RESUMEN
In saline soils, high levels of sodium (Na+ ) and chloride (Cl- ) ions reduce root growth by inhibiting cell division and elongation, thereby impacting on crop yield. Soil salinity can lead to Na+ toxicity of plant cells, influencing the uptake and retention of other important ions [i.e. potassium (K+ )] required for growth. However, measuring and quantifying soluble ions in their native, cellular environment is inherently difficult. Technologies that allow in situ profiling of plant tissues are fundamental for our understanding of abiotic stress responses and the development of tolerant crops. Here, we employ laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) to quantify Na, K and other elements [calcium (Ca), magnesium (Mg), sulphur (S), phosphorus (P), iron (Fe)] at high spatial resolution in the root growth zone of two genotypes of barley (Hordeum vulgare) that differ in salt-tolerance, cv. Clipper (tolerant) and Sahara (sensitive). The data show that Na+ was excluded from the meristem and cell division zone, indicating that Na+ toxicity is not directly reducing cell division in the salt-sensitive genotype, Sahara. Interestingly, in both genotypes, K+ was strongly correlated with Na+ concentration, in response to salt stress. In addition, we also show important genetic differences and salt-specific changes in elemental composition in the root growth zone. These results show that LA-ICP-MS can be used for fine mapping of soluble ions (i.e. Na+ and K+ ) in plant tissues, providing insight into the link between Na+ toxicity and root growth responses to salt stress.
Asunto(s)
Hordeum/fisiología , Raíces de Plantas/fisiología , Plantas Tolerantes a la Sal/fisiología , Calcio/análisis , Hordeum/química , Hierro/análisis , Terapia por Láser/métodos , Magnesio/análisis , Meristema/química , Meristema/fisiología , Fósforo/análisis , Raíces de Plantas/química , Potasio/análisis , Tolerancia a la Sal , Plantas Tolerantes a la Sal/química , Sodio/análisis , Espectrofotometría Atómica , Azufre/análisisRESUMEN
The use of allelopathic compounds is an alternative for weeds control, since they present low toxicity when compared with the synthetic herbicides, that may cause several damages, as the contamination of the environment. Our objective was to determine the chemical composition and allelopathic properties of the essential oils of Psidium cattleianum, P. myrtoides, P. friedrichsthalianum, and P. gaudichaudianum on the germination and root growth of Lactuca sativa and Sorghum bicolor, and to evaluate their action on the cell cycle of root meristematic cells of L. sativa. The main compound found in all the studied species was (E)-caryophyllene (P. cattleianum-23.4 %; P. myrtoides-19.3%; P. friedrichsthalianum-24.6% and P. gaudichaudianum-17.0%). The different essential oils were tested at different concentrations on L. sativa and S. bicolor, reducing germination, germination speed index, and root and shoot growth of lettuce and sorghum seedlings. The cytotoxicity and aneugenic potential of these oils were evidenced by the reduction of the mitotic index and increase of the frequency of chromosomal alterations in L. sativa. The essential oils of the species of Psidium studied have potential to be used in weeds control.
Asunto(s)
Germinación/efectos de los fármacos , Herbicidas/farmacología , Lactuca/efectos de los fármacos , Meristema/química , Aceites Volátiles/química , Aceites de Plantas/farmacología , Psidium/química , Plantones/efectos de los fármacos , Sorghum/química , Alelopatía , Herbicidas/química , Lactuca/química , Fitoquímicos , Sesquiterpenos Policíclicos , Psidium/efectos de los fármacos , SesquiterpenosRESUMEN
The Bromeliaceae Puya chilensis Mol. is a native monocotyledonous food plant that can be found in central Chile. It is traditionally known as chagual. The tender basal part of the leaves, just starting from the meristem, are consumed as a salad. The aim of this work was to describe the phenolic content and composition of the meristem and leaves of chagual, as well as their antioxidant capacity and inhibitory activity against metabolic syndrome-associated enzymes. Samples of chagual, including two cultivated and three wild growing plants, were analyzed and compared for composition and bioactivity. From the phenolic enriched extract of the plant (PEE), 26 compounds were tentatively identified by HPLC-DAD-ESI-MSn, including 12 hydroxycinnamic acids and 14 flavonoids. The main compounds were identified as diferuloyl hexaric acid isomers and 5-p-Coumaroylquinic acid. The compounds were quantified in both meristem and leaves. The PEE content was up to ten times higher in the meristem than in the leaves, ranging from 0.18 to 124.08â¯mg/g PEE. The samples inhibited α-glucosidase, but did not show effect on α-amylase and pancreatic lipase. This is the first report on the polyphenol composition and bioactivity of the edible components of the chagual food plant.
Asunto(s)
Antioxidantes/análisis , Bromeliaceae/química , Meristema/química , Extractos Vegetales/química , Hojas de la Planta/química , Polifenoles/análisis , Antioxidantes/farmacología , Compuestos de Bifenilo , Chile , Ácidos Cumáricos/análisis , Flavonoides/análisis , Inhibidores de Glicósido Hidrolasas/análisis , Inhibidores de Glicósido Hidrolasas/farmacología , Picratos , Extractos Vegetales/farmacología , Ácido Quínico/análisis , alfa-Glucosidasas/efectos de los fármacosRESUMEN
BACKGROUND AND OBJECTIVE: There have been a number of reported drawbacks and efficacy issues regarding the use of bleaching agents in the plant industry. This study was conducted to determine the cytological effects of the bleaching agent (Quneex) on the plant cells and plant DNA using the Allium cepa assay. MATERIALS AND METHODS: It was subjected sixteen root meristems of A. cepa to different concentrations of the bleaching agent (0.1, 0.2, 0.3, 0.4 and 0.5%) with different periods of time (6, 12 and 24 h). Recovery was done for 6, 12 and 24 h after exposure. RESULTS: The mitotic index significantly decreased with time and also decreased with increase in the concentration of the bleaching agent. Abnormal chromosomal changes reflecting mutagenesis including stickiness, laggards, bridges, C-metaphase, star-metaphase, binucleation, polyploidy, disturbance and multinucleation were observed in the different concentrations and periods of time. After recovery, a slow increase in the mitotic index was observed. All treatments with or without recovery for 12 and 24 h resulted in reduction in the amount of DNA. CONCLUSION: Bleaching agents similar to Quneex containing sodium hypochlorite have mutagenic properties that can be potentially hazardous to the environment and also to humans. Thus, there is a need to regulate the use and disposal of such chemicals into the environment particularly to the sewers, to prevent contamination of potable water, plant and biodiverse aquatic animals.
Asunto(s)
Blanqueadores/farmacología , ADN de Plantas/efectos de los fármacos , Células Vegetales/efectos de los fármacos , Aberraciones Cromosómicas/efectos de los fármacos , Meristema/química , Mitosis/efectos de los fármacos , Índice Mitótico , Mutágenos/farmacología , Cebollas/química , Raíces de Plantas/efectos de los fármacosRESUMEN
Based on our long-standing experience with in vitro culture of Hypericum perforatum, a clonal multiplication system and vitrification-based cryopreservation protocols have been applied to several Hypericum species: H. humifusum L., H. annulatum Moris, H. tomentosum L., H. tetrapterum Fries, H. pulchrum L., and H. rumeliacum Boiss. The shoot tips were cryopreserved using a uniform procedure that includes pretreatment with abscisic acid (ABA), PVS3 cryoprotection, and direct immersion into the liquid nitrogen (LN). The freezing-tolerant Hypericum species were pre-exposed to the cold acclimation conditions performed by a 7-day exposure to 4 °C. The content of naphtodianthrones (hypericins) including hypericin, pseudohypericin, and their protoforms was quantified by HPLC. Ploidy of plants was determined by both flow cytometry of leaf tissue and chromosome counts of root tip meristematic cells. We have shown that the post-thaw recovery rate of the shoot tips, pretreated with 0.076 µM ABA for 7 days at room temperature, led to the post-cryogenic survival from 5 % in H. tomentosum to 21 % in H. annulatum. As compared to the untreated (control) plants, the content of hypericins in plants regenerated after cryopreservation remained unchanged or decreased in H. perforatum, H. humifusum, H. annulatum, H. tomentosum, H. tetrapterum, and H. rumeliacum. However, the pre-exposition of the freezing-tolerant H. perforatum to cold acclimation prior to excision of the shoot tips has improved the post-thaw recovery to 45 % and resulted in threefold increase of the total hypericin content.
Asunto(s)
Criopreservación/métodos , Hypericum/fisiología , Meristema/fisiología , Brotes de la Planta/fisiología , Aclimatación , Antracenos , Cromatografía Líquida de Alta Presión/métodos , Cromosomas de las Plantas/genética , Crioprotectores/metabolismo , Análisis Citogenético/métodos , Citometría de Flujo/métodos , Hypericum/química , Hypericum/genética , Meristema/química , Meristema/genética , Perileno/análogos & derivados , Perileno/análisis , Brotes de la Planta/química , Brotes de la Planta/genética , Ploidias , VitrificaciónRESUMEN
The allelopathic potential of leaf aqueous extract (LAE) of Calotropis procera on growth behavior, ultrastructural changes on Cassia sophera L., and cytological changes on Allium cepa L. was investigated. LAE at different concentrations (0.5, 1, 2, and 4 %) significantly reduced the root length, shoot length, and dry biomass of C. sophera. Besides, the ultrastructural changes (through scanning electron microscopy, SEM) induced in epidermal cells of 15-day-old seedlings of Cassia leaf were also noticed. The changes induced were shrinking and contraction of epidermal cells along with the formation of major grooves, canals, and cyst-like structures. The treated samples of epidermal cells no longer seem to be smooth as compared to control. LAE at different concentrations induces chromosomal aberrations and variation in shape of the interphase and prophase nucleus in A. cepa root tip cells when compared with control groups. The mitotic index in treated onion root tips decreased with increasing concentrations of the extracts. The most frequent aberrations were despiralization at prophase with the formation of micronuclei, sticky anaphase with bridges, sticky telophase, C-metaphase, etc. The results also show the induction of ghost cells, cells with membrane damage, and cells with heterochromatic nuclei by extract treatment. Upon HPLC analysis, nine phenolic acids (caffeic acid, gentisic acid, catechol, gallic acid, syringic acid, ellagic acid, resorcinol, p-coumaric acid, and p-hydroxy benzoic acid) were identified. Thus, the phenolic acids are mainly responsible for the allelopathic behavior of C. procera.
Asunto(s)
Calotropis/metabolismo , Cassia/crecimiento & desarrollo , Germinación/efectos de los fármacos , Meristema/química , Cebollas/crecimiento & desarrollo , Extractos Vegetales/farmacología , Hojas de la Planta/metabolismo , Alelopatía/efectos de los fármacos , Cassia/efectos de los fármacos , Hidroxibenzoatos/química , Meristema/citología , Índice Mitótico , Cebollas/efectos de los fármacos , Epidermis de la Planta/citología , Epidermis de la Planta/efectos de los fármacosRESUMEN
To study the toxic mechanisms of lead (Pb) in plants, the effects of Pb on the morphology and structure of the nucleolus in root tip meristematic cells of Allium cepa var. agrogarum L. were investigated. Fluorescence labeling, silver-stained indirect immunofluorescent microscopy and western blotting were used. Fluorescence labeling showed that Pb ions were localized in the meristematic cells and the uptake and accumulation of Pb increased with treatment time. At low concentrations of Pb (1-10 µM) there were persistent nucleoli in some cells during mitosis, and at high concentration (100 µM) many of the nucleolar organizing regions were localized on sticky chromosomes in metaphase and anaphase cells. Pb induced the release of particles containing argyrophilic proteins to be released from the nucleus into the cytoplasm. These proteins contained nucleophosmin and nucleolin. Pb also caused the extrusion of fibrillarin from the nucleus into the cytoplasm. Western blotting demonstrated the increased expression of these three major nucleolar proteins under Pb stress.
Asunto(s)
Nucléolo Celular/efectos de los fármacos , Plomo/toxicidad , Cebollas/crecimiento & desarrollo , Nucléolo Celular/química , Meristema/química , Meristema/citología , Meristema/efectos de los fármacos , Microscopía Confocal , Mitosis/efectos de los fármacos , Nucleoproteínas/química , Nucleoproteínas/metabolismo , Cebollas/efectos de los fármacos , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Raíces de Plantas/citología , Factores de TiempoRESUMEN
The defence responses of potato against Phytophthora infestans were studied using the highly resistant Sarpo Mira cultivar. The effects of plant integrity, meristems, and roots on the hypersensitive response (HR), plant resistance, and the regulation of PR genes were analysed. Sarpo Mira shoots and roots grafted with the susceptible Bintje cultivar as well as non-grafted different parts of Sarpo Mira plants were inoculated with P. infestans. The progress of the infection and the number of HR lesions were monitored, and the regulation of PR genes was compared in detached and attached leaves. Additionally, the antimicrobial activity of plant extracts was assessed. The presented data show that roots are needed to achieve full pathogen resistance, that the removal of meristems in detached leaves inhibits the formation of HR lesions, that PR genes are differentially regulated in detached leaves compared with leaves of whole plants, and that antimicrobial compounds accumulate in leaves and roots of Sarpo Mira plants challenged with P. infestans. While meristems are necessary for the formation of HR lesions, the roots of Sarpo Mira plants participate in the production of defence-associated compounds that increase systemic resistance. Based on the literature and on the presented results, a model is proposed for mechanisms involved in Sarpo Mira resistance that may apply to other resistant potato cultivars.
Asunto(s)
Antiinfecciosos/farmacología , Regulación de la Expresión Génica de las Plantas/genética , Phytophthora infestans/patogenicidad , Enfermedades de las Plantas/inmunología , Extractos Vegetales/farmacología , Solanum tuberosum/inmunología , Antiinfecciosos/química , Resistencia a la Enfermedad , Meristema/química , Meristema/genética , Meristema/inmunología , Meristema/parasitología , Modelos Biológicos , Enfermedades de las Plantas/parasitología , Extractos Vegetales/química , Hojas de la Planta/química , Hojas de la Planta/genética , Hojas de la Planta/inmunología , Hojas de la Planta/parasitología , Proteínas de Plantas/genética , Raíces de Plantas/química , Raíces de Plantas/genética , Raíces de Plantas/inmunología , Raíces de Plantas/parasitología , Brotes de la Planta/química , Brotes de la Planta/genética , Brotes de la Planta/inmunología , Brotes de la Planta/parasitología , Transducción de Señal , Solanum tuberosum/química , Solanum tuberosum/genética , Solanum tuberosum/parasitologíaRESUMEN
The antimutagenic activities of the oils obtained from leaves and fruits of Fagus orientalis have been shown in experiments with spontaneous and mutagen- and ageing-induced variability. The aberrations of chromosomes in the meristematic cells of the Allium cepa L., Vicia faba L., Triticum aestivum L., and marrow cells of Vistar rats as well as Arabidopsis thaliana gene mutations have been mobilized as experimental tests.
Asunto(s)
Antimutagênicos/farmacología , Arabidopsis/efectos de los fármacos , Médula Ósea/metabolismo , Fagus/química , Meristema/efectos de los fármacos , Aceites/farmacología , Cebollas/efectos de los fármacos , Triticum/efectos de los fármacos , Vicia faba/efectos de los fármacos , Animales , Antimutagênicos/química , Arabidopsis/química , Arabidopsis/genética , Médula Ósea/química , Médula Ósea/efectos de los fármacos , Clorofila/análisis , Clorofila/química , Aberraciones Cromosómicas/efectos de los fármacos , Cromosomas/efectos de los fármacos , Frutas/química , Meristema/química , Meristema/genética , Metilnitrosourea/efectos adversos , Mutágenos/efectos adversos , Nitrosoguanidinas/efectos adversos , Aceites/química , Cebollas/química , Cebollas/genética , Extractos Vegetales/química , Extractos Vegetales/farmacología , Hojas de la Planta/química , Ratas , Ratas Wistar , Triticum/química , Triticum/genética , Vicia faba/química , Vicia faba/genéticaRESUMEN
We performed mass spectrometric imaging (MSI) to localize ginsenosides (Rb(1), Rb(2) or Rc, and Rf) in cross-sections of the Panax ginseng root at a resolution of 100 microm using matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). Tandem mass spectrometry (MS/MS) of alkali metal-adducted ginsenoside ions revealed structural information of the corresponding saccharides and aglycone. MALDI-MSI confirmed that ginsenosides were located more in the cortex and the periderm than that in the medulla of a lateral root. In addition, it revealed that localization of ginsenosides in a root tip (diameter, 2.7 mm) is higher than that in the center of the root (diameter, 7.3 mm). A quantitative difference was detected between localizations of protopanaxadiol-type ginsenoside (Rb(1), Rb(2), or Rc) and protopanaxatriol-type ginsenoside (Rf) in the root. This imaging approach is a promising technique for rapid evaluation and identification of medicinal saponins in plant tissues.
Asunto(s)
Ginsenósidos/análisis , Panax/química , Raíces de Plantas/química , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Ginsenósidos/química , Meristema/anatomía & histología , Meristema/química , Estructura Molecular , Panax/anatomía & histología , Raíces de Plantas/anatomía & histología , Xilema/anatomía & histología , Xilema/químicaRESUMEN
Elucidation of the molecular mechanisms determining the formation of various tissues and organs is one of the central problems of cell biology. High-resolution NMR spectroscopy was applied for the analysis of the metabolites produced at the various areas of the apical part of the onion Allium cepa roots. To this end, three samples were extracted from the root apex (the root cap, the meristem region and the cell elongation zone). These samples were noticeably different in the number of mitoses and the sets of metabolites. Furthermore, the complete stasis of the plant roots and tops growth was registered in heavy water. Comparison of the morphological and NMR data revealed their perfect agreement with the cellular processes occurring in the root apex. The root cap sample was characterized by the greatest mitotic activity reflected in the great variability of the chemical compounds extracted from this area, the high level of energy consumption, and the increased synthesis of the phosphocholines needed for the cell fission. Sample containing the cell elongation zone possessed the high sugar content, which is required for the cell-wall growth. Therefore, our data show that high-resolution NMR spectroscopy can be used for the identification of chemical compounds in the various regions of the onion root apical area.
Asunto(s)
Espectroscopía de Resonancia Magnética/métodos , Cebollas/metabolismo , Óxido de Deuterio/metabolismo , Meristema/química , Meristema/metabolismo , Cebollas/anatomía & histología , Cebollas/química , Cebollas/crecimiento & desarrollo , Raíces de Plantas/anatomía & histología , Raíces de Plantas/química , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismoRESUMEN
Fractionation and extraction of nuclear proteins are techniques intended to facilitate dedicated plant proteomic studies. These techniques rely on subcellular fractionation, which makes it possible to define and characterize the proteome of a subcellular organelle, in this case the cell nucleus. Nuclear protein fractionation is proposed as a method to be carried out according to the solubility of proteins in buffers of increasing ionic strength. This physical criterion, accompanied in some steps by the use of additional reagents, such as detergents or enzymes, produces fractions that have been demonstrated to have functional significance. The proposed procedure yields five fractions, the first of them containing proteins associated with the nuclear envelope and remnants of the cytoskeleton. The second fraction, which is soluble at low ionic strength, contains ribonucleoproteins active in nuclear RNA metabolism. After increasing ionic strength and digesting with DNase, the result is the chromatin fraction. Finally, the fourth and fifth fractions correspond to the nuclear matrix and are obtained, respectively, by solubilization in high salt concentration and in the form of the residual pellet, which is only soluble in 7 M urea under sonication. This procedure offers a wide range of applicability, even in the cases in which the genome of the particular species investigated is not sequenced. In general, the functional criteria driving the extraction method described here will make this method capable of generating valuable and useful information.
Asunto(s)
Meristema/química , Proteínas Nucleares/aislamiento & purificación , Proteínas de Plantas/aislamiento & purificación , Raíces de Plantas/química , Proteómica/métodos , Fraccionamiento Celular/métodos , Núcleo Celular/química , Electroforesis en Gel Bidimensional , Electroforesis en Gel de Poliacrilamida , Proteínas Nucleares/química , Cebollas/química , Proteínas de Plantas/química , Raíces de Plantas/citología , SolucionesRESUMEN
Remorins form a superfamily of plant-specific plasma membrane/lipid-raft-associated proteins of unknown structure and function. Using specific antibodies, we localized tomato remorin 1 to apical tissues, leaf primordia and vascular traces. The deduced remorin protein sequence contains a predicted coiled coil-domain, suggesting its participation in protein-protein interactions. Circular dichroism revealed that recombinant potato remorin contains an alpha-helical region that forms a functional coiled-coil domain. Electron microscopy of purified preparations of four different recombinant remorins, one from potato, two divergent isologs from tomato, and one from Arabidopsis thaliana , demonstrated that the proteins form highly similar filamentous structures. The diameters of the negatively-stained filaments ranged from 4.6-7.4 nm for potato remorin 1, 4.3-6.2 nm for tomato remorin 1, 5.7-7.5 nm for tomato remorin 2, and 5.7-8.0 nm for Arabidopsis Dbp. Highly polymerized remorin 1 was detected in glutaraldehyde-crosslinked tomato plasma membrane preparations and a population of the protein was immunolocalized in tomato root tips to structures associated with discrete regions of the plasma membrane.
Asunto(s)
Proteínas Portadoras/análisis , Meristema/química , Fosfoproteínas/análisis , Proteínas de Plantas/análisis , Plantas/química , Secuencia de Aminoácidos , Proteínas Portadoras/genética , Proteínas Portadoras/ultraestructura , Dicroismo Circular , Immunoblotting , Solanum lycopersicum/química , Solanum lycopersicum/genética , Proteínas de la Membrana/análisis , Proteínas de la Membrana/genética , Meristema/genética , Microscopía Confocal , Microscopía Electrónica , Datos de Secuencia Molecular , Peso Molecular , Oligopéptidos/análisis , Oligopéptidos/genética , Fosfoproteínas/genética , Fosfoproteínas/ultraestructura , Proteínas de Plantas/genética , Proteínas de Plantas/ultraestructura , Raíces de Plantas/química , Raíces de Plantas/genética , Brotes de la Planta/química , Brotes de la Planta/genética , Plantas/embriología , Plantas/genética , Proteínas Recombinantes/análisis , Solanum tuberosum/química , Solanum tuberosum/genéticaRESUMEN
The aneuploidy of Gossypium hirsutum L. (upland cotton) aneusomatics were obtained by induced parthenogenesis. These aneuploids could grow and set seeds normally. In the process of meiosis there appeared large quantities of heteromorphic pairs and multivalent chromosomes and many cases of cytomixis and multisperm fertilization occurred. The aneuploids produced offsprings through sexual propagation. We explored penetratingly the questions how and why these aneuploids could survive. Through this research, we found that the upland cotton possessed an immense latent capacity to adapt to adverse environments. More importantly, in the case of the upland cotton, we discovered that the genetic pattern of the polyploid differs in some respects from that of the diploid.
Asunto(s)
Aneuploidia , Cromosomas de las Plantas/genética , Diploidia , Gossypium/genética , Partenogénesis/genética , Poliploidía , Flores/química , Meiosis/genética , Meristema/química , Polen/genéticaRESUMEN
The POTM1-1 gene is abundantly expressed in both vegetative and reproductive organs of potato. We performed in situ hybridization and RNA blotting analysis to investigate the patterns of POTM1-1 gene expression in the flower development and the early tuber development. In the early flowers, POTM1-1 transcripts were accumulated abundantly in the developing reproductive organs, including the placentae of carpels and the pollen sacs of stamens. In contrast, the pattern of POTM1-1 distribution during late flower development was different from that of the early flower development. The POTM1-1 transcripts were abundant in the sepals and petals of late flowers, but were minimally expressed in the stamens and carpel. In the shoot apical meristem of the vegetative organs, transcripts were distributed throughout meristem domes, young leaves, and developing vascular cambium. In the early tuberization, the transcripts were widely distributed in the swollen tips of the stolons. Taken together, the results suggest that POTM1-1 gene expression is temporally and spatially regulated in active growing tissues of both vegetative and floral organs with specific distribution patterns dependent upon the developmental stages of the tissue.
Asunto(s)
Flores/química , Proteínas de Dominio MADS/genética , Meristema/química , Hojas de la Planta/química , Proteínas de Plantas/genética , Brotes de la Planta/química , ARN Mensajero/análisis , ARN de Planta/análisis , Solanum tuberosum/genética , Regulación del Desarrollo de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Hibridación in Situ , Especificidad de Órganos , Solanum tuberosum/crecimiento & desarrollo , Solanum tuberosum/metabolismo , Solanum tuberosum/ultraestructura , Transcripción GenéticaRESUMEN
A successful protocol for meristem tip culture to eliminate carnation latent virus from carnation cv. scania has been described . The virus was found to be mechanically transmissible to Chenopodium quinoa, C. amaranticolor, Dianthus barbatus and Saponaria vaccaria. Murashige and Skoog'smedium (MS) supplemented with NAA (1.0 microM) and Kn (20.0 microM) proved best for meristem establishment and microshoots were rooted in MS medium supplemented with IBA (5.0 microM). Meristems measuring 0.1 and-0.2 mm yielded virus free plants and larger meristems were not effective.
Asunto(s)
Adenina/análogos & derivados , Carlavirus/efectos de los fármacos , Dianthus/química , Dianthus/virología , Meristema/metabolismo , Enfermedades de las Plantas/virología , Hojas de la Planta/química , Adenina/metabolismo , Fosfatasa Alcalina/metabolismo , Carlavirus/crecimiento & desarrollo , Ensayo de Inmunoadsorción Enzimática , Cinetina , Meristema/química , Hojas de la Planta/virología , Brotes de la Planta/química , Brotes de la Planta/virología , Pruebas SerológicasRESUMEN
The cytotoxic activity of two pentacyclic triterpenoids (ursolic acid and alpha-amyrine) isolated from the methanolic extract of the aerial parts from Erica andevalensis, whose structures have been established on the basis of spectroscopic and chemical evidence, has been assessed against three human cancer cell lines, TK-10 (renal adenocarcinoma), MCF-7 (breast adenocarcinoma) and UACC-62 (melanoma), recommended by NCI (National Cancer Institute) and we also evaluated the antimitotic effect in root meristematic cells of Allium cepa. Ursolic acid was found to possess the highest cytotoxic activity.
Asunto(s)
Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/toxicidad , Plantas Medicinales/química , Triterpenos/toxicidad , Adenocarcinoma , Antineoplásicos Fitogénicos/aislamiento & purificación , Neoplasias de la Mama , Supervivencia Celular/efectos de los fármacos , Femenino , Humanos , Neoplasias Renales , Medicina Tradicional , Melanoma , Meristema/química , Meristema/citología , Estructura Molecular , España , Triterpenos/química , Triterpenos/aislamiento & purificación , Células Tumorales CultivadasRESUMEN
Expressed sequence tag (EST) analysis was conducted for young flower buds of radish plants. Among a total of 66 ESTs examined, 40 showed a significant similarity to previously identified genes. Twenty-eight ESTs were similar to proteins identified in other plants, 11 were similar to eukaryotic proteins other than plants, and one was similar to a prokaryotic protein. Four clones were selected for further studies. EST clone 81, which showed a homology to germin-like proteins was expressed more abundantly in leaves and roots as compared to flower buds. Clone 105 was highly homologous to the translation inhibitor protein and was expressed in all three organs, but the expression level was higher in flower buds and roots. Another EST clone, 133, which shared a significant similarity with the Ran-binding protein, hybridized to two different size transcripts that were detectable only in flower buds. Clone 39 was a homolog of CONSTANS, which is a gene involved in controlling the flowering time in Arabidopsis. The cDNA clone of EST clone 39 containing the entire open reading frame was obtained and designated as RsCOL1 (Raphanus sativus CONSTANS LIKE 1). It was 1049 bp long and contained an open reading frame of 307 amino acid residues (calculated molecular mass = 33.1 kDa). The RsCOL1 protein contained two putative zinc finger motifs in the amino terminal region which were 59% identical to the corresponding region of the Arabidopsis CO protein. The radish protein also contained a predicted nuclear localization domain in the carboxyl terminal region which was 87% identical to the corresponding region of CO. DNA blot analysis revealed that the radish genome contained several genes similar to RsCOL1. RNA blot analysis showed that RsCOL1 was strongly expressed in flower buds at the early bolting stage, and the expression level declined as the flower bud matured. The transcript was also detectable in leaves and roots. In mature flowers, the RsCOL1 transcript was present primarily in carpels.
Asunto(s)
Proteínas de Arabidopsis , Proteínas de Unión al ADN/genética , Etiquetas de Secuencia Expresada , Genes de Plantas/genética , Factores de Transcripción/genética , Verduras/genética , Secuencia de Aminoácidos , Secuencia de Bases , ADN Complementario/química , ADN Complementario/genética , Regulación del Desarrollo de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Meristema/química , Meristema/genética , Datos de Secuencia Molecular , Hojas de la Planta/química , Proteínas de Plantas/genética , Raíces de Plantas/química , ARN/genética , ARN/metabolismo , Alineación de Secuencia , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Distribución Tisular , Verduras/químicaRESUMEN
Transient expression and stable integration and expression of transgenes were observed in the tissues and offspring of certain leguminous plants after electroporation of DNA into intact nodal meristems in planta. The method described in this article thus allows the study of transgene expression in tissues differentiating from meristematic cells present in the treated buds. In addition, transgenic plants can be recovered in the offspring of electroporated individuals. Therefore, this technique allows the production of transgenic leguminous plants without the need for in vitro tissue culture, often a major hurdle with this family.
Asunto(s)
Electroporación/métodos , Técnicas de Transferencia de Gen , Meristema/genética , Plantas Modificadas Genéticamente/genética , Southern Blotting , ADN/química , Electrofisiología , Fabaceae/genética , Regulación de la Expresión Génica de las Plantas , Genes Reporteros , Glucuronidasa/genética , Meristema/química , Conformación de Ácido Nucleico , Pisum sativum/genética , Fosfatidiletanolaminas/química , Plantas Medicinales , Plásmidos , Glycine max/genética , Transformación GenéticaRESUMEN
A 834 bp cDNA encoding calmodulin (CaM) has been isolated from Brassica juncea. On Northern analysis this cDNA hybridises this cDNA to mRNAs of about 0.9 kb in leaf, silique and peduncle. Genomic Southern analysis indicates the presence of a CaM multigene family in Brassica juncea. Comparison of the predicted amino acid sequence of Brassica CaM with that of Arabidopsis CaM ACaM-2 and ACaM-3 showed 100% homology, which is not unusual, since both plants belong to the family Cruciferae. In situ hybridisation studies on Brassica seedlings using a digoxigenin-labelled RNA probe showed that high levels of CaM mRNA were detected in the leaf primordia and the shoot apical meristem, and to a lesser degree, in the zone of root elongation of the root tip. The occurrence of a higher rate of cell division and growth in these regions than its surrounding tissue may possibly be related to higher levels of CaM mRNA.