Somos gratos a Sabin Russell para a assistência edição. Este trabalho fez parte do Instituto Joint BioEnergy DOE (http://www.jbei.org), apoiado pelo Departamento de Energia dos EUA, Escritório de Ciência, Instituto de Pesquisa Ambiental e Biológica, por meio do contrato DE-AC02-05CH11231 entre Lawrence Berkeley Laboratório Nacional e do Departamento de Energia dos EUA.

<ol>
	<li>Boerjan, W., Ralph, J., Baucher, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lignin+biosynthesis.">Lignin biosynthesis.</a> Annual review of plant biology. 54, 519-546 (2003).</li><li>Vanholme, R., Demedts, B., Morreel, K., Ralph, J., Boerjan, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lignin+biosynthesis+and+structure.">Lignin biosynthesis and structure.</a> Plant physiology. 153, 895-905 (2010).</li><li>Humphreys, J. M., Chapple, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rewriting+the+lignin+roadmap.">Rewriting the lignin roadmap.</a> Current opinion in plant biology. 5, 224-229 (2002).</li><li>Adler, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lignin+chemistry&#8212;past,+present+and+future.">Lignin chemistry&#8212;past, present and future.</a> Wood Sci. Technol. 11, 169-218 (1977).</li><li>Brien, T. P., Feder, N., McCully, M. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Polychromatic+Staining+of+Plant+Cell+Walls+by+Toluidine+Blue.">Polychromatic Staining of Plant Cell Walls by Toluidine Blue.</a> 59, 368-373 (1964).</li><li>Mori, B., Bellani, L. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Differential+staining+for+cellulosic+and+modified+plant+cell+walls.">Differential staining for cellulosic and modified plant cell walls.</a> Biotechnic &amp; histochemistry: official publication of the Biological Stain Commission. 71, 71-72 (1996).</li><li>Maeda, H., Ishida, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Specificity+of+binding+of+hexopyranosyl+polysaccharides+with+fluorescent+brightener.">Specificity of binding of hexopyranosyl polysaccharides with fluorescent brightener.</a> Journal of biochemistry. 62, 276-278 (1967).</li><li>Wood, P. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Specificity+in+the+interaction+of+direct+dyes+with+polysaccharides.">Specificity in the interaction of direct dyes with polysaccharides.</a> Carbohydrate Research. 85, 271-287 (1980).</li><li>Hughes, J., McCully, M. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+use+of+an+optical+brightener+in+the+study+of+plant+structure.">The use of an optical brightener in the study of plant structure.</a> Stain technology. 50, 319-329 (1975).</li><li>Verbelen, J. P., Kerstens, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Polarization+confocal+microscopy+and+congo+red+fluorescence:+a+simple+and+rapid+method+to+determine+the+mean+cellulose+fibril+orientation+in+plants.">Polarization confocal microscopy and congo red fluorescence: a simple and rapid method to determine the mean cellulose fibril orientation in plants.</a> Journal of microscopy. 198, 101-107 (2000).</li><li>Anderson, C. T., Carroll, A., Akhmetova, L., Somerville, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Real-time+imaging+of+cellulose+reorientation+during+cell+wall+expansion+in+Arabidopsis+roots.">Real-time imaging of cellulose reorientation during cell wall expansion in Arabidopsis roots.</a> Plant physiology. 152, 787-796 (2010).</li><li>Liljegren, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Phloroglucinol+Stain+for+Lignin.">Phloroglucinol Stain for Lignin.</a> Cold Spring Harbor Protocols. , (2010).</li><li>Nakano, J., Meshitsuka, G., lin, S., Dence, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> The Detection of Lignin Methods in Lignin Chemistry. , (1992).</li><li>Sibout, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=CINNAMYL+ALCOHOL+DEHYDROGENASE-C+and+-D+are+the+primary+genes+involved+in+lignin+biosynthesis+in+the+floral+stem+of+Arabidopsis.">CINNAMYL ALCOHOL DEHYDROGENASE-C and -D are the primary genes involved in lignin biosynthesis in the floral stem of Arabidopsis.</a> The Plant cell. 17, 2059-2076 (2005).</li><li>Teather, R. M., Wood, P. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+Congo+red-polysaccharide+interactions+in+enumeration+and+characterization+of+cellulolytic+bacteria+from+the+bovine+rumen.">Use of Congo red-polysaccharide interactions in enumeration and characterization of cellulolytic bacteria from the bovine rumen.</a> Applied and environmental microbiology. 43, 777-780 (1982).</li><li>Yeung, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+beginner's+guide+to+the+study+of+plant+structure.">A beginner's guide to the study of plant structure.</a> Proceedings of the 19th Workshop/Conference of the Association for Biology Laboratory Education (ABLE. 19, 365-36 (1998).</li><li>Turner, S. R., Somerville, C. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Collapsed+xylem+phenotype+of+Arabidopsis+identifies+mutants+deficient+in+cellulose+deposition+in+the+secondary+cell+wall).">Collapsed xylem phenotype of Arabidopsis identifies mutants deficient in cellulose deposition in the secondary cell wall).</a> The Plant Cell Online. 9, 689-701 (1997).</li><li>Iiyama, K., Pant, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+mechanism+of+the+M&#228;ule+colour+reaction.+Introduction+of+methylated+syringyl+nuclei+into+softwood+lignin.">The mechanism of the M&#228;ule colour reaction. Introduction of methylated syringyl nuclei into softwood lignin.</a> Wood Sci. Technol. 22, 167-175 (1988).</li><li>Yang, F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Engineering+secondary+cell+wall+deposition+in+plants.">Engineering secondary cell wall deposition in plants.</a> Plant biotechnology journal. 11, 325-335 (2013).</li><li>Zhong, R., Ripperger, A., Ye, Z. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ectopic+deposition+of+lignin+in+the+pith+of+stems+of+two+Arabidopsis+mutants.">Ectopic deposition of lignin in the pith of stems of two Arabidopsis mutants.</a> Plant physiology. 123, 59-70 (2000).</li><li>Chapple, C. C., Vogt, T., Ellis, B. E., Somerville, C. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+Arabidopsis+mutant+defective+in+the+general+phenylpropanoid+pathway.">An Arabidopsis mutant defective in the general phenylpropanoid pathway.</a> The Plant cell. 4, 1413-1424 (1992).</li><li>Fagard, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=PROCUSTE1+Encodes+a+Cellulose+Synthase+Required+for+Normal+Cell+Elongation+Specifically+in+Roots+and+Dark-Grown+Hypocotyls+of+Arabidopsis.">PROCUSTE1 Encodes a Cellulose Synthase Required for Normal Cell Elongation Specifically in Roots and Dark-Grown Hypocotyls of Arabidopsis.</a> The Plant Cell Online. 12, 2409-2423 (2000).</li></ol>

The authors have no financial conflicts to disclose.

Secções tronco de A. thaliana são amplamente usados ​​para o estudo da organização das células da parede celular secundária e para examinar qualitativamente as diferenças entre o tipo selvagem e plantas transgénicas. As técnicas comumente utilizadas para a secção dos espécimes são corte manual direta; ou quando as amostras são incorporados em agarose ou fixador, o seccionamento pode ser feito com um vibratome ou micrótomo. Em contraste com o lado de corte, os dois últimos permitem reduzir o...

A parede celular da planta tem uma infinidade de informações dentro de seus vários componentes: lignina, celulose, hemicelulose (xilana, glucuronoxylan, xiloglucano, arabinoxilano, ligação mista glucana, ou glucomanana) e pectina. Técnicas histológicas fornecer dicas visuais importantes no estudo das diferenças dentro das paredes celulares secundárias a nível da organização e celulares. Várias técnicas histológicas foram desenvolvidos e podem ser encontrados na literatura, mas estas técnicas pode ser um desafio para principiantes e demorada porque os protocolos muito detalhado com instruções visuais simples são raramente, se alguma vez disponível. O objetivo deste estudo é fornecer orientações simples para técnicas de coloração histológicas para obter imagens de alta qualidade. Seccionamento do tecido do tronco é o primeiro passo para a visualização de células e paredes celulares de formas. Embora seções cortados à mão são baratos e levam menos tempo para se preparar, o uso de um vibratome oferece consistência eproduz imagens de alta qualidade. Usando um vibratome permite produzir melhor qualidade de dados, gerando até secções com a mesma espessura, o que ajuda a produzir imagens nítidas e reduz significativamente o risco de produzir diferenças entre amostras imprecisos que seria simplesmente causada por uma preparação de amostra mau. Usando resinas para fixar espécimes frescos pode ser um desafio para iniciantes e ainda pode ser demorado, mesmo para especialistas, quando uma análise precisa ser feito rapidamente. Além disso, torna-se impossível de medir qualquer actividade biológica com a amostra quando tiver sido incorporado numa resina. Uma técnica simples que emprega um molde de agarose e caseiro é útil para a incorporação de tecidos do caule, e que também pode ser utilizado em outras aplicações que requerem uma dissecção de tecidos moles. Em comparação com a incorporação de espécimes em resina, este método tem a vantagem de manter os tecidos vivos e reduzindo a manipulação da amostra. Seccionamento dos tecidos por meio de um vibratome é altamente preciso e gera homogeneaous secções, que, dependendo do objectivo do estudo, poderá, então, ser usados ​​com várias técnicas de coloração diferentes. Os métodos mais simples de visualizar lignina e outros compostos aromáticos empregar ultravioleta (UV). Excitação de moléculas aromáticas à base de luz UV é uma técnica antiga, mas ainda é uma das abordagens mais rápido para visualização de lignina. No entanto, a visualização UV na verdade não é ideal para a detecção de lignina porque a luz UV vão animar outros compostos aromáticos. A lignina é composta basicamente de três blocos de construção, as monolignóis (álcoois hidroxicinamil: álcool coniferil, álcool sinapyl e álcool p-cumaril) 1-3. Floroglucinol mancha pode proporcionar pistas para a extensão da cinnamaldehydes presentes no xilema, fibras e tecidos da traqueia 4. Floroglucinol é um bom indicador de cinnamaldehydes gerais e pode diferenciar entre cinnamaldehydes e outros aromáticos. Os monómeros de álcool sinapyl pode ser detectadae diferenciando-se pelo uso de Maule mancha. Azul de toluidina O é um corante policromático e, portanto, tem a capacidade de manchar os diferentes elementos da parede celular em diferentes cores 5,6. O principal uso do azul de toluidina O é detectar pectina e lignina 5,6. A vantagem do uso de azul de toluidina O é que muitos elementos da parede da célula pode ser visualizado num único passo. Ambos calcoflúor branco e vermelho congo são fáceis de trabalhar e pode ser usado para visualizar celulose. Calcofluor manchas brancas celulose, calose, e outros β-glucanas não-substituídos ou substituídos fracamente 6-9, ao passo que congo manchas vermelhas directamente para β-(1 → 4)-glucanos e em particular a celulose 10,11. O objetivo deste estudo é fornecer orientações simples para o uso das técnicas de coloração acima mencionados para obter imagens de alta qualidade a partir de A. thaliana hastes.

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			<td>EMD</td>
			<td>MERC2125</td>
			<td>CAS Number: 9012-36-6</td>
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			<td>Phloroglucinol</td>
			<td>Sigma</td>
			<td>P 3502</td>
			<td>1,3,5-trihydroxybenzene [CAS Number: 108-73-6]</td>
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			<td>Hydrochloric Acid</td>
			<td>EMD</td>
			<td>HX0603-75</td>
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			<td>EMD</td>
			<td>AX1303-6</td>
			<td>CAS Number: 1336-21-6</td>
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			<td>Sigma</td>
			<td>T3260</td>
			<td>Blutene chloride, Tolonium Chloride [CAS Number 92-31-9]&#160;</td>
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			<td>223468</td>
			<td>CAS Number 7722-64-7&#160;</td>
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			<td>KOPTEC</td>
			<td>V1401</td>
			<td>CAS Number: 64-17-5</td>
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			<td>Congo Red</td>
			<td>Sigma&#160;</td>
			<td>C6277</td>
			<td>Disodium 3,3&#39;-[[1,1&#39;-biphenyl]-4,4&#39;-diylbis(azo)]bis(4-aminonaphthalene 1-sulphonate) [CAS Number 573-58-0 ]</td>
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			<td>Stainless Steel Double Edge Blade (Personna Super)</td>
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			<td>NN-SD762S</td>
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			<td>Camera with CCD chip with no mechanical shutter&#160;</td>
			<td>Hamamatsu</td>
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			<td>MicroPublisher 5.0 RTV</td>
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			<td>Camera software&#160;</td>
			<td>&#160;Molecular Devices</td>
			<td>MetaMorph version 7.7.0.0</td>
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			<td>Imagining anaylsis&#160;</td>
			<td>Adobe&#160;</td>
			<td>Photoshop CS4</td>
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			<td>Micro Cover Glasses, Square, No.1</td>
			<td>VWR</td>
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histochemical staining of arabidopsis thaliana secondary cell wall elements

Arabidopsis thaliana is a model organism commonly used to understand and manipulate various cellular processes in plants, and it has been used extensively in the study of secondary cell wall formation. Secondary cell wall deposition occurs after the primary cell wall is laid down, a process carried out exclusively by specialized cells such as those forming vessel and fiber tissues. Most secondary cell walls are composed of cellulose (40&#8211;50%), hemicellulose (25&#8211;30%), and lignin (20&#8211;30%). Several mutations affecting secondary cell wall biosynthesis have been isolated, and the corresponding mutants may or may not exhibit obvious biochemical composition changes or visual phenotypes since these mutations could be masked by compensatory responses. Staining procedures have historically been used to show differences on a cellular basis. These methods are exclusively visual means of analysis; nevertheless their role in rapid and critical analysis is of great importance. Congo red and calcofluor white are stains used to detect polysaccharides, whereas M&#228;ule and phloroglucinol are commonly used to determine differences in lignin, and toluidine blue O is used to differentially stain polysaccharides and lignin. The seemingly simple techniques of sectioning, staining, and imaging can be a challenge for beginners. Starting with sample preparation using the A. thaliana model, this study details the protocols of a variety of staining methodologies that can be easily implemented for observation of cell and tissue organization in secondary cell walls of plants.

Stem Embedding e Seccionamento: A utilização do molde de plástico caseiro para incorporar os caules em 7% de agarose revelou-se fácil e rapidamente (Figura 1). As duas partes (A e B; Figura 1) do sistema de frasco incorporado torná-lo simples para liberar facilmente a haste incorporado em agarose como a agarose não se ater às partes dos frascos que são inertes, mantendo o sistema limpo. Os frascos podem ser reutilizados várias vezes durante anos. A conveniência de armaz...

Watch this Scientific Journal Video about Histochemical Staining of Arabidopsis thaliana Secondary Cell Wall Elements at JoVE.com

Histochemical Staining of Arabidopsis thaliana Secondary Cell Wall Elements

Plant cell wall composition varies between tissue types and can include lignin, cellulose, hemicelluloses, and pectin. Various staining techniques have been developed to visualize differences at the cell-type level. This paper is a compilation of commonly used cell wall staining techniques.

Coloração histoquímica de<em&gt; Arabidopsis thaliana</em&gt; Celular Secundária parede Elements

Arabidopsis thaliana is a model organism commonly used to understand and manipulate various cellular processes in plants, and it has been used extensively ...

histochemical-staining-arabidopsis-thaliana-secondary-cell-wall

Research

JoVE Journal

Biology

Histochemical Staining of Arabidopsis thaliana Secondary Cell Wall Elements

40.3K visualizações.  Joint Bioenergy Institute. Plant cell wall composition varies between tissue types and can include lignin, cellulose, hemicelluloses, and pectin. Various staining techniques have been developed to visualize differences at the cell-type level. This paper is a compilation of commonly used cell wall staining techniques.

Vídeo: Histochemical Staining of Arabidopsis thaliana Secondary Cell Wall Elements

Isolation of Protoplasts from Tissues of 14-day-old Seedlings of Arabidopsis thaliana

Protoplasts are plant cells that have had their cell walls enzymatically removed. Isolation of protoplasts from different plant tissues was first reported more than 40 years ago 1 and has since been adapted to study a variety of cellular processes, such as subcellular localization of proteins, isolation of intact organelles and targeted gene-inactivation by double stranded RNA interference (RNAi) 2-5. Most of the protoplast isolation protocols use leaf tissues of mature Arabidopsis (e.g. 35-day-old plants) 2-4. We modified existing protocols by employing 14-day-old Arabidopsis seedlings. In this procedure, one gram of 14-day-old seedlings yielded 5 106-107 protoplasts that remain intact at least 96 hours. The yield of protoplasts from seedlings is comparable with preparations from leaves of mature Arabidopsis, but instead of 35-36 days, isolation of protoplasts is completed in 15 days. This allows decreasing the time and growth chamber space that are required for isolating protoplasts when mature plants are used, and expedites the downstream studies that require intact protoplasts.

Isolation of Protoplasts from Tissues of 14-day-old Seedlings of Arabidopsis thaliana

This video shows a procedure for isolating intact protoplasts from tissues of 14-day-old seedlings of Arabidopsis. Given that the isolated protoplasts remain intact for at least 96h and are isolated from seedlings instead of one-month-old mature plants, this procedure expedites assays requiring intact protoplasts.

Isolamento de Protoplastos de tecidos de 14 dias de idade, mudas de Arabidopsis thaliana</em

Protoplasts are plant cells that have had their cell walls enzymatically removed. Isolation of protoplasts  from different plant tissues was first ...

Biologia

Investigating Tissue- and Organ-specific Phytochrome Responses using FACS-assisted Cell-type Specific Expression Profiling in Arabidopsis thaliana

Light mediates an array of developmental and adaptive processes throughout the life cycle of a plant. Plants utilize light-absorbing molecules called photoreceptors to sense and adapt to light. The red/far-red light-absorbing phytochrome photoreceptors have been studied extensively. Phytochromes exist as a family of proteins with distinct and overlapping functions in all higher plant systems in which they have been studied1. Phytochrome-mediated light responses, which range from seed germination through flowering and senescence, are often localized to specific plant tissues or organs2. Despite the discovery and elucidation of individual and redundant phytochrome functions through mutational analyses, conclusive reports on distinct sites of photoperception and the molecular mechanisms of localized pools of phytochromes that mediate spatial-specific phytochrome responses are limited. We designed experiments based on the hypotheses that specific sites of phytochrome photoperception regulate tissue- and organ-specific aspects of photomorphogenesis, and that localized phytochrome pools engage distinct subsets of downstream target genes in cell-to-cell signaling. We developed a biochemical approach to selectively reduce functional phytochromes in an organ- or tissue-specific manner within transgenic plants. Our studies are based on a bipartite enhancer-trap approach that results in transactivation of the expression of a gene under control of the Upstream Activation Sequence (UAS) element by the transcriptional activator GAL43. The biliverdin reductase (BVR) gene under the control of the UAS is silently maintained in the absence of GAL4 transactivation in the UAS-BVR parent4. Genetic crosses between a UAS-BVR transgenic line and a GAL4-GFP enhancer trap line result in specific expression of the BVR gene in cells marked by GFP expression4. BVR accumulation in Arabidopsis plants results in phytochrome chromophore deficiency in planta5-7. Thus, transgenic plants that we have produced exhibit GAL4-dependent activation of the BVR gene, resulting in the biochemical inactivation of phytochrome, as well as GAL4-dependent GFP expression. Photobiological and molecular genetic analyses of BVR transgenic lines are yielding insight into tissue- and organ-specific phytochrome-mediated responses that have been associated with corresponding sites of photoperception4, 7, 8. Fluorescence Activated Cell Sorting (FACS) of GFP-positive, enhancer-trap-induced BVR-expressing plant protoplasts coupled with cell-type-specific gene expression profiling through microarray analysis is being used to identify putative downstream target genes involved in mediating spatial-specific phytochrome responses. This research is expanding our understanding of sites of light perception, the mechanisms through which various tissues or organs cooperate in light-regulated plant growth and development, and advancing the molecular dissection of complex phytochrome-mediated cell-to-cell signaling cascades.

Investigating Tissue- and Organ-specific Phytochrome Responses using FACS-assisted Cell-type Specific Expression Profiling in Arabidopsis thaliana

The molecular basis of spatial-specific phytochrome responses is being investigated using transgenic plants that exhibit tissue- and organ-specific phytochrome deficiencies. The isolation of specific cells exhibiting induced phytochrome chromophore depletion by Fluorescence-Activated Cell Sorting followed by microarray analyses is being utilized to identify genes involved in spatial-specific phytochrome responses.

Investigando Tecido e órgãos específicos Responses Fitocromo usando FACS assistida Célula tipo Profiling expressão específica no Arabidopsis thaliana</em

Light mediates an array of developmental and adaptive processes throughout the life cycle of a plant. Plants utilize light-absorbing molecules called ...

Floral-dip Transformation of Arabidopsis thaliana to Examine pTSO2::&beta;-glucuronidase Reporter Gene Expression

The ability to introduce foreign genes into an organism is the foundation for modern biology and biotechnology. In the model flowering plant Arabidopsis thaliana, the floral-dip transformation method1-2 has replaced all previous methods because of its simplicity, efficiency, and low cost. Specifically, shoots of young flowering Arabidopsis plants are dipped in a solution of Agrobacterium tumefaciens carrying specific plasmid constructs. After dipping, the plants are returned to normal growth and yield seeds, a small percentage of which are transformed with the foreign gene and can be selected for on medium containing antibiotics. This floral-dip method significantly facilitated Arabidopsis research and contributed greatly to our understanding of plant gene function. In this study, we use the floral-dip method to transform a reporter gene, &beta;-glucuronidase (GUS), under the control of TSO2 promoter. TSO2, coding for the Ribonucleotide Reductase (RNR) small subunit3, is a cell cycle regulated gene essential for dNDP biosynthesis in the S-phase of the cell cycle. Examination of GUS expression in transgenic Arabidopsis seedlings shows that TSO2 is expressed in actively dividing tissues. The reported experimental method and materials can be easily adapted not only for research but also for education at high school and college levels.

Floral-dip Transformation of Arabidopsis thaliana to Examine pTSO2::&#946;-glucuronidase Reporter Gene Expression

This article illustrates the floral-dip method of Agrobacterium tumefaciens -mediated transformation of Arabidopsis thaliana. By introducing a cell-cycle regulated promoter-reporter, pTSO2::&beta;-glucuronidase (GUS), into Arabidopsis, we illustrates how one detects GUS reporter expression in transgenic seedlings.

Floral-dip Transformação de Arabidopsis thaliana Examine a PTSO2:: β-glucuronidase Expressão Gênica Reporter

The ability to introduce foreign genes into an organism is the foundation for modern biology and biotechnology. In the model flowering plant Arabidopsis ...

Arabidopsis thaliana Polar Glycerolipid Profiling by Thin Layer Chromatography (TLC) Coupled with Gas-Liquid Chromatography (GLC)

Biological membranes separate cells from the environment. From a single cell to multicellular plants and animals, glycerolipids, such as phosphatidylcholine or phosphatidylethanolamine, form bilayer membranes which act as both boundaries and interfaces for chemical exchange between cells and their surroundings. Unlike animals, plant cells have a special organelle for photosynthesis, the chloroplast. The intricate membrane system of the chloroplast contains unique glycerolipids, namely glycolipids lacking phosphorus: monogalactosyldiacylglycerol (MGDG), digalactosyldiacylglycerol (DGDG), sulfoquinovosyldiacylglycerol (SQDG)4. The roles of these lipids are beyond simply structural. These glycolipids and other glycerolipids were found in the crystal structures of photosystem I and II indicating the involvement of glycerolipids in photosynthesis8,11. During phosphate starvation, DGDG is transferred to extraplastidic membranes to compensate the loss of phospholipids9,12.
Much of our knowledge of the biosynthesis and function of these lipids has been derived from a combination of genetic and biochemical studies with Arabidopsis thaliana14. During these studies, a simple procedure for the analysis of polar lipids has been essential for the screening and analysis of lipid mutants and will be outlined in detail. A leaf lipid extract is first separated by thin layer chromatography (TLC) and glycerolipids are stained reversibly with iodine vapor. The individual lipids are scraped from the TLC plate and converted to fatty acyl methylesters (FAMEs), which are analyzed by gas-liquid chromatography coupled with flame ionization detection (FID-GLC) (Figure 1). This method has been proven to be a reliable tool for mutant screening. For example, the tgd1,2,3,4 endoplasmic reticulum-to-plastid lipid trafficking mutants were discovered based on the accumulation of an abnormal galactoglycerolipid: trigalactosyldiacylglycerol (TGDG) and a decrease in the relative amount of 18:3 (carbons : double bonds) fatty acyl groups in membrane lipids 3,13,18,20. This method is also applicable for determining enzymatic activities of proteins using lipids as substrate6.

Arabidopsis thaliana Polar Glycerolipid Profiling by Thin Layer Chromatography TLC Coupled with Gas-Liquid Chromatography GLC

Composition of polar lipid extracts and the fatty acid composition of individual glycerolipids are determined in a simple and robust lipid profiling experiment. For this purpose, glycerolipids are isolated by thin layer chromatography and subjected to transmethylation of their acyl groups. Fatty acyl methylesters are quantified by gas-liquid chromatography.

Arabidopsis thaliana Profiling Glycerolipid Polar por cromatografia em camada delgada (TLC) Juntamente com Cromatografia gás-líquido (GLC)

Biological membranes separate cells from the environment. From a single cell to multicellular plants and animals, glycerolipids, such as ...

Cell Specific Analysis of Arabidopsis Leaves Using Fluorescence Activated Cell Sorting

After initiation of the leaf primordium, biomass accumulation is controlled mainly by cell proliferation and expansion in the leaves1. However, the Arabidopsis leaf is a complex organ made up of many different cell types and several structures. At the same time, the growing leaf contains cells at different stages of development, with the cells furthest from the petiole being the first to stop expanding and undergo senescence1. Different cells within the leaf are therefore dividing, elongating or differentiating; active, stressed or dead; and/or responding to stimuli in sub-sets of their cellular type at any one time. This makes genomic study of the leaf challenging: for example when analyzing expression data from whole leaves, signals from genetic networks operating in distinct cellular response zones or cell types will be confounded, resulting in an inaccurate profile being generated.
To address this, several methods have been described which enable studies of cell specific gene expression. These include laser-capture microdissection (LCM)2 or GFP expressing plants used for protoplast generation and subsequent fluorescence activated cell sorting (FACS)3,4, the recently described INTACT system for nuclear precipitation5 and immunoprecipitation of polysomes6.
FACS has been successfully used for a number of studies, including showing that the cell identity and distance from the root tip had a significant effect on the expression profiles of a large number of genes3,7. FACS of GFP lines have also been used to demonstrate cell-specific transcriptional regulation during root nitrogen responses and lateral root development8, salt stress9 auxin distribution in the root10 and to create a gene expression map of the Arabidopsis shoot apical meristem11. Although FACS has previously been used to sort Arabidopsis leaf derived protoplasts based on autofluorescence12,13, so far the use of FACS on Arabidopsis lines expressing GFP in the leaves has been very limited4. In the following protocol we describe a method for obtaining Arabidopsis leaf protoplasts that are compatible with FACS while minimizing the impact of the protoplast generation regime. We demonstrate the method using the KC464 Arabidopsis line, which express GFP in the adaxial epidermis14, the KC274 line, which express GFP in the vascular tissue14 and the TP382 Arabidopsis line, which express a double GFP construct linked to a nuclear localization signal in the guard cells (data not shown; Figure 2). We are currently using this method to study both cell-type specific expression during development and stress, as well as heterogeneous cell populations at various stages of senescence.

Cell Specific Analysis of Arabidopsis Leaves Using Fluorescence Activated Cell Sorting

A method for producing Arabidopsis leaf protoplasts that are compatible with fluorescence activated cell sorting (FACS), allowing for studies of specific cell populations. This method is compatible with any Arabidopsis line that expresses GFP in a subset of cells.

Análise de célula específico<em&gt; Arabidopsis</em&gt; Folhas utilizando ordenação células activadas por fluorescência

After initiation of the leaf primordium, biomass accumulation is controlled mainly by cell proliferation and expansion in the leaves1. However, the ...

Glycan Profiling of Plant Cell Wall Polymers using Microarrays

Plant cell walls are complex matrixes of heterogeneous glycans which play an important role in the physiology and development of plants and provide the raw materials for human societies (e.g. wood, paper, textile and biofuel industries)1,2. However, understanding the biosynthesis and function of these components remains challenging.
Cell wall glycans are chemically and conformationally diverse due to the complexity of their building blocks, the glycosyl residues. These form linkages at multiple positions and differ in ring structure, isomeric or anomeric configuration, and in addition, are substituted with an array of non-sugar residues. Glycan composition varies in different cell and/or tissue types or even sub-domains of a single cell wall3. Furthermore, their composition is also modified during development1, or in response to environmental cues4.
In excess of 2,000 genes have Plant cell walls are complex matrixes of heterogeneous glycans been predicted to be involved in cell wall glycan biosynthesis and modification in Arabidopsis5. However, relatively few of the biosynthetic genes have been functionally characterized 4,5. Reverse genetics approaches are difficult because the genes are often differentially expressed, often at low levels, between cell types6. Also, mutant studies are often hindered by gene redundancy or compensatory mechanisms to ensure appropriate cell wall function is maintained7. Thus novel approaches are needed to rapidly characterise the diverse range of glycan structures and to facilitate functional genomics approaches to understanding cell wall biosynthesis and modification.
Monoclonal antibodies (mAbs)8,9 have emerged as an important tool for determining glycan structure and distribution in plants. These recognise distinct epitopes present within major classes of plant cell wall glycans, including pectins, xyloglucans, xylans, mannans, glucans and arabinogalactans. Recently their use has been extended to large-scale screening experiments to determine the relative abundance of glycans in a broad range of plant and tissue types simultaneously9,10,11.
Here we present a microarray-based glycan screening method called Comprehensive Microarray Polymer Profiling (CoMPP) (Figures 1 &amp; 2)10,11 that enables multiple samples (100 sec) to be screened using a miniaturised microarray platform with reduced reagent and sample volumes. The spot signals on the microarray can be formally quantified to give semi-quantitative data about glycan epitope occurrence. This approach is well suited to tracking glycan changes in complex biological systems12 and providing a global overview of cell wall composition particularly when prior knowledge of this is unavailable.

A technique called Comprehensive Microarray Polymer Profiling (CoMPP) for the characterisation of plant cell wall glycans is described. This method combines the specificity of monoclonal antibodies directed to defined glycan-epitopes with a miniature microarray analytical platform allowing screening of glycan occurrence in a broad range of biological contexts.

Profiling glicana de Polímeros da planta da parede celular usando Microarrays

Plant cell walls are complex matrixes of heterogeneous glycans which play an important role in the physiology and development of plants and provide the ...

Efficient and Rapid Isolation of Early-stage Embryos from Arabidopsis thaliana Seeds

In flowering plants, the embryo develops within a nourishing tissue - the endosperm - surrounded by the maternal seed integuments (or seed coat). As a consequence, the isolation of plant embryos at early stages (1 cell to globular stage) is technically challenging due to their relative inaccessibility. Efficient manual dissection at early stages is strongly impaired by the small size of young Arabidopsis seeds and the adhesiveness of the embryo to the surrounding tissues. Here, we describe a method that allows the efficient isolation of young Arabidopsis embryos, yielding up to 40 embryos in 1 hr to 4 hr, depending on the downstream application. Embryos are released into isolation buffer by slightly crushing 250-750 seeds with a plastic pestle in an Eppendorf tube. A glass microcapillary attached to either a standard laboratory pipette (via a rubber tube) or a hydraulically controlled microinjector is used to collect embryos from droplets placed on a multi-well slide on an inverted light microscope. The technical skills required are simple and easily transferable, and the basic setup does not require costly equipment. Collected embryos are suitable for a variety of downstream applications such as RT-PCR, RNA sequencing, DNA methylation analyses, fluorescence in situ hybridization (FISH), immunostaining, and reporter gene assays.

Efficient and Rapid Isolation of Early-stage Embryos from Arabidopsis thaliana Seeds

We report an efficient and simple method to isolate embryos at early stages of development from Arabidopsis thaliana seeds. Up to 40 embryos can be isolated in 1 hr to 4 hr, depending on the downstream application. The procedure is suitable for transcriptome, DNA methylation, reporter gene expression, immunostaining and fluorescence in situ hybridization analyses.

Isolamento eficiente e rápida de embriões em início de carreira a partir de<em&gt; Arabidopsis thaliana</em&gt; Sementes

In flowering plants, the embryo develops within a nourishing tissue - the endosperm - surrounded by the maternal seed integuments (or seed coat). As a ...

Metabolic Labeling and Membrane Fractionation for Comparative Proteomic Analysis of Arabidopsis thaliana Suspension Cell Cultures

Plasma membrane microdomains are features based on the physical properties of the lipid and sterol environment and have particular roles in signaling processes. Extracting sterol-enriched membrane microdomains from plant cells for proteomic analysis is a difficult task mainly due to multiple preparation steps and sources for contaminations from other cellular compartments. The plasma membrane constitutes only about 5-20% of all the membranes in a plant cell, and therefore isolation of highly purified plasma membrane fraction is challenging. A frequently used method involves aqueous two-phase partitioning in polyethylene glycol and dextran, which yields plasma membrane vesicles with a purity of 95% 1. Sterol-rich membrane microdomains within the plasma membrane are insoluble upon treatment with cold nonionic detergents at alkaline pH. This detergent-resistant membrane fraction can be separated from the bulk plasma membrane by ultracentrifugation in a sucrose gradient 2. Subsequently, proteins can be extracted from the low density band of the sucrose gradient by methanol/chloroform precipitation. Extracted protein will then be trypsin digested, desalted and finally analyzed by LC-MS/MS. Our extraction protocol for sterol-rich microdomains is optimized for the preparation of clean detergent-resistant membrane fractions from Arabidopsis thaliana cell cultures.
We use full metabolic labeling of Arabidopsis thaliana suspension cell cultures with K15NO3 as the only nitrogen source for quantitative comparative proteomic studies following biological treatment of interest 3. By mixing equal ratios of labeled and unlabeled cell cultures for joint protein extraction the influence of preparation steps on final quantitative result is kept at a minimum. Also loss of material during extraction will affect both control and treatment samples in the same way, and therefore the ratio of light and heave peptide will remain constant. In the proposed method either labeled or unlabeled cell culture undergoes a biological treatment, while the other serves as control 4.

Metabolic Labeling and Membrane Fractionation for Comparative Proteomic Analysis of Arabidopsis thaliana Suspension Cell Cultures

Here we describe a robust method for the fractionation of plant plasma membranes into detergent resistant and detergent soluble membranes based on a mixture of unlabeled and in vivo fully 15N labeled Arabidopsis thaliana cell cultures. The procedure is applied for comparative proteomic studies to understand signaling processes.

Metabólica Labeling e Membrana Fracionamento para Comparative Analysis proteômica de<em&gt; Arabidopsis thaliana</em&gt; Culturas suspensão de células

Plasma membrane microdomains are features based on the physical properties of the lipid and sterol environment and have particular roles in signaling ...

A Seed Coat Bedding Assay to Genetically Explore In Vitro How the Endosperm Controls Seed Germination in Arabidopsis thaliana

The Arabidopsis endosperm consists of a single cell layer surrounding the mature embryo and playing an essential role to prevent the germination of dormant seeds or that of nondormant seeds irradiated by a far red (FR) light pulse. In order to further gain insight into the molecular genetic mechanisms underlying the germination repressive activity exerted by the endosperm, a &#34;seed coat bedding&#34; assay (SCBA) was devised. The SCBA is a dissection procedure physically separating seed coats and embryos from seeds, which allows monitoring the growth of embryos on an underlying layer of seed coats. Remarkably, the SCBA reconstitutes the germination repressive activities of the seed coat in the context of seed dormancy and FR-dependent control of seed germination. Since the SCBA allows the combinatorial use of dormant, nondormant and genetically modified seed coat and embryonic materials, the genetic pathways controlling germination and specifically operating in the endosperm and embryo can be dissected. Here we detail the procedure to assemble a SCBA.

A Seed Coat Bedding Assay to Genetically Explore In Vitro How the Endosperm Controls Seed Germination in Arabidopsis thaliana

We present the procedure to assemble a seed coat bedding assay (SCBA) from Arabidopsis thaliana seeds. The SCBA was shown to be a powerful tool to explore genetically and in vitro how the endosperm controls seed germination in dormant seeds and in response to light cues. The SCBA is in principle applicable under any situation where the endosperm is suspected to influence embryonic growth.

A Brasão Cama Ensaio de Sementes para explorar Geneticamente<em&gt; In Vitro</em&gt; Como a germinação Controles do endosperma das sementes em<em&gt; Arabidopsis thaliana</em

The Arabidopsis endosperm consists of a single cell layer surrounding the mature embryo and playing an essential role to prevent the germination of ...

High Resolution Quantification of Crystalline Cellulose Accumulation in Arabidopsis Roots to Monitor Tissue-specific Cell Wall Modifications

Plant cells are surrounded by a cell wall, the composition of which determines their final size and shape. The cell wall is composed of a complex matrix containing polysaccharides that include cellulose microfibrils that form both crystalline structures and cellulose chains of amorphous organization. The orientation of the cellulose fibers and their concentrations dictate the mechanical properties of the cell. Several methods are used to determine the levels of crystalline cellulose, each bringing both advantages and limitations. Some can distinguish the proportion of crystalline regions within the total cellulose. However, they are limited to whole-organ analyses that are deficient in spatiotemporal information. Others relying on live imaging, are limited by the use of imprecise dyes. Here, we report a sensitive polarized light-based system for specific quantification of relative light retardance, representing crystalline cellulose accumulation in cross sections of Arabidopsis thaliana roots. In this method, the cellular resolution and anatomical data are maintained, enabling direct comparisons between the different tissues composing the growing root. This approach opens a new analytical dimension, shedding light on the link between cell wall composition, cellular behavior and whole-organ growth.

High Resolution Quantification of Crystalline Cellulose Accumulation in Arabidopsis Roots to Monitor Tissue-specific Cell Wall Modifications

Crystalline cellulose is an important constituent of the plant cell wall. However, its quantification at a cellular resolution is technically challenging. Here, we report the use of polarized light technology and root cross sections to obtain information of cell wall composition at a spatiotemporal resolution.

Quantificação de alta resolução Celulose cristalina Acumulação em<em&gt; Arabidopsis</em&gt; Raízes para monitorar celular específico do tecido da parede Modificações

Plant cells are surrounded by a cell wall, the composition of which determines their final size and shape. The cell wall is composed of a complex matrix ...

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