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Intercropping can favour the yield of the main crop. However, because of the potential competition among woody crops, this system is rarely used by farmers. To increase knowledge about the intercropping system, we have explored three different combinations of alley cropping in rainfed olive groves compared to conventional management (CP): (i) Crocus sativus (D-S); (ii) Vicia sativa/Avena sativa in annual rotation (D-O); and (iii) Lavandula x intermedia (D-L). Different soil chemical properties were analyzed to evaluate the effects of alley cropping, while 16S rRNA amplification and enzymatic activities were determined to study the changes that occurred in soil microbial communities and activity. In addition, the influence of intercropping on the potential functionality of the soil microbial community was measured. Data revealed that the intercropping systems highly affected the microbial community and soil properties. The D-S cropping system increased soil total organic carbon and total nitrogen that were correlated with the bacterial community, indicating that both parameters were the main drivers shaping the structure of the bacterial community. The D-S soil cropping system had significantly higher relative abundances of the phyla Bacteroidetes, Proteobacteria, and Patescibacteria compared to the other systems and the genera Adhaeribacter, Arthrobacter, Rubellimicrobium, and Ramlibacter, related to C and N functions. D-S soil was also related to the highest relative abundances of Pseudoarthrobacter and Haliangium, associated with the plant growth-promoting effect, antifungal activity, and a potential P solubilizer. A potentially increase of C fixation and N fixation in soils was also observed in the D-S cropping system. These positive changes were related to the cessation of tillage and the development of a spontaneous cover crop, which increased soil protection. Thus, management practices that contribute to increasing soil cover should be encouraged to improve soil functionality.
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Crocus , Olea , Suelo/química , Olea/genética , Crocus/genética , ARN Ribosómico 16S/genética , Bacterias/genética , Productos Agrícolas , Microbiología del SueloRESUMEN
BACKGROUND: Cowpea (Vigna unguiculata) is an important source of protein supply for animal and human nutrition. The major storage globulins VICILIN and LEGUMIN (LEG) are synthesized from several genes including LEGA, LEGB, LEGJ and CVC (CONVICILIN). The current hypothesis is that the plant circadian core clock genes are conserved in a wide array of species and that primary metabolism is to a large extent controlled by the plant circadian clock. Our aim was to investigate a possible link between gene expression of storage proteins and the circadian clock. RESULTS: We identified cowpea orthologues of the core clock genes VunLHY, VunTOC1, VunGI and VunELF3, the protein storage genes VunLEG, VunLEGJ, and VunCVC as well as nine candidate reference genes used in RT-PCR. ELONGATION FACTOR 1-A (ELF1A) resulted the most suitable reference gene. The clock genes VunELF3, VunGI, VunTOC1 and VunLHY showed a rhythmic expression profile in leaves with a typical evening/night and morning/midday phased expression. The diel patterns were not completely robust and only VungGI and VungELF3 retained a rhythmic pattern under free running conditions of darkness. Under field conditions, rhythmicity and phasing apparently faded during early pod and seed development and was regained in ripening pods for VunTOC1 and VunLHY. Mature seeds showed a rhythmic expression of VunGI resembling leaf tissue under controlled growth chamber conditions. Comparing time windows during developmental stages we found that VunCVC and VunLEG were significantly down regulated during the night in mature pods as compared to intermediate ripe pods, while changes in seeds were non-significant due to high variance. The rhythmic expression under field conditions was lost under growth chamber conditions. CONCLUSIONS: The core clock gene network is conserved in cowpea leaves showing a robust diel expression pattern except VunELF3 under growth chamber conditions. There appears to be a clock transcriptional reprogramming in pods and seeds compared to leaves. Storage protein deposition may be circadian regulated under field conditions but the strong environmental signals are not met under artificial growth conditions. Diel expression pattern in field conditions may result in better usage of energy for protein storage.
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Relojes Circadianos/fisiología , Hojas de la Planta/metabolismo , Hojas de la Planta/fisiología , Proteínas de Plantas/metabolismo , Semillas/metabolismo , Semillas/fisiología , Vigna/metabolismo , Vigna/fisiología , Relojes Circadianos/genética , Regulación de la Expresión Génica de las Plantas/genética , Regulación de la Expresión Génica de las Plantas/fisiología , Proteínas de Plantas/genéticaRESUMEN
BACKGROUND: Cowpea (Vigna unguiculata L. Walp) is an important legume crop due to its high protein content, adaptation to heat and drought and capacity to fix nitrogen. Europe has a deficit of cowpea production. Knowledge of genetic diversity among cowpea landraces is important for the preservation of local varieties and is the basis to obtain improved varieties. The aims of this study were to explore diversity and the genetic structure of a set of Iberian Peninsula cowpea accessions in comparison to a worldwide collection and to infer possible dispersion routes of cultivated cowpea. RESULTS: The Illumina Cowpea iSelect Consortium Array containing 51,128 SNPs was used to genotype 96 cowpea accessions including 43 landraces and cultivars from the Iberian Peninsula, and 53 landraces collected worldwide. Four subpopulations were identified. Most Iberian Peninsula accessions clustered together with those from other southern European and northern African countries. Only one accession belonged to another subpopulation, while two accessions were 'admixed'. A lower genetic diversity level was found in the Iberian Peninsula accessions compared to worldwide cowpeas. CONCLUSIONS: The genetic analyses performed in this study brought some insights into worldwide genetic diversity and structure and possible dispersion routes of cultivated cowpea. Also, it provided an in-depth analysis of genetic diversity in Iberian Peninsula cowpeas that will help guide crossing strategies in breeding programs.
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Polimorfismo de Nucleótido Simple , Vigna/genética , Marcadores Genéticos , Técnicas de Genotipaje , Vigna/clasificaciónRESUMEN
Phenomics is a technology-driven approach with promising future to obtain unbiased data of biological systems. Image acquisition is relatively simple. However data handling and analysis are not as developed compared to the sampling capacities. We present a system based on machine learning (ML) algorithms and computer vision intended to solve the automatic phenotype data analysis in plant material. We developed a growth-chamber able to accommodate species of various sizes. Night image acquisition requires near infrared lightning. For the ML process, we tested three different algorithms: k-nearest neighbour (kNN), Naive Bayes Classifier (NBC), and Support Vector Machine. Each ML algorithm was executed with different kernel functions and they were trained with raw data and two types of data normalisation. Different metrics were computed to determine the optimal configuration of the machine learning algorithms. We obtained a performance of 99.31% in kNN for RGB images and a 99.34% in SVM for NIR. Our results show that ML techniques can speed up phenomic data analysis. Furthermore, both RGB and NIR images can be segmented successfully but may require different ML algorithms for segmentation.
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Inteligencia Artificial , Fenotipo , Máquina de Vectores de Soporte , Algoritmos , Teorema de Bayes , PlantasRESUMEN
Unbiased identification of organisms by PCR reactions using universal primers followed by DNA sequencing assumes positive amplification. We used six universal loci spanning 48 plant species and quantified the bias at each step of the identification process from end point PCR to next-generation sequencing. End point amplification was significantly different for single loci and between species. Quantitative PCR revealed that Cq threshold for various loci, even within a single DNA extraction, showed 2,000-fold differences in DNA quantity after amplification. Next-generation sequencing (NGS) experiments in nine species showed significant biases towards species and specific loci using adaptor-specific primers. NGS sequencing bias may be predicted to some extent by the Cq values of qPCR amplification.
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Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Plantas/genética , Reacción en Cadena de la Polimerasa/métodosRESUMEN
The gene AINTEGUMENTA (AtANT) is an APETALA2 transcription factor in Arabidopsis activating growth downstream of auxin signalling. Lateral organ size is positively correlated with ANT expression in Arabidopsis. We tested the use of AtANT as a tool to modify floral size in two different plants used as model organisms and ornamental crops, Petunia × hybrida and Antirrhinum majus. Petunia plants expressing PhANT RNAi showed a decrease in PhANT expression correlated with smaller petal limbs. In contrast Petunia plants overexpressing AtANT had larger petal limbs. Petal tube length was less affected in down-regulation of PhANT or overexpression of AtANT. Overexpression of AtANT in Antirrhinum caused increased flower size via increased petal limb width and tube length. Down-regulation of PhANT showed an effect on cell size while overexpression of AtANT in Petunia and Antirrhinum caused significant increases in cell expansion that could explain the differences in floral organ size. The endogenous expression levels of PhANT and AmANT tended to be higher in the limb than in the tube in both Antirrhinum and Petunia. AtANT overexpression caused significant AmANT up-regulation in Antirrhinum limbs but not of PhANT in Petunia, indicating differences in the regulatory network. The differential effect of AtANT on limb and tube in Petunia and Antirrhinum correspond to phenotypic differences observed in natural variation in the corresponding genus indicating a relation between the phenotypic space of a genus and the effect of modified ANT levels, validating ANT as a gene to modify floral size.
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Antirrhinum/genética , Proteínas de Arabidopsis/genética , Flores/genética , Regulación de la Expresión Génica de las Plantas , Petunia/genética , Factores de Transcripción/genética , Antirrhinum/anatomía & histología , Antirrhinum/crecimiento & desarrollo , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulación hacia Abajo , Flores/anatomía & histología , Flores/crecimiento & desarrollo , Expresión Génica , Petunia/anatomía & histología , Petunia/crecimiento & desarrollo , Fenotipo , Filogenia , Plantas Modificadas Genéticamente , Interferencia de ARN , Factores de Transcripción/metabolismo , Regulación hacia ArribaRESUMEN
The transcriptional network topology of B function in Antirrhinum, required for petal and stamen development, is thought to rely on initial activation of transcription of DEFICIENS (DEF) and GLOBOSA (GLO), followed by a positive autoregulatory loop maintaining gene expression levels. Here, we show that the mutant compacta (co), whose vegetative growth and petal size are affected, plays a role in B function. Late events in petal morphogenesis such as development of conical cell area and scent emissions were reduced in co and defâ(nicotianoides) (defâ(nic) ), and absent in co defâ(nic) double mutants, suggesting a role for CO in petal identity. Expression of DEF was down-regulated in co but surprisingly GLO was not affected. We investigated the levels of DEF and GLO at late stages of petal development in the co, defâ(nic) and glo-1 mutants, and established a reliable transformation protocol that yielded RNAi-DEF lines. We show that the threshold levels of DEF or GLO required to obtain petal tissue are approximately 11% of wild-type. The relationship between DEF and GLO transcripts is not equal or constant and changes during development. Furthermore, down-regulation of DEF or GLO does not cause parallel down-regulation of the partner. Our results demonstrate that, at late stages of petal development, the B function transcriptional network topology is not based on positive autoregulation, and has additional components of transcriptional maintenance. Our results suggest changes in network topology that may allow changes in protein complexes that would explain the fact that not all petal traits appear early in development.
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Antirrhinum/genética , Flores/genética , Regulación del Desarrollo de la Expresión Génica/genética , Aceites Volátiles/metabolismo , Proteínas de Plantas/genética , Monoterpenos Acíclicos , Alquenos/análisis , Alquenos/metabolismo , Antirrhinum/anatomía & histología , Antirrhinum/crecimiento & desarrollo , Antirrhinum/metabolismo , Benzoatos/análisis , Benzoatos/metabolismo , Proteína DEFICIENS/genética , Proteína DEFICIENS/metabolismo , Flores/crecimiento & desarrollo , Flores/metabolismo , Expresión Génica , Regulación de la Expresión Génica de las Plantas/genética , Redes Reguladoras de Genes , Genotipo , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Modelos Biológicos , Monoterpenos/análisis , Monoterpenos/metabolismo , Mutación , Aceites Volátiles/análisis , Fenotipo , Hojas de la Planta/anatomía & histología , Hojas de la Planta/genética , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Interferencia de ARNRESUMEN
Several fleshy fruits are highly affected by cracking, a severe physiological disorder that compromises their quality and causes high economical losses to the producers. Cracking can occur due to physiological, genetic or environmental factors and may happen during fruit growth, development and ripening. Moreover, in fleshy fruits, exocarp plays an important role, acting as a mechanical protective barrier, defending against biotic or abiotic factors. Thus, when biochemical properties of the cuticle + epidermis + hypodermis are affected, cracks appear in the fruit skin. The identification of genes involved in development such as cell wall modifications, biosynthesis and transport of cuticular waxes, cuticular membrane deposition and associated transcription factors provides new insights to better understand how fruit cracking is affected by genetic factors. Amongst the major environmental stresses causing cracking are excessive water during fruit development, leading to imbalances in cations such as Ca. This review focus on expression of key genes in these pathways, in their influence in affected fruits and the potential for molecular breeding programs, aiming to develop cultivars more resistant to cracking under adverse environmental conditions.
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Ever since agriculture started, plants have been bred to obtain better yields, better fruits, or sustainable products under uncertain biotic and abiotic conditions. However, a new way to obtain products from plant cells emerged with the development of recombinant DNA technologies. This led to the possibility of producing exogenous molecules in plants. Furthermore, plant chemodiversity has been the main source of pharmacological molecules, opening a field of plant biotechnology directed to produce high quality plant metabolites. The need for different products by the pharma, cosmetics agriculture and food industry has pushed again to develop new procedures. These include cell production in bioreactors. While plant tissue and cell culture are an established technology, beginning over a hundred years ago, plant cell cultures have shown little impact in biotechnology projects, compared to bacterial, yeasts or animal cells. In this review we address the different types of bioreactors that are currently used for plant cell production and their usage for quality biomolecule production. We make an overview of Nicotiana tabacum, Nicotiana benthamiana, Oryza sativa, Daucus carota, Vitis vinifera and Physcomitrium patens as well-established models for plant cell culture, and some species used to obtain important metabolites, with an insight into the type of bioreactor and production protocols.
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Short term experiments have identified heat shock and cold response elements in many biological systems. However, the effect of long-term low or high temperatures is not well documented. To address this gap, we grew Antirrhinum majus plants from two-weeks old until maturity under control (normal) (22/16°C), cold (15/5°C), and hot (30/23°C) conditions for a period of two years. Flower size, petal anthocyanin content and pollen viability obtained higher values in cold conditions, decreasing in middle and high temperatures. Leaf chlorophyll content was higher in cold conditions and stable in control and hot temperatures, while pedicel length increased under hot conditions. The control conditions were optimal for scent emission and seed production. Scent complexity was low in cold temperatures. The transcriptomic analysis of mature flowers, followed by gene enrichment analysis and CNET plot visualization, showed two groups of genes. One group comprised genes controlling the affected traits, and a second group appeared as long-term adaptation to non-optimal temperatures. These included hypoxia, unsaturated fatty acid metabolism, ribosomal proteins, carboxylic acid, sugar and organic ion transport, or protein folding. We found a differential expression of floral organ identity functions, supporting the flower size data. Pollinator-related traits such as scent and color followed opposite trends, indicating an equilibrium for rendering the organs for pollination attractive under changing climate conditions. Prolonged heat or cold cause structural adaptations in protein synthesis and folding, membrane composition, and transport. Thus, adaptations to cope with non-optimal temperatures occur in basic cellular processes.
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The cactus Opuntia ficus-indica is a constitutive Crassulacean acid metabolism (CAM) species. Current knowledge of CAM metabolism suggests that the enzyme phosphoenolpyruvate carboxylase kinase (PPCK) is circadian regulated at the transcriptional level, whereas phosphoenolpyruvate carboxylase (PEPC), malate dehydrogenase (MDH), NADP-malic enzyme (NADP-ME), and pyruvate phosphate dikinase (PPDK) are posttranslationally controlled. As little transcriptomic data are available from obligate CAM plants, we created an expressed sequence tag database derived from different organs and developmental stages. Sequences were assembled, compared with sequences in the National Center for Biotechnology Information nonredundant database for identification of putative orthologs, and mapped using Kyoto Encyclopedia of Genes and Genomes Orthology and Gene Ontology. We identified genes involved in circadian regulation and CAM metabolism for transcriptomic analysis in plants grown in long days. We identified stable reference genes for quantitative polymerase chain reaction and found that OfiSAND, like its counterpart in Arabidopsis (Arabidopsis thaliana), and OfiTUB are generally appropriate standards for use in the quantification of gene expression in O. ficus-indica. Three kinds of expression profiles were found: transcripts of OfiPPCK oscillated with a 24-h periodicity; transcripts of the light-active OfiNADP-ME and OfiPPDK genes adapted to 12-h cycles, while transcript accumulation patterns of OfiPEPC and OfiMDH were arrhythmic. Expression of the circadian clock gene OfiTOC1, similar to Arabidopsis, oscillated with a 24-h periodicity, peaking at night. Expression of OfiCCA1 and OfiPRR9, unlike in Arabidopsis, adapted best to a 12-h rhythm, suggesting that circadian clock gene interactions differ from those of Arabidopsis. Our results indicate that the evolution of CAM metabolism could be the result of modified circadian regulation at both the transcriptional and posttranscriptional levels.
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Ácidos/metabolismo , Relojes Circadianos/genética , Ritmo Circadiano/genética , Regulación de la Expresión Génica de las Plantas , Opuntia/genética , Etiquetas de Secuencia Expresada , Regulación del Desarrollo de la Expresión Génica , Genes de Plantas/genética , Anotación de Secuencia Molecular , Opuntia/crecimiento & desarrollo , Filogenia , Estándares de Referencia , Reproducibilidad de los Resultados , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Homología de Secuencia de Ácido Nucleico , Factores de TiempoRESUMEN
Plant development is the result of an endogenous morphogenetic program that integrates environmental signals. The so-called circadian clock is a set of genes that integrates environmental inputs into an internal pacing system that gates growth and other outputs. Study of circadian growth responses requires high sampling rates to detect changes in growth and avoid aliasing. We have developed a flexible configurable growth chamber comprising a computer vision system that allows sampling rates ranging between one image per 30 s to hours/days. The vision system has a controlled illumination system, which allows the user to set up different configurations. The illumination system used emits a combination of wavelengths ensuring the optimal growth of species under analysis. In order to obtain high contrast of captured images, the capture system is composed of two CCD cameras, for day and night periods. Depending on the sample type, a flexible image processing software calculates different parameters based on geometric calculations. As a proof of concept we tested the system in three different plant tissues, growth of petunia- and snapdragon (Antirrhinum majus) flowers and of cladodes from the cactus Opuntia ficus-indica. We found that petunia flowers grow at a steady pace and display a strong growth increase in the early morning, whereas Opuntia cladode growth turned out not to follow a circadian growth pattern under the growth conditions imposed. Furthermore we were able to identify a decoupling of increase in area and length indicating that two independent growth processes are responsible for the final size and shape of the cladode.
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Inteligencia Artificial , Ritmo Circadiano , Diseño de Equipo , Desarrollo de la Planta , Fenómenos Fisiológicos de las Plantas , CalibraciónRESUMEN
BACKGROUND: The combination of computer vision devices such as multispectral cameras coupled with artificial intelligence has provided a major leap forward in image-based analysis of biological processes. Supervised artificial intelligence algorithms require large ground truth image datasets for model training, which allows to validate or refute research hypotheses and to carry out comparisons between models. However, public datasets of images are scarce and ground truth images are surprisingly few considering the numbers required for training algorithms. RESULTS: We created a dataset of 1,283 multidimensional arrays, using berries from five different grape varieties. Each array has 37 images of wavelengths between 488.38 and 952.76 nm obtained from single berries. Coupled to each multispectral image, we added a dataset with measurements including, weight, anthocyanin content, and Brix index for each independent grape. Thus, the images have paired measures, creating a ground truth dataset. We tested the dataset with 2 neural network algorithms: multilayer perceptron (MLP) and 3-dimensional convolutional neural network (3D-CNN). A perfect (100% accuracy) classification model was fit with either the MLP or 3D-CNN algorithms. CONCLUSIONS: This is the first public dataset of grape ground truth multispectral images. Associated with each multispectral image, there are measures of the weight, anthocyanins, and Brix index. The dataset should be useful to develop deep learning algorithms for classification, dimensionality reduction, regression, and prediction analysis.
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Antocianinas , Vitis , Inteligencia Artificial , Frutas , Procesamiento de Imagen Asistido por Computador , Aprendizaje AutomáticoRESUMEN
BACKGROUND: Relative calculation of differential gene expression in quantitative PCR reactions requires comparison between amplification experiments that include reference genes and genes under study. Ignoring the differences between their efficiencies may lead to miscalculation of gene expression even with the same starting amount of template. Although there are several tools performing PCR primer design, there is no tool available that predicts PCR efficiency for a given amplicon and primer pair. RESULTS: We have used a statistical approach based on 90 primer pair combinations amplifying templates from bacteria, yeast, plants and humans, ranging in size between 74 and 907 bp to identify the parameters that affect PCR efficiency. We developed a generalized additive model fitting the data and constructed an open source Web interface that allows the obtention of oligonucleotides optimized for PCR with predicted amplification efficiencies starting from a given sequence. CONCLUSIONS: pcrEfficiency provides an easy-to-use web interface allowing the prediction of PCR efficiencies prior to web lab experiments thus easing quantitative real-time PCR set-up. A web-based service as well the source code are provided freely at http://srvgen.upct.es/efficiency.html under the GPL v2 license.
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Reacción en Cadena de la Polimerasa/métodos , Bacterias/genética , Cartilla de ADN/genética , Humanos , Internet , Modelos Estadísticos , Plantas/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Programas InformáticosRESUMEN
Metabolomes comprise constitutive and non-constitutive metabolites produced due to physiological, genetic or environmental effects. However, finding constitutive metabolites and non-constitutive metabolites in large datasets is technically challenging. We developed gcProfileMakeR, an R package using standard Excel output files from an Agilent Chemstation GC-MS for automatic data analysis using CAS numbers. gcProfileMakeR has two filters for data preprocessing removing contaminants and low-quality peaks. The first function NormalizeWithinFiles, samples assigning retention times to CAS. The second function NormalizeBetweenFiles, reaches a consensus between files where compounds in close retention times are grouped together. The third function getGroups, establishes what is considered as Constitutive Profile, Non-constitutive by Frequency i.e., not present in all samples and Non-constitutive by Quality. Results can be plotted with the plotGroup function. We used it to analyse floral scent emissions in four snapdragon genotypes. These included a wild type, Deficiens nicotianoides and compacta affecting floral identity and RNAi:AmLHY targeting a circadian clock gene. We identified differences in scent constitutive and non-constitutive profiles as well as in timing of emission. gcProfileMakeR is a very useful tool to define constitutive and non-constitutive scent profiles. It also allows to analyse genotypes and circadian datasets to identify differing metabolites.
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Studies on the selection of floral traits usually consider pollinators and sometimes herbivores. However, humans also exert selection on floral traits of ornamental plants. We compared the preferences of bumblebees (Bombus terrestris), thrips (Frankliniella occidentalis), and humans for flowers of snapdragon. From a cross of two species, Antirrhinum majus and Antirrhinum linkianum, we selected four Recombinant Inbred Lines (RILs). We characterised scent emission from whole flowers and stamens, pollen content and viability, trichome density, floral shape, size and colour of floral parts. We tested the preferences of bumblebees, thrips, and humans for whole flowers, floral scent bouquets, stamen scent, and individual scent compounds. Humans and bumblebees showed preferences for parental species, whereas thrips preferred RILs. Colour and floral scent, in combination with other floral traits, seem relevant phenotypes for all organisms. Remarkably, visual traits override scent cues for bumblebees, although, scent is an important trait when bumblebees cannot see the flowers, and methyl benzoate was identified as a key attractant for them. The evolutionary trajectory of flowers is the result of multiple floral traits interacting with different organisms with different habits and modes of interaction.
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BACKGROUND: Identification of genes with invariant levels of gene expression is a prerequisite for validating transcriptomic changes accompanying development. Ideally expression of these genes should be independent of the morphogenetic process or environmental condition tested as well as the methods used for RNA purification and analysis. RESULTS: In an effort to identify endogenous genes meeting these criteria nine reference genes (RG) were tested in two Petunia lines (Mitchell and V30). Growth conditions differed in Mitchell and V30, and different methods were used for RNA isolation and analysis. Four different software tools were employed to analyze the data. We merged the four outputs by means of a non-weighted unsupervised rank aggregation method. The genes identified as optimal for transcriptomic analysis of Mitchell and V30 were EF1alpha in Mitchell and CYP in V30, whereas the least suitable gene was GAPDH in both lines. CONCLUSIONS: The least adequate gene turned out to be GAPDH indicating that it should be rejected as reference gene in Petunia. The absence of correspondence of the best-suited genes suggests that assessing reference gene stability is needed when performing normalization of data from transcriptomic analysis of flower and leaf development.
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Flores/crecimiento & desarrollo , Petunia/genética , Hojas de la Planta/crecimiento & desarrollo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/normas , Biología Computacional , Flores/genética , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Petunia/crecimiento & desarrollo , Hojas de la Planta/genética , ARN de Planta/genética , Estándares de Referencia , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Análisis de Secuencia de ADN , Programas InformáticosRESUMEN
BACKGROUND: Genetic recombination maps provide important frameworks for comparative genomics, identifying gene functions, assembling genome sequences and for breeding. The molecular recombination map currently available for the model eudicot Antirrhinum majus is the result of a cross with Antirrhinum molle, limiting its usefulness within A. majus. RESULTS: We created a molecular linkage map of A. majus based on segregation of markers in the F2 population of two inbred lab strains of A. majus. The resulting map consisted of over 300 markers in eight linkage groups, which could be aligned with a classical recombination map and the A. majus karyotype. The distribution of recombination frequencies and distorted transmission of parental alleles differed from those of a previous inter-species hybrid. The differences varied in magnitude and direction between chromosomes, suggesting that they had multiple causes. The map, which covered an estimated of 95% of the genome with an average interval of 2 cM, was used to analyze the distribution of a newly discovered family of MITE transposons and tested for its utility in positioning seven mutations that affect aspects of plant size. CONCLUSIONS: The current map has an estimated interval of 1.28 Mb between markers. It shows a lower level of transmission ratio distortion and a longer length than the previous inter-species map, making it potentially more useful. The molecular recombination map further indicates that the IDLE MITE transposons are distributed throughout the genome and are relatively stable. The map proved effective in mapping classical morphological mutations of A. majus.
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Antirrhinum/genética , Mapeo Cromosómico/métodos , Cromosomas de las Plantas/genética , Recombinación Genética , Cruzamientos Genéticos , Elementos Transponibles de ADN/genética , Etiquetas de Secuencia Expresada , Marcadores Genéticos/genética , Mutación , FenotipoRESUMEN
BACKGROUND: Human papillomavirus (HPV) genotyping is usually performed on cytological specimens with the aim of discerning between high- and low-risk genotypes. METHODS: Paraffin-embedded sections (n = 241) comprising 16 normal/benign (N/B) cervical sections, 72 low-grade squamous intraepithelial lesions (LSIL), 133 high-grade SIL (HSIL), 6 invasive carcinomas (cervical cancer), and 14 atypical immature metaplasias (AIMs) were DNA extracted and HPV genotyped. RESULTS: The most frequent HPV genotypes found were 16 and 58. HPV16 was detected in 0% N/B, 18.1% LSIL, 42.9% HSIL (p < 0.001), 50% carcinoma, and 35.7% AIM, whilst HPV58 was detected in 25.0, 20.8, 16.5, 0 and 35.7% of these lesions, respectively. DISCUSSION: The high prevalence of HPV58 and the low prevalence of HPV18 suggest the limited effectiveness of HPV vaccination in southeast Spain (prevention of 45.1% HSILs). The HPV genotype distribution profile in AIM suggests that these lesions are more similar to LSIL than HSIL pointing to a low risk of progression to cervical cancer. These results reinforce the necessity of assessing the specific genotype rather than distinguishing between high- or low-risk HPV. The use of histological section instead of cytological specimens for specific HPV genotyping would be very useful in order to ascertain the oncogenic potential of each of the genotypes found in a given area.
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Carcinoma de Células Escamosas/virología , Papillomavirus Humano 16/genética , Papillomavirus Humano 18/genética , Infecciones por Papillomavirus/virología , Neoplasias del Cuello Uterino/virología , Adulto , Anciano , Carcinoma de Células Escamosas/epidemiología , Carcinoma de Células Escamosas/patología , Femenino , Variación Genética , Genotipo , Papillomavirus Humano 16/aislamiento & purificación , Papillomavirus Humano 18/aislamiento & purificación , Humanos , Persona de Mediana Edad , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/patología , Vacunas contra Papillomavirus , Prevalencia , Factores de Riesgo , España/epidemiología , Neoplasias del Cuello Uterino/epidemiología , Neoplasias del Cuello Uterino/patología , Adulto JovenRESUMEN
The gene GIGANTEA (GI) appeared early in land plants. It is a single copy gene in most plants and is found in two to three copies in Solanaceae. We analyzed the silencing of one GI copy, Petunia hybrida GI1 (PhGI1), by hairpin RNAs in Petunia in order to gain knowledge about its range of functions. Decreased transcript levels of PhGI1 were accompanied also by a reduction of PhGI2. They were further associated with increased time period between two consecutive peaks for PhGI1 and CHANEL (PhCHL), the orthologue of the blue light receptor gene ZEITLUPE (ZTL), confirming its role in maintaining circadian rhythmicity. Silenced plants were bigger with modified internode length and increased leaf size while flowering time was not altered. We uncovered a new function for PhGI1 as silenced plants showed reduction of flower bud number and the appearance of two flower buds in the bifurcation point, were normally one flower bud and the inflorescence meristem separate. Furthermore, one of the flower buds consistently showed premature flower abortion. Flowers that developed fully were significantly smaller as a result of decreased cell size. Even so the circadian pattern of volatile emission was unchanged in the silenced lines, flowers emitted 20% less volatiles on fresh weight basis over 24 hours and showed changes in the scent profile. Our results indicate a novel role of PhGI1 in the development of reproductive organs in Petunia. PhGI1 therefore represses growth in vegetative plant parts, maintains the typical cymose inflorescence structure, and inhibits premature flower abortion.