229 research outputs found
Adaptive genomic structural variation in the grape powdery mildew pathogen, Erysiphe necator.
BackgroundPowdery mildew, caused by the obligate biotrophic fungus Erysiphe necator, is an economically important disease of grapevines worldwide. Large quantities of fungicides are used for its control, accelerating the incidence of fungicide-resistance. Copy number variations (CNVs) are unbalanced changes in the structure of the genome that have been associated with complex traits. In addition to providing the first description of the large and highly repetitive genome of E. necator, this study describes the impact of genomic structural variation on fungicide resistance in Erysiphe necator.ResultsA shotgun approach was applied to sequence and assemble the genome of five E. necator isolates, and RNA-seq and comparative genomics were used to predict and annotate protein-coding genes. Our results show that the E. necator genome is exceptionally large and repetitive and suggest that transposable elements are responsible for genome expansion. Frequent structural variations were found between isolates and included copy number variation in EnCYP51, the target of the commonly used sterol demethylase inhibitor (DMI) fungicides. A panel of 89 additional E. necator isolates collected from diverse vineyard sites was screened for copy number variation in the EnCYP51 gene and for presence/absence of a point mutation (Y136F) known to result in higher fungicide tolerance. We show that an increase in EnCYP51 copy number is significantly more likely to be detected in isolates collected from fungicide-treated vineyards. Increased EnCYP51 copy numbers were detected with the Y136F allele, suggesting that an increase in copy number becomes advantageous only after the fungicide-tolerant allele is acquired. We also show that EnCYP51 copy number influences expression in a gene-dose dependent manner and correlates with fungal growth in the presence of a DMI fungicide.ConclusionsTaken together our results show that CNV can be adaptive in the development of resistance to fungicides by providing increasing quantitative protection in a gene-dosage dependent manner. The results of this work not only demonstrate the effectiveness of using genomics to dissect complex traits in organisms with very limited molecular information, but also may have broader implications for understanding genomic dynamics in response to strong selective pressure in other pathogens with similar genome architectures
Comparative genomics of the Liberibacter genus reveals widespread diversity in genomic content and positive selection history
‘Candidatus Liberibacter’ is a group of bacterial species that are obligate intracellular plant pathogens and cause Huanglongbing disease of citrus trees and Zebra Chip in potatoes. Here, we examined the extent of intra- and interspecific genetic diversity across the genus using comparative genomics. Our approach examined a wide set of Liberibacter genome sequences including five pathogenic species and one species not known to cause disease. By performing comparative genomics analyses, we sought to understand the evolutionary history of this genus and to identify genes or genome regions that may affect pathogenicity. With a set of 52 genomes, we performed comparative genomics, measured genome rearrangement, and completed statistical tests of positive selection. We explored markers of genetic diversity across the genus, such as average nucleotide identity across the whole genome. These analyses revealed the highest intraspecific diversity amongst the ‘Ca. Liberibacter solanacearum’ species, which also has the largest plant host range. We identified sets of core and accessory genes across the genus and within each species and measured the ratio of nonsynonymous to synonymous mutations (dN/dS) across genes. We identified ten genes with evidence of a history of positive selection in the Liberibacter genus, including genes in the Tad complex, which have been previously implicated as being highly divergent in the ‘Ca. L. capsica’ species based on high values of dN
Determinación de la prevalencia de ectoparásitos y helmintos gastrointestinales en aves de granjas en los departamentos de San Marcos, Retalhuleu, Suchitepéquez, Escuintla, Santa Rosa y Jutiapa
La prevalencia de Ectoparásitos identificados en los departamentos de la costa sur fueron: Piojos; Menopon gallinae 11.49%, Menacanthus stramineus 1.23%, Lipeurus caponi 0.26%s, Goniodes giga 3.16%s, goniocotes gallinae 3.38%, Pulgas; Echidnophaga gallinácea 0.22%, Ácaros, Dermanyssus gallinae 16.53%, Cnemidocoptes mutans 0.04%. La prevalencia de Los helmintos gastrointestinales encontrados en los departamentos de la costa sur fueron: Nematodos; Ascaridia galli 32.28%, Heterakis gallinarum 4.21%, Strongyloides avium 0.17%, Capillaria sp 1.49%, Cestodos; Raillietina sp 12%. Los principales factores identificados y relacionados con la presencia de las parasitosis fueron: El uso de antiparasitarios, la limpieza y desinfección, la presencia de vectores y hospederos intermediario
Developmental and metabolic plasticity of white-skinned grape berries in response to <i>Botrytis cinerea</i> during noble rot
Noble rot results from exceptional infections of ripe grape (Vitis vinifera) berries by Botrytis cinerea. Unlike bunch rot, noble rot promotes favorable changes in grape berries and the accumulation of secondary metabolites that enhance wine grape composition. Noble rot-infected berries of cv Sémillon, a white-skinned variety, were collected over 3 years from a commercial vineyard at the same time that fruit were harvested for botrytized wine production. Using an integrated transcriptomics and metabolomics approach, we demonstrate that noble rot alters the metabolism of cv Sémillon berries by inducing biotic and abiotic stress responses as well as ripening processes. During noble rot, B. cinerea induced the expression of key regulators of ripening-associated pathways, some of which are distinctive to the normal ripening of red-skinned cultivars. Enhancement of phenylpropanoid metabolism, characterized by a restricted flux in white-skinned berries, was a common outcome of noble rot and red-skinned berry ripening. Transcript and metabolite analyses together with enzymatic assays determined that the biosynthesis of anthocyanins is a consistent hallmark of noble rot in cv Sémillon berries. The biosynthesis of terpenes and fatty acid aroma precursors also increased during noble rot. We finally characterized the impact of noble rot in botrytized wines. Altogether, the results of this work demonstrated that noble rot causes a major reprogramming of berry development and metabolism. This desirable interaction between a fruit and a fungus stimulates pathways otherwise inactive in white-skinned berries, leading to a greater accumulation of compounds involved in the unique flavor and aroma of botrytized wines.Facultad de Ciencias Agrarias y Forestale
Synthesis and in vitro evaluation of an antiangiogenic cancerspecific dual-targeting 177Lu-Au-nanoradiopharmaceutical
The aim of this research was to synthesize and chemically characterize a cancer-specific 177Lu-Aunanoradiopharmaceutical based on gold nanoparticles (NPs), the nuclear localization sequence (NLS)-Arg-Gly- Asp peptide and an aptamer (HS-pentyl-pegaptanib) to target both the a(v)b(3) integrin and the vascular endothelial growth factor (VEGF) overexpressed in the tumor neovasculature, as well as to evaluate by the tube formation assay, the nanosystem capability to inhibit angiogenesis. 177Lu-NP-RGD-NLS-Aptamer was obtained with a radiochemical purity of 99 ± 1%. Complete inhibition of tube formation (angiogenesis) was demonstrated when endothelial cells (EA.hy926), cultured in a 3D-extracellular matrix support, were treated with the developed nanosystem.Mexican National Council of Science and Technology (CONACYT-SEP-CB-2014-01-242443)
Developmental and metabolic plasticity of white-skinned grape berries in response to <i>Botrytis cinerea</i> during noble rot
Noble rot results from exceptional infections of ripe grape (Vitis vinifera) berries by Botrytis cinerea. Unlike bunch rot, noble rot promotes favorable changes in grape berries and the accumulation of secondary metabolites that enhance wine grape composition. Noble rot-infected berries of cv Sémillon, a white-skinned variety, were collected over 3 years from a commercial vineyard at the same time that fruit were harvested for botrytized wine production. Using an integrated transcriptomics and metabolomics approach, we demonstrate that noble rot alters the metabolism of cv Sémillon berries by inducing biotic and abiotic stress responses as well as ripening processes. During noble rot, B. cinerea induced the expression of key regulators of ripening-associated pathways, some of which are distinctive to the normal ripening of red-skinned cultivars. Enhancement of phenylpropanoid metabolism, characterized by a restricted flux in white-skinned berries, was a common outcome of noble rot and red-skinned berry ripening. Transcript and metabolite analyses together with enzymatic assays determined that the biosynthesis of anthocyanins is a consistent hallmark of noble rot in cv Sémillon berries. The biosynthesis of terpenes and fatty acid aroma precursors also increased during noble rot. We finally characterized the impact of noble rot in botrytized wines. Altogether, the results of this work demonstrated that noble rot causes a major reprogramming of berry development and metabolism. This desirable interaction between a fruit and a fungus stimulates pathways otherwise inactive in white-skinned berries, leading to a greater accumulation of compounds involved in the unique flavor and aroma of botrytized wines.Facultad de Ciencias Agrarias y Forestale
Developmental and metabolic plasticity of white-skinned grape berries in response to Botrytis cinerea during noble rot
Lead, Cadmium and Cobalt (Pb, Cd, and Co) Leaching of Glass-Clay Containers by pH Effect of Food
Recent studies have shown that handcrafted glass-clay containers are a health risk because they can be contaminated by heavy metals, which can be transferred to food, thus reaching the human body to potentially cause illness. Therefore, in the present work, we evaluate the leaching of lead, cadmium, and cobalt from glass-clay containers into two types of food: tomato sauce (salsa), and chickpea puree. The containers were obtained from four regions in the Mexican state of Hidalgo. Repetitive extractions from the containers were carried out to quantify the leaching of the heavy metals into the salsa, the chickpea puree, and acetic acid using the technique proposed by the USFDA. The results show that greater use of the containers leads to more leaching of heavy metals into both types of food and into the acetic acid, with the greatest metal extraction recorded for the Ixmiquilpan vessels. These results indicate that the metals present in the glass-clay containers leach into the food and that increased reuse increases the risk to the people who use them in food preparation
Investigaciones sobre paz, conflictos y violencia en México
En cumplimiento a la normatividad sobre el acceso abierto de la investigación científica, esta obra se pone a disposición del público en su versión electrónica en el repositorio de la uaemex (http:// ri.uaemex.mx) para su uso en línea con fines académicos y no de lucro, por lo que se prohíbe la reproducción parcial o total, directa o indirecta del contenido de esta presentación impresa sin contar previamente con la autorización expresa y por escrito de GEMAporrúa, en términos de lo así previsto por la Ley Federal del Derecho de Autor y, en su caso, por los tratados internacionales aplicables.Bajo la idea de que "merecemos un mundo distinto al que tenemos", este libro ofrece una serie de reflexiones y análisis sobre la paz, algunos conflictos y ciertas formas de violencia desde el "campo" interdisciplinario denominado Estudios para la Paz y el Desarrollo, que se alienta en la Universidad Autónoma del Estado de México, dentro del programa de Maestría del mismo nombre. Quienes escriben en el texto se ubican: o en el ángulo de la investigación para la paz en estricto sentido, o en el ángulo de la investigación para la paz en sentido amplio, que se estimulan y difunden en dicho programa, y que, desde diferentes posturas, alientan escenarios o acciones encaminadas hacia la paz. El libro está dividido en tres secciones, mismas que corresponden a los temas de paz, conflictos y violencia, donde aparecen reflexiones teóricas o empíricas de autores formados o relacionados en el campo
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