive lineage (germline) and ultimately of seeds is a precondition for the targeted manipulation of plant reproduction. In particular, the engineering of apomixis (asexual reproduction through seeds) into crop plants promises great improvements, as it leads to the formation of clonal seeds that are genetically identical to the mother plant. Consequently, the cell types of the female germline are of major importance for the understanding and engineering of apomixis. However, as the corresponding cells are deeply embedded within the floral tissues, they are very difficult to access for experimental analyses, including cell-type specific transcriptomics. To overcome this limitation, sections of individual cells can be isolated by laser-assisted microdissection (LAM). While LAM in combination with transcriptional profiling allows the identification of genes and pathways active in any cell type with high specificity, establishing a suitable protocol can be challenging. Specifically, the quality of RNA obtained after LAM can be compromised, especially when small, single cells are targeted. To circumvent this problem, we have established a workflow for LAM that reproducibly results in high RNA quality that is well suitable for transcriptomics, as exemplified here by the isolation of cells of the female germline in apomictic Boechera. In this protocol, procedures are described for tissue preparation and LAM, also with regard to RNA extraction and quality control.

Laser-assisted Microdissection LAM as a Tool for Transcriptional Profiling of Individual Cell Types

Here we present a protocol for laser-assisted microdissection of specific plant cell types for transcriptional profiling. While the protocol is suitable for different species and cell types, the focus is on highly inaccessible cells of the female germline important for sexual and apomictic reproduction in the crucifer genus Boechera.

بمساعدة الليزر تسليخ مجهري (لام) كأداة للالترانسكربتي التنميط من أنواع الخلايا الفردية

The understanding of developmental processes at the molecular level requires insights into transcriptional regulation, and thus the transcriptome, at the ...

A Plate Competition Assay As a Quick Preliminary Assessment of Disease Suppression

The goal was to develop and optimize a simple, affordable, and effective bioassay to detect disease suppressive ability of a specific compost against soilborne fungus Rhizoctonia solani. R. solani is a pathogen of a wide range of plant hosts worldwide. The fungus survives in soils as a saprophyte and grows rapidly on simple water agar media. The plate assay is a rapid method to compare composts for their ability to slow the growth of R. solani. The assay also correlates well with suppression of other soilborne fungal pathogens that survive as saprophytes in soils such as Alternaria early blights, Fusarium wilt, Phytophthora root rot, and Pythium root rot.

Presented is a protocol for a plate competition assay to identify whether a specific compost is likely to contain bacteria and fungi that suppress growth of Rhizoctonia solani.

لوح منافسة مقايسة كتقييم أولى سريع لقمع المرض

The goal was to develop and optimize a simple, affordable, and effective bioassay to detect disease suppressive ability of a specific compost against ...

Transposon-insertion Sequencing as a Tool to Elucidate Bacterial Colonization Factors in a Burkholderia gladioli Symbiont of Lagria villosa Beetles

Inferring the function of genes by manipulating their activity is an essential tool for understanding the genetic underpinnings of most biological processes. Advances in molecular microbiology have seen the emergence of diverse mutagenesis techniques for the manipulation of genes. Among them, transposon-insertion sequencing (Tn-seq) is a valuable tool to simultaneously assess the functionality of many candidate genes in an untargeted way. The technique has been key to identify&#160;molecular mechanisms for the colonization of eukaryotic hosts in several pathogenic microbes and a few beneficial symbionts.
Here, Tn-seq is established as a method to identify colonization factors in a mutualistic Burkholderia gladioli symbiont of the beetle Lagria villosa. By conjugation, Tn5 transposon-mediated insertion of an antibiotic-resistance cassette is&#160;carried out at random genomic locations in B. gladioli. To identify the effect of gene disruptions on the ability of the bacteria to colonize the beetle host, the generated B. gladioli transposon-mutant library is inoculated on the beetle eggs, while a control is grown in vitro in a liquid culture medium. After allowing sufficient time for colonization, DNA is extracted from the in vivo and in vitro grown libraries. Following a DNA library preparation protocol, the DNA samples are prepared for transposon-insertion sequencing. DNA fragments that contain the transposon-insert edge and flanking bacterial DNA are selected, and the mutation sites are determined by sequencing away from the transposon-insert edge. Finally, by analyzing and comparing the frequencies of each mutant between the in vivo and in vitro libraries, the importance of specific symbiont genes during beetle colonization can be predicted.

Transposon-insertion Sequencing as a Tool to Elucidate Bacterial Colonization Factors in a Burkholderia gladioli Symbiont of Lagria villosa Beetles

This is an adapted method for identifying candidate insect colonization factors in a Burkholderia beneficial symbiont. The beetle host is infected with a random mutant library generated via transposon mutagenesis, and library complexity after colonization is compared to a control grown in vitro.