Bu üretim ve deneysel çalışmalar, burada, nazik Lina Aguirre, Gilberto Córdoba, William Mera Ximena Bonilla ve Darío Viveros tarafından desteklenen Reynaldo Pareja, sadık ve coşkulu yardım yansıtır sundu. John Miles ve üç anonim değerlendirenler Ayrıca bize video ve el yazması geliştirmemize yardımcı yorum için teşekkür ederim.

1. Bitkiler <ol><li> Olgun bitkilerden Tek kök kesimler deneysel birimleri olarak kullanılır. Kesimler ekim malzemenin bütünlüğü sağlamak için 10 cm kesilmiş. </li><li> Bitki patojenleri tarafından kirlenmesini önlemek için, 2 dakika süreyle% 3 sodyum hipoklorit solüsyonu kesimler yıkanmış ve thoughroughly sonra musluk suyu ile durulanır. </li><li> Her kesim, yaklaşık olarak dikilir. 36 g (6.5 cm yüksekliği ile dış çapı 5.3 cm) steril toprak silindirik bir PVC boru, plastik bir bardak ile alt ucunda kapalı ve PVC burç ile kaplı. Kesme burç merkezi açılışında yerleştirilen bir köpük halka tarafından yerinde tutulur. </li><li> Yeterli toprak nemi korumak için gerektiği gibi bitkilerin döllenip ve sulandırılmıştır. </li><li> Bitkiler, böcekler tarafından itiraz edilmeden önce, kök ksilem besleme spittlebug perileri siteleri besleme olarak hizmet yüzeysel kökler, gelişimini sağlayacak bir ay boyunca artacak. </li><li> PVC borular köklü çelikler kısmen kök mimari doğasında farklılıklar için ayarlama, daha yüzeysel köklerinin büyümesini uyarmak için önce istilası 8 d için ters. Bu adım, 24 hektar gün için sağladığımız yapay bir ışık kaynağı gerektirir. Bu inversiyon tedavisi deney elimine sonra otobur direnci ile herbivory karıştırıcı kaçar önlemek için, ayrı ayrı bitki, az ya da hiç yüzeysel kökleri ile çoğaltır. Bu eleme temsil ettikleri genotip ortadan kaldırılması için önde gelen hiç seyrek olmalıdır. </li></ol> 2. Haşarat <ol><li> Yetişkin spittlebugs, tarladan toplanan türler tespit ve beslemek için duyarlı brachiariagrasses yaprakları verilmektedir yöntemlerinin koloni kafesleri tanıtıldı. Dişiler yumurtalarını toprakta bulunan kafesler alt tarafında bulunan sığ bir çıkarılabilir tepsi yatıyordu. </li><li> Birkaç gün sonra, toprak suda asılı ve elekler yumurtaları toplamak için bir dizi (42, 60 ve 150 meş) geçirilir. % 30 tuzlu çözüm elenmiş malzeme askıya olgunlaşmamış yumurta ve herhangi bir kalıntı organik madde geride bırakarak, olgun yumurta float neden olur. </li><li> Böcek patojenler tarafından kirlenmesini önlemek için, yumurta, 5 dakika süreyle% 0.5 &#39;lik sodyum hipoklorit solüsyonu dezenfekte ve daha sonra distile su ile durulanır. </li><li> Her bir test tesisi (deneysel birim) altı olgun yumurta ile toprak yüzeyinde musallat. Sadece olgun yumurta kuluçka için yakın enfestasyonlar için seçilir. Kendi arka kısmında pembe işaretleri, böceğin karın bölgesine karşılık; ve tam genişletilmiş operculum&#39;un iki kırmızı böcek gözlerinin ilgili kendi ön kısmı nokta, varlığı ile tespit edilebilir. </li><li> Başarılı kuluçka hangi noktada herhangi bir koloniden bir yenidoğanda spittlebug çıkmamış yumurta yerine, 4 d sonra teyit edilir. </li><li> Test bitkiler genotip başına altı tekrarlamalı tesadüf bir blok tasarımı düzenlenmiştir. </li></ol> 3. Değerlendirmeler <ol><li> Deney yaklaşık değerlendirilir. Sonra 30 gün istilası (kesin kez okudu böcek türlerinin bağlı olarak değişir). </li><li> Hasar 1 gözle görülür hiçbir hasar ve ölü bir bitki (Şekil 1) 5 tekabül karşılık gelen bir görsel ölçek, 1-5 gol. Puanlama bitki zarar hoşgörü bir tahmin sağlar. </li></ol><img src="/files/ftp_upload/3047/3047fig1.jpg" alt="Şekil 1" /> Şekil 1 Brachiaria spp spittlebug herbivory hoşgörü değerlendirmek için kullanılır. Hasar ölçekli. 1 = saptanabilir herhangi bir hasar, 2 =% 0-25 nekrotik yaprakları; 3 =% 25-50 nekrotik yaprakları; 4 =% 50-75 nekrotik yaprakları; 5 =% 75-100 nekrotik yaprakları. <ol start="3"><li> Böcek sağkalım son instar veya yetişkin aşamada (Şekil 2) ulaşan böcekler sayım esasına göre değerlendirilir. Böcek hayatta kalmak için puanlama Antibiyoz bir tahmin sağlar. </li></ol><img src="/files/ftp_upload/3047/3047fig2.jpg" alt="Şekil 2" /> Ilk instar (solda) yetişkin (sağda) Şekil 2 Spittlebug gelişme. Sadece değerlendirme tarihinden en az son instar (oklar) ulaşan böcekler gibi sayılır &quot;hayatta kalanlar.&quot; 4. Temsilcisi sonuçları Spittlebug Aeneolamia reducta direnç için temsili bir tahlil tarama Brachiaria hibritler elde edilen sonuçlar Şekil 3&#39;te sunulmaktadır. <img src="/files/ftp_upload/3047/3047fig3.jpg" alt="Şekil 3" /> Şekil 3 spittlebug Aeneolamia reducta direnç Brachiaria hibritler tarama sonuçları. Herbivory için tepki bu komplo alt yarısında düşerse bitkiler dayanıklı düşünün. Sağdan sola ve yukarıdan aşağıya doğru yükselir hoşgörü Antibiyoz artar. Oklar dayanıklı kontroller noktasında.

<ol>
	<li>Painter, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Insect resistance in crop plants. , (1951).</li><li>Kogan, M., Ortman, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Antixenosis-a+new+term+proposed+to+define+Painter's+'Nonpreference'+modality+of+resistance.">Antixenosis-a new term proposed to define Painter's 'Nonpreference' modality of resistance.</a> Bull. Entomol. Soc. Am. 24, 175-176 (1978).</li><li>Kennedy, G., Gould, F., Deponti, O., Stinner, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ecological,+agricultural,+genetic,+and+commercial+considerations+in+the+deployment+of+insect-resistant+germplasm.">Ecological, agricultural, genetic, and commercial considerations in the deployment of insect-resistant germplasm.</a> Environ. Entomol. 16, 327-338 (1987).</li><li>Holmann, F., Peck, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Economic+damage+of+grassland+spittlebugs+(Homoptera+Cercopidae)+in+Colombia:+a+first+approximation+of+impact+on+animal+production+in+Brachiaria+decumbens.">Economic damage of grassland spittlebugs (Homoptera Cercopidae) in Colombia: a first approximation of impact on animal production in Brachiaria decumbens.</a> Neotrop. Entomol. 31, 275-284 (2002).</li><li>Miles, J. W., Cardona, C., Sotelo, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recurrent+selection+in+a+synthetic+brachiariagrass+population+improves+resistance+to+three+spittlebug+species.">Recurrent selection in a synthetic brachiariagrass population improves resistance to three spittlebug species.</a> Crop Sci. 46, 1088-1093 (2006).</li><li>Ferrufino, A., Lapointe, S. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Host+plant+resistance+in+Brachiaria+grasses+to+the+spittlebug+Zulia+colombiana.">Host plant resistance in Brachiaria grasses to the spittlebug Zulia colombiana.</a> Entomol. Exp. Appl. 51, 155-162 (1989).</li><li>Lapointe, S. L., Serrano, M. S., Arango, G. L., Sotelo, G., Cordoba, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Antibiosis+to+spittlebugs+(Homoptera:+Cercopidae)+in+accessions+of+Brachiaria+spp.">Antibiosis to spittlebugs (Homoptera: Cercopidae) in accessions of Brachiaria spp.</a> J. Econ. Entomol. 82, 1764-1766 (1992).</li><li>Cardona, C., Miles, J. W., Sotelo, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+improved+methodology+for+massive+screening+of+Brachiaria+spp.+genotypes+for+resistance+to+Aeneolamia+varia+(Homoptera:+Cercopidae).">An improved methodology for massive screening of Brachiaria spp. genotypes for resistance to Aeneolamia varia (Homoptera: Cercopidae).</a> J. Econ. Entomol. 92, 490-496 (1999).</li><li>Cardona, C., Fory, P., Sotelo, G., Pabon, A., Diaz, G., Miles, J. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Antibiosis+and+tolerance+to+five+species+of+spittlebug+(Homoptera:+Cercopidae)+in+Brachiaria+spp.:+implications+for+breeding+for+resistance.">Antibiosis and tolerance to five species of spittlebug (Homoptera: Cercopidae) in Brachiaria spp.: implications for breeding for resistance.</a> J. Econ. Entomol. 97, 635-645 (2004).</li><li>Smith, C., Khan, Z., Pathak, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Techniques for evaluating insect resistance in crop plants. , (1994).</li><li>Lapointe, S., Sotelo, G., Arango, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Improved+technique+for+rearing+spittlebugs+(Homoptera:+Cercopidae).">Improved technique for rearing spittlebugs (Homoptera: Cercopidae).</a> J. Econ. Entomol. 82, 1764-1766 (1989).</li><li>Lopez, F., Cardona, C., Miles, J. W., Sotelo, G., Montoya, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Screening+for+resistance+to+adult+spittlebugs+(Hemiptera:+Cercopidae)+in+Brachiaria+spp.:+methods+and+categories+of+resistance.">Screening for resistance to adult spittlebugs (Hemiptera: Cercopidae) in Brachiaria spp.: methods and categories of resistance.</a> J. Econ. Entomol. 102, 1309-1316 (2009).</li></ol>

Otobur direnç mekanizmaları arasında ayrım bitki ıslah çalışmalarının 3 aydınlatmak. Direniş güçlü Antibiyoz dayanarak, bazı durumlarda, daha agresif haşere biotypes için seçim baskısı yaratabilir. Öte yandan, hoşgörüye dayanan direniş hoşgörü sonunda boğulmuş kadar haşere nüfusu artırmak için izin verebilir. Dayanıklı direnci için Hayvancılık, bu nedenle, hangi direnç mekanizmaları, belirli bir ürün / haşere sistemi için en fazla istikrar kazandırmaz [Kennedy ve ark dikkatli bir değerlendirme gerektirir. (1987)] 3 konu hakkında kapsamlı bir tartışma. Bu video gösterisi, Antibiyoz ve hoşgörü brachiariagrasses 6-9 spittlebug direnç göreceli katkıları tahmin etmek için tasarlanmış birkaç önceki çalışmaları üzerine kurar . Seçmeli testler veya tarla denemeleri aksine, no-seçmeli testler, böylece otobur davranış (örneğin, ev sahibi tercihi, toplama) kaynaklanan farklılıklar kontrol sağlayarak, tüm bitkilerin aynı otobur basıncı sağlamak. Bu nedenle, ancak, hayır-seçmeli testler antixenosis direnç değerlendirmek için uygun değildir. , Yapay böcek kolonilerinin yetiştirme direnç tarama testleri 10 test böceklerden elde etmek için tercih edilen bir yöntemdir . Kolonileri 11 yılın herhangi bir zamanında yapılacak deneyler için bilinen bir yaş spittlebugs güvenilir ve düzgün bir kaynak sağlar . Ancak, ilgili alanda nüfus 10 koloni genetik sapma olmadığından emin olmak için periyodik olarak koloninin içine vahşi bireyler demlenmeye gerekli olabilir. Yapay olarak yetiştirilen bu otçul fitness değerlendirmek ve olası değişiklikler zamanla saldırganlık izlemek için, tüm gösterimleri bilinen direnç seviyeleri uygun kontroller çok önemlidir. Uygun bir direnç tarama testinin tasarımı için birden fazla parametre dikkatli bir şekilde tanımlanmış olmalıdır. Test tasarım kabul Birkaç anahtar parametreleri ana bitkilerin yaş, türlerin ve spittlebugs gelişimsel aşamada, istila seviyesi ve bitki-böcek temas 8,9,12 süresi içerir. Deneme ve protokol arıtma birkaç tur alanında yeterince otobur direnci tahmin hızlı, uygun maliyetli, güvenilir, analiz ulaşmak için gerekli olabilir.

characterizing herbivore resistance mechanisms: spittlebugs on brachiaria spp. as an example

Antixenosis, Antibiyoz ve hoşgörü 1: Bitkiler üç geniş mekanizmalar yoluyla otobur hasara karşı koyabilir. Antixenosis otobur diğer bitkiler 2 seçmek için mümkün olduğunda bitki kaçınılmalıdır açısıdır. Antibiyoz bitki bunun 1 beslenen otobur fitness etkiler derecesidir. Hoşgörü bitki otobur büyüme ve üreme 1 ödün vermeden dayanabilir veya otobur yol açtığı hasarı tamir derecesi. Tarımsal bir ortamda otobur direnç dayanıklılığı, bitki yetiştirme çabaları 3 sırasında tercih direnç mekanizmasını büyük ölçüde bağlıdır . Biz, Antibiyoz ve hoşgörü Brachiaria spp spittlebug direnç göreceli katkıları tahmin etmek için tasarlanmış bir hiçbir seçenek deney göstermektedir . Cinsi Brachiaria Afrika otlar birkaç tür Neotropics değerli yem bitkileri ve mera bitkileri, ancak ciddi spittlebugs çeşitli yerli türleri (Hemiptera: Cercopidae) tarafından itiraz edilebilir. Spittlebugs direnci değerlendirmek 4 için, bitkilerin vejetatif yayılır kök kesimler ve spittlebugs yem hangi yüzeysel köklerin büyüme sağlayan, yaklaşık bir ay boyunca büyümeye izin verilir. Bu noktada, her bir test tesisi, kuluçkalık yakın altı spittlebug yumurta ile ayrı ayrı meydan. Salgınlar, bitki hasar ve böcek hayatta kalma değerlendirilmeden önce bir ay boyunca ilerlemeye izin verilir. Böcek hayatta kalma puanlama Antibiyoz bir tahmin sağlar bitki hasar skorlaması hoşgörü bir tahmin sağlar. Bu protokol, ticari brachiariagrases 5 spittlebug direncini artırmak için bitki yetiştirme hedefi kolaylaştırmıştır.

Watch this Scientific Journal Video about Characterizing Herbivore Resistance Mechanisms: Spittlebugs on Brachiaria spp. as an Example at JoVE.com

Characterizing Herbivore Resistance Mechanisms: Spittlebugs on Brachiaria spp. as an Example

Bu video herbivory konak bitki direnç mekanizmaları açıklar ve direnç spittlebug Antibiyoz ve hoşgörü göreceli katkıları tahmin no-seçmeli test gösteren<em&gt; Brachiaria</em&gt; Spp.

Karakterize Otobur Direnç Mekanizmaları: Spittlebugs Brachiaria Spp. Bir Örnek

Plants can resist herbivore damage through three broad mechanisms: antixenosis, antibiosis and tolerance1. Antixenosis is the degree to which the plant is ...

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Characterizing Herbivore Resistance Mechanisms: Spittlebugs on Brachiaria spp. as an Example

13.7K Görüntüleme.  CIAT. Bu video herbivory konak bitki direnç mekanizmaları açıklar ve direnç spittlebug Antibiyoz ve hoşgörü göreceli katkıları tahmin no-seçmeli test gösteren Brachiaria Spp.

Video: Characterizing Herbivore Resistance Mechanisms: Spittlebugs on Brachiaria spp. as an Example

Genetic Studies of Human DNA Repair Proteins Using Yeast as a Model System 

Understanding the roles of human DNA repair proteins in genetic pathways is a formidable challenge to many researchers. Genetic studies in mammalian systems have been limited due to the lack of readily available tools including defined mutant genetic cell lines, regulatory expression systems, and appropriate selectable markers. To circumvent these difficulties, model genetic systems in lower eukaryotes have become an attractive choice for the study of functionally conserved DNA repair proteins and pathways. We have developed a model yeast system to study the poorly defined genetic functions of the Werner syndrome helicase-nuclease (WRN) in nucleic acid metabolism. Cellular phenotypes associated with defined genetic mutant backgrounds can be investigated to clarify the cellular and molecular functions of WRN through its catalytic activities and protein interactions. The human WRN gene and associated variants, cloned into DNA plasmids for expression in yeast, can be placed under the control of a regulatory plasmid element. The expression construct can then be transformed into the appropriate yeast mutant background, and genetic function assayed by a variety of methodologies. Using this approach, we determined that WRN, like its related RecQ family members BLM and Sgs1, operates in a Top3-dependent pathway that is likely to be important for genomic stability. This is described in our recent publication [1] at <a href="http://www.impactaging.com">www.impactaging.com</a>. Detailed methods of specific assays for genetic complementation studies in yeast are provided in this paper.

Genetic Studies of Human DNA Repair Proteins Using Yeast as a Model System

Genetic studies in yeast can be employed to investigate the molecular and cellular functions of human genes in cellular DNA metabolism. Methods are described for the genetic characterization of the human WRN gene product defective in the premature aging disorder Werner syndrome in functionally conserved pathways using yeast as a tractable model system.

İnsan DNA Onarım Proteinler Genetik Araştırmalar Maya Model Sistemi olarak kullanma

Understanding the roles of human DNA repair proteins in genetic pathways is a formidable challenge to many researchers.  Genetic studies in mammalian ...

Biyoloji

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.

Otobur bağlı Blueberry uçucu ve Intra-bitki Sinyalleşme

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

Linking Predation Risk, Herbivore Physiological Stress and Microbial Decomposition of Plant Litter

The quantity and quality of detritus entering the soil determines the rate of decomposition by microbial communities as well as recycle rates of nitrogen (N) and carbon (C) sequestration1,2. Plant litter comprises the majority of detritus3, and so it is assumed that decomposition is only marginally influenced by biomass inputs from animals such as herbivores and carnivores4,5. However, carnivores may influence microbial decomposition of plant litter via a chain of interactions in which predation risk alters the physiology of their herbivore prey that in turn alters soil microbial functioning when the herbivore carcasses are decomposed6. A physiological stress response by herbivores to the risk of predation can change the C:N elemental composition of herbivore biomass7,8,9 because stress from predation risk increases herbivore basal energy demands that in nutrient-limited systems forces herbivores to shift their consumption from N-rich resources to support growth and reproduction to C-rich carbohydrate resources to support heightened metabolism6. Herbivores have limited ability to store excess nutrients, so stressed herbivores excrete N as they increase carbohydrate-C consumption7. Ultimately, prey stressed by predation risk increase their body C:N ratio7,10, making them poorer quality resources for the soil microbial pool likely due to lower availability of labile N for microbial enzyme production6. Thus, decomposition of carcasses of stressed herbivores has a priming effect on the functioning of microbial communities that decreases subsequent ability to of microbes to decompose plant litter6,10,11.
We present the methodology to evaluate linkages between predation risk and litter decomposition by soil microbes. We describe how to: induce stress in herbivores from predation risk; measure those stress responses, and measure the consequences on microbial decomposition. We use insights from a model grassland ecosystem comprising the hunting spider predator (Pisuarina mira), a dominant grasshopper herbivore (Melanoplus femurrubrum),and a variety of grass and forb plants9.

We present methods to evaluate how predation risk can alter the chemical quality of herbivore prey by inducing dietary changes to meet demands of heightened stress, and how the decomposition of carcasses from these stressed herbivores slows subsequent plant litter decomposition by soil microbes.

Predasyon Risk, Herbivore Fizyolojik Stres ve Bitki Çöp mikrobiyal bozunma Bağlama

The quantity and quality of detritus entering the soil  determines the rate of decomposition by microbial communities as well as  recycle rates of ...

Measuring the Osmotic Water Permeability Coefficient (Pf) of Spherical Cells: Isolated Plant Protoplasts as an Example

Studying AQP regulation mechanisms is crucial for the understanding of water relations at both the cellular and the whole plant levels. Presented here is a simple and very efficient method for the determination of the osmotic water permeability coefficient (Pf) in plant protoplasts, applicable in principle also to other spherical cells such as frog oocytes. The first step of the assay is the isolation of protoplasts from the plant tissue of interest by enzymatic digestion into a chamber with an appropriate isotonic solution. The second step consists of an osmotic challenge assay: protoplasts immobilized on the bottom of the chamber are submitted to a constant perfusion starting with an isotonic solution and followed by a hypotonic solution. The cell swelling is video recorded. In the third step, the images are processed offline to yield volume changes, and the time course of the volume changes is correlated with the time course of the change in osmolarity of the chamber perfusion medium, using a curve fitting procedure written in Matlab (the &#8216;PfFit&#8217;), to yield Pf.

Measuring the Osmotic Water Permeability Coefficient Pf of Spherical Cells: Isolated Plant Protoplasts as an Example

Measuring the osmotic water permeability coefficient (Pf) of cells can help understand the regulatory mechanisms of aquaporins (AQPs). Pf determination in spherical plant cell protoplasts presented here involves protoplasts isolation and numerical analysis of their initial rate of volume change as a result of an osmotic challenge during constant bath perfusion.

Ozmotik Su Geçirgenliği Katsayısı (P Ölçme<sub&gt; F</sub&gt;) Küresel Hücreleri: Bir Örnek olarak İzole Bitki protoplastlan

Studying AQP regulation mechanisms is crucial for the understanding of water relations at both the cellular and the whole plant levels. Presented here is ...

The Infiltration-centrifugation Technique for Extraction of Apoplastic Fluid from Plant Leaves Using Phaseolus vulgaris as an Example

The apoplast is a distinct extracellular compartment in plant tissues that lies outside the plasma membrane and includes the cell wall. The apoplastic compartment of plant leaves is the site of several important biological processes, including cell wall formation, cellular nutrient and water uptake and export, plant-endophyte interactions and defence responses to pathogens. The infiltration-centrifugation method is well established as a robust technique for the analysis of the soluble apoplast composition of various plant species. The fluid obtained by this method is commonly known as apoplast washing fluid (AWF). The following protocol describes an optimized vacuum infiltration and centrifugation method for AWF extraction from Phaseolus vulgaris (French bean) cv. Tendergreen leaves. The limitations of this method and the optimization of the protocol for other plant species are discussed. Recovered AWF can be used in a wide range of downstream experiments that seek to characterize the composition of the apoplast and how it varies in response to plant species and genotype, plant development and environmental conditions, or to determine how microorganisms grow in apoplast fluid and respond to changes in its composition.

The Infiltration-centrifugation Technique for Extraction of Apoplastic Fluid from Plant Leaves Using Phaseolus vulgaris as an Example

This protocol details the optimized extraction of apoplast washing fluid from plant leaves, using French bean plants (Phaseolus vulgaris) as a model example.

Tesisinden Akışkan apoplastik çıkarımı için infiltrasyonu-santrifüj Tekniği Kullanarak bırakır<em&gt; Phaseolus vulgaris</em&gt; Bir örnek olarak

The apoplast is a distinct extracellular compartment in plant tissues that lies outside the plasma membrane and includes the cell wall. The apoplastic ...

Imaging FITC-dextran as a Reporter for Regulated Exocytosis

Regulated exocytosis is a process by which cargo, which is stored in secretory granules (SGs), is released in response to a secretory trigger. Regulated exocytosis is fundamental for intercellular communication and is a key mechanism for the secretion of neurotransmitters, hormones, inflammatory mediators, and other compounds, by a variety of cells. At least three distinct mechanisms are known for regulated exocytosis: full exocytosis, where a single SG fully fuses with the plasma membrane, kiss-and-run exocytosis, where a single SG transiently fuses with the plasma membrane, and compound exocytosis, where several SGs fuse with each other, prior to or after SG fusion with the plasma membrane. The type of regulated exocytosis undertaken by a cell is often dictated by the type of secretory trigger. However, in many cells, a single secretory trigger can activate multiple modes of regulated exocytosis simultaneously. Despite their abundance and importance across cell types and species, the mechanisms that determine the different modes of secretion are largely unresolved. One of the main challenges in investigating the different modes of regulated exocytosis, is the difficulty in distinguishing between them as well as exploring them separately. Here we describe the use of fluorescein isothiocyanate (FITC)-dextran as an exocytosis reporter, and live cell imaging, to differentiate between the different pathways of regulated exocytosis, focusing on compound exocytosis, based on the robustness and duration of the exocytic events.

Here we detail a method for live cell imaging of regulated exocytosis. This method utilizes FITC-dextran, which accumulates in lysosome-related organelles, as a reporter. This simple method also allows distinguishing between different modes of regulated exocytosis in cells that are difficult to manipulate genetically.

Düzenlenmiş ekzositozu için muhabir olarak FITC dextran görüntüleme

Regulated exocytosis is a process by which cargo, which is stored in secretory granules (SGs), is released in response to a secretory trigger. Regulated ...

MRM Microcoil Performance Calibration and Usage Demonstrated on Medicago truncatula Roots at 22 T

This protocol describes a signal-to-noise ratio (SNR) calibration and sample preparation method for solenoidal microcoils combined with biological samples, designed for high-resolution magnetic resonance imaging (MRI), also referred to as MR microscopy (MRM). It may be used at pre-clinical MRI spectrometers, demonstrated on Medicago truncatula root samples. Microcoils increase sensitivity by matching the size of the RF resonator to the size of the sample of interest, thereby enabling higher image resolutions in a given data acquisition time. Due to the relatively simple design, solenoidal microcoils are straightforward and cheap to construct and can be easily adapted to the sample requirements. Systematically, we explain how to calibrate new or home-built microcoils, using a reference solution. The calibration steps include: pulse power determination using a nutation curve; estimation of RF-field homogeneity; and calculating a volume-normalized signal-to-noise ratio (SNR) using standard pulse sequences. Important steps in sample preparation for small biological samples are discussed, as well as possible mitigating factors such as magnetic susceptibility differences. The applications of an optimized solenoid coil are demonstrated by high-resolution (13 x 13 x 13 &#956;m3, 2.2 pL) 3D imaging of a root sample.

MRM Microcoil Performance Calibration and Usage Demonstrated on Medicago truncatula Roots at 22 T

A protocol to study biological tissue at high spatial resolution using ultra-high field magnetic resonance microscopy (MRM) using microcoils is presented. Step-by-step instructions are provided for characterizing the microcoils. Finally, optimization of imaging is demonstrated on plant roots.

MRM Microcoil Performans Kalibrasyonu ve Kullanımı Medicago truncatula Köklerinde 22 T'de GösterilmiştiR

This protocol describes a signal-to-noise ratio (SNR) calibration and sample preparation method for solenoidal microcoils combined with biological ...

Exploring m6A and m5C Epitranscriptomes upon Viral Infection: an Example with HIV

The role of RNA modifications in biological processes has been the focus of an increasing number of studies in the last few years and is known nowadays as epitranscriptomics. Among others, N6-methyladenosine (m6A) and 5-methylcytosine (m5C) RNA modifications have been described on mRNA molecules and may have a role in modulating cellular processes. Epitranscriptomics is thus a new layer of regulation that must be considered in addition to transcriptomic analyses, as it can also be altered or modulated by exposure to any chemical or biological agent, including viral infections.
Here, we present a workflow that allows analysis of the joint cellular and viral epitranscriptomic landscape of the m6A and m5C marks simultaneously, in cells infected or not with the human immunodeficiency virus (HIV). Upon mRNA isolation and fragmentation from HIV- infected and non-infected cells, we used two different procedures: MeRIP-Seq, an RNA immunoprecipitation-based technique, to enrich for RNA fragments containing the m6A mark and BS-Seq, a bisulfite conversion-based technique, to identify the m5C mark at a single nucleotide resolution. Upon methylation-specific capture, RNA libraries are prepared for high-throughput sequencing. We also developed a dedicated bioinformatics pipeline to identify differentially methylated (DM) transcripts independently from their basal expression profile.
Overall, the methodology allows exploration of multiple epitranscriptomic marks simultaneously and provides an atlas of DM transcripts upon viral infection or any other cell perturbation. This approach offers new opportunities to identify novel players and novel mechanisms of cell response, such as cellular factors promoting or restricting viral replication.

Exploring m6A and m5C Epitranscriptomes upon Viral Infection: an Example with HIV

The role of RNA modifications in viral infections is just starting to be explored and could highlight new viral-host interaction mechanisms. In this work, we provide a pipeline to investigate m6A and m5C RNA modifications in the context of viral infections.

Viral Enfeksiyon Üzerine m6A ve m5C Epitranscriptomes'i Keşfetmek: HIV ile Bir Örnek

The role of RNA modifications in biological processes has been the focus of an increasing number of studies in the last few years and is known nowadays as ...

Characterizing Mechanical Properties of Primary Cell Wall in Living Plant Organs Using Atomic Force Microscopy

The mechanical properties of the primary cell walls determine the direction and rate of plant cell growth and, therefore, the future size and shape of the plant. Many sophisticated techniques have been developed to measure these properties; however, atomic force microscopy (AFM) remains the most convenient for studying cell wall elasticity at the cellular level. One of the most important limitations of this technique has been that only superficial or isolated living cells can be studied. Here, the use of atomic force microscopy to investigate the mechanical properties of primary cell walls belonging to the internal tissues of a plant body is presented. This protocol describes measurements of the apparent Young&#39;s modulus of cell walls in roots, but the method can also be applied to other plant organs. The measurements are performed on vibratome-derived sections of plant material in a liquid cell, which allows (i) avoiding the use of plasmolyzing solutions or sample impregnation with wax or resin, (ii) making the experiments fast, and (iii) preventing dehydration of the sample. Both anticlinal and periclinal cell walls can be studied, depending on how the specimen was sectioned. Differences in the mechanical properties of different tissues can be investigated in a single section. The protocol describes the principles of study planning, issues with specimen preparation and measurements, as well as the method of selecting force-deformation curves to avoid the influence of topography on the obtained values of elastic modulus. The method is not limited by sample size but is sensitive to cell size (i.e., cells with a large lumen are difficult to examine).

Studies of cell wall biomechanics are essential for understanding plant growth and morphogenesis. The following protocol is proposed to investigate thin primary cell walls in the internal tissues of young plant organs using atomic force microscopy.

Canlı Bitki Organlarında Primer Hücre Duvarının Mekanik Özelliklerinin Atomik Kuvvet Mikroskobu Kullanılarak Karakterize Edilmesi

The mechanical properties of the primary cell walls determine the direction and rate of plant cell growth and, therefore, the future size and shape of the ...

An Electroporation Method to Transform Rickettsia spp. with a Fluorescent Protein-Expressing Shuttle Vector in Tick Cell Lines

Rickettsioses are caused by a broad range of obligate intracellular bacteria belonging to the genus Rickettsia that can be transmitted to vertebrate hosts through the bite of infected arthropod vectors. To date, emerging or re-emerging epidemic rickettsioses remain a public health risk due to the difficulty in diagnosis, as diagnostic methods are limited and not standardized or universally accessible. Misdiagnosis resulting from a lack of recognition of the signs and symptoms may result in delayed antibiotic treatment and poor health outcomes. A comprehensive understanding of Rickettsia characteristics would ultimately improve clinical diagnosis, assessment, and treatment with improved control and prevention of the disease. 
Functional studies of rickettsial genes are crucial for understanding their role in pathogenesis. This paper describes a procedure for the electroporation of the Rickettsia parkeri strain Tate's Hell with the shuttle vector pRAM18dSFA and the selection of transformed R. parkeri in tick cell culture with antibiotics (spectinomycin and streptomycin). A method is also described for the localization of transformed R. parkeri in tick cells using confocal immunofluorescence microscopy, a useful technique for checking transformation in vector cell lines. Similar approaches are also suitable for the transformation of other rickettsiae.

An Electroporation Method to Transform Rickettsia spp. with a Fluorescent Protein-Expressing Shuttle Vector in Tick Cell Lines

Electroporation is a rapid, broadly adopted method for introducing exogenous DNA into the genus Rickettsia. This protocol provides a useful electroporation method for the transformation of obligate intracellular bacteria in the genus Rickettsia.

Kene Hücre Hatlarında Floresan Protein İfade Eden Mekik Vektörü ile Rickettsia spp.'yi Dönüştürmek için Bir Elektroporasyon Yöntemi

Rickettsioses are caused by a broad range of obligate intracellular bacteria belonging to the genus Rickettsia that can be transmitted to vertebrate hosts ...