166 research outputs found
Efectos del deshojado precoz sobre la composición aromática del vino Albariño en el valle del Salnés (D.O. Rías Baixas)
Este trabajo pretende estudiar los efectos del deshojado precoz sobre la
composición aromática del vino Albariño. Para ello se llevó a cabo el deshojado
en dos estados fenológicos de la planta, floración y cuajado y a dos
intensidades distintas, 4 y 8 hojas basales. Los resultados se compararon con
un control en el que no se realizó ningún deshojado. Los análisis químicos
clásicos no mostraron diferencias significativas para ningún parámetro
estudiado entre los vinos elaborados con los distintos tratamientos. La
identificación y cuantificación de los compuestos volátiles se realizó mediante
cromatografía de Gases (GC-FID). Los resultados obtenidos mostraron
diferencias significativas para 14 compuestos de los 36 analizados. Se podría
concluir, en este primer año de estudio, que el deshojado precoz es capaz de
aumentar la composición volátil del vino Albariño
Sintomatologia, etiología y algunos factores que inciden en la caída de plántulas de algodonero en Andalucía Occidental
Se describen los resultados de dos prospecciones sobre Caída de plántulas de algodonero
efectuadas en 1999 en 28 parcelas con historia de incidencia de la enfermedad
en Andalucía occidental. En la prospección temprana se recogieron 401 plantas de rodales
con problemas y se encontró una mayor incidencia de Rhizoctonia solani. En la tardía
se recogieron 976 plantas al azar y Thielaviopsis basteóla fue el que se encontró con
más frecuencia, notándose un incremento de la importancia de este hongo en los suelos
arcillosos al sur de Sevilla.
Se ha estudiado la sintomatologia presente y encontrado una asociación entre los
aislamientos de R. solani y la muerte de las plántulas y entre T. basicola y las necrosis
más oscuras y negras, comprobándose además que un elevado número de síndromes estuvieron
causados por agentes abióticos. Se presentan datos previos de las relaciones entre
la frecuencia de aislamientos de estos patógenos y algunas prácticas culturales como
fueron el quemado de los restos del cultivo anterior y las dosis del abonado de fondo. En
este trabajo se realizaron análisis de la germinación de la semilla sembrada por los agricultores
y se hacen consideraciones sobre el "vigor" de la semilla empleadaResults of two cotton surveys on cotton damping-off realized in west Andalucía
(Spain) are described. Twenty eight cotton fields known as disease prone were sampled.
At first survey 401 plants were collected from infected areas of the fields and
Rhizoctonia solani was the fungus most frequently recovered.
One month later, the same fields were randomly sampled and 976 plants were collected
founding a higher incidence of Thielaviopsis basicola, specially on clay soils
southern Seville.
Plants were classified by symptoms and related to isolated fungi. R. solani was associated
with seedling death and T. basicola with dark brown or black necrosis. A high
percentage of syndromes had an abiotic origin.
Preliminary conclusions on relationships between both fungi and fertilization management
and previous crops stubble are presented. Germination of seeds planted by
farmers was studied and some considerations about their vigor are made
Insights on fungal solid-state fermentation for waste valorization : conidia and chitinase production in different reactor configurations
Altres ajuts: Acord transformatiu CRUE-CSICAltres ajuts: Arnau Sala also thanks Universitat Aut'onoma de Barcelona for a predoctoral scholarship.Different reactor configurations are paired with a wide variety of agro-industrial wastes of different biodegradability to produce fungal conidia by solid-state fermentation. This work presents a preliminary comparative study between packed-bed and tray reactor configurations to produce Beauveria bassiana and Trichoderma harzianum conidia using two different substrates in terms of biodegradability: rice husk or beer draff complemented with wood chips. Conidia production, mean temperature and respiration indexes have been analysed in most of the presented reactor configurations. Both strains showed higher conidia production when using beer draff complemented with wood chips as substrate due to the use of a mixture as substrate. When working with beer draff, chitinase analyses obtained similar profiles in both strains but higher overall values using TH. Conidia and chitinase production maximums were not achieved at the same time, having 2-3 days of difference depending on the strain. No significant differences in mean temperature were shown between most of the performed fermentations. As a result of the present work, further scaling of both packed bed and tray configurations using beer draff and wood chips to produce BB or TH conidia would be advisable. More experiments should be performed to optimize both conidia and chitinase productions to enhance the quality of the final product
A second transmissible cancer in Tasmanian devils.
Clonally transmissible cancers are somatic cell lineages that are spread between individuals via the transfer of living cancer cells. There are only three known naturally occurring transmissible cancers, and these affect dogs, soft-shell clams, and Tasmanian devils, respectively. The Tasmanian devil transmissible facial cancer was first observed in 1996, and is threatening its host species with extinction. Until now, this disease has been consistently associated with a single aneuploid cancer cell lineage that we refer to as DFT1. Here we describe a second transmissible cancer, DFT2, in five devils located in southern Tasmania in 2014 and 2015. DFT2 causes facial tumors that are grossly indistinguishable but histologically distinct from those caused by DFT1. DFT2 bears no detectable cytogenetic similarity to DFT1 and carries a Y chromosome, which contrasts with the female origin of DFT1. DFT2 shows different alleles to both its hosts and DFT1 at microsatellite, structural variant, and major histocompatibility complex (MHC) loci, confirming that it is a second cancer that can be transmitted between devils as an allogeneic, MHC-discordant graft. These findings indicate that Tasmanian devils have spawned at least two distinct transmissible cancer lineages and suggest that transmissible cancers may arise more frequently in nature than previously considered. The discovery of DFT2 presents important challenges for the conservation of Tasmanian devils and raises the possibility that this species is particularly prone to the emergence of transmissible cancers. More generally, our findings highlight the potential for cancer cells to depart from their hosts and become dangerous transmissible pathogens.We thank Bill Brown, Phil Iles, Billie Lazenby, Jacinta Marr, Jane McGee, Sarah Peck, Holly Wiersma and Phil Wise for assistance with sample collection and curation. Adrian Baez-Ortega, Andrew Davis, Jo Hanuszewicz, Gina Kalodimos, Amanda Patchett, Narelle Phillips, Elizabeth Reid Swainscoat, Jim Richley, Rachel Stivicic and Jim Taylor assisted with surveying, laboratory analysis, data processing and display. We are grateful for support received from Mike Stratton, the Wellcome Trust Sanger Institute (WTSI) sequencing and informatics teams and the WTSI Cancer Genome Project. This work was supported by a Wellcome Trust Investigator Award (102942/Z/13/Z) and by grants from the Australian Research Council (ARC-DP130100715; ARC-LP130100218). Support was provided by Dr Eric Guiler Tasmanian Devil Research Grants and by the Save the Tasmanian Devil Program. JMCT was partly supported by a Marie Curie Fellowship (FP7-PEOPLE- 2012-IEF, 328364). Sequences associated with this paper have been deposited in Genbank with accession numbers KT188437 and KT188438
Evolutionary Dynamics of the Ty3/Gypsy LTR Retrotransposons in the Genome of Anopheles gambiae
Ty3/gypsy elements represent one of the most abundant and diverse LTR-retrotransposon (LTRr) groups in the Anopheles gambiae genome, but their evolutionary dynamics have not been explored in detail. Here, we conduct an in silico analysis of the distribution and abundance of the full complement of 1045 copies in the updated AgamP3 assembly. Chromosomal distribution of Ty3/gypsy elements is inversely related to arm length, with densities being greatest on the X, and greater on the short versus long arms of both autosomes. Taking into account the different heterochromatic and euchromatic compartments of the genome, our data suggest that the relative abundance of Ty3/gypsy LTRrs along each chromosome arm is determined mainly by the different proportions of heterochromatin, particularly pericentric heterochromatin, relative to total arm length. Additionally, the breakpoint regions of chromosomal inversion 2La appears to be a haven for LTRrs. These elements are underrepresented more than 7-fold in euchromatin, where 33% of the Ty3/gypsy copies are associated with genes. The euchromatin on chromosome 3R shows a faster turnover rate of Ty3/gypsy elements, characterized by a deficit of proviral sequences and the lowest average sequence divergence of any autosomal region analyzed in this study. This probably reflects a principal role of purifying selection against insertion for the preservation of longer conserved syntenyc blocks with adaptive importance located in 3R. Although some Ty3/gypsy LTRrs show evidence of recent activity, an important fraction are inactive remnants of relatively ancient insertions apparently subject to genetic drift. Consistent with these computational predictions, an analysis of the occupancy rate of putatively older insertions in natural populations suggested that the degenerate copies have been fixed across the species range in this mosquito, and also are shared with the sibling species Anopheles arabiensis
Subclone eradication analysis identifies targets for enhanced cancer therapy and reveals L1 retrotransposition as a dynamic source of cancer heterogeneity
Treatment-eradicated cancer subclones have been reported in leukemia and have recently been detected in solid tumors. Here we introduce Differential Subclone Eradication and Resistance Analysis (DSER), a method developed to identify molecular targets for improved therapy by direct comparison of genomic features of eradicated and resistant subclones in pre- and post-treatment samples from a patient with BRCA2-deficient metastatic prostate cancer. FANCI and EYA4 were identified as candidate DNA repair-related targets for converting subclones from resistant to eradicable, and RNAi-mediated depletion of FANCI confirmed it as a potential target. The EYA4 alteration was associated with adjacent L1 transposon insertion during cancer evolution upon treatment, raising questions surrounding the role of therapy in L1 activation. Both carboplatin and enzalutamide turned on L1 transposon machinery in LNCaP and VCaP but not in PC-3 and 22Rv1 prostate cancer cell lines. L1 activation in LNCaP and VCaP was inhibited by the antiretroviral drug azidothymidine. L1 activation was also detected post-castration in LuCaP 77 and LuCaP 105 xenograft models and post-chemotherapy in previously published time-series transcriptomic data from SCC25 head and neck cancer cells. In conclusion DSER provides an informative intermediate step toward effective precision cancer medicine and should be tested in future studies, especially those including dramatic but temporary metastatic tumor regression. L1 transposon activation may be a modifiable source of cancer genomic heterogeneity, suggesting the potential of leveraging newly discovered triggers and blockers of L1 activity to overcome therapy resistance
Novel transposable elements from Anopheles gambiae
<p>Abstract</p> <p>Background</p> <p>Transposable elements (TEs) are DNA sequences, present in the genome of most eukaryotic organisms that hold the key characteristic of being able to mobilize and increase their copy number within chromosomes. These elements are important for eukaryotic genome structure and evolution and lately have been considered as potential drivers for introducing transgenes into pathogen-transmitting insects as a means to control vector-borne diseases. The aim of this work was to catalog the diversity and abundance of TEs within the <it>Anopheles gambiae </it>genome using the PILER tool and to consolidate a database in the form of a hyperlinked spreadsheet containing detailed and readily available information about the TEs present in the genome of <it>An. gambiae</it>.</p> <p>Results</p> <p>Here we present the spreadsheet named AnoTExcel that constitutes a database with detailed information on most of the repetitive elements present in the genome of the mosquito. Despite previous work on this topic, our approach permitted the identification and characterization both of previously described and novel TEs that are further described in detailed.</p> <p>Conclusions</p> <p>Identification and characterization of TEs in a given genome is important as a way to understand the diversity and evolution of the whole set of TEs present in a given species. This work contributes to a better understanding of the landscape of TEs present in the mosquito genome. It also presents a novel platform for the identification, analysis, and characterization of TEs on sequenced genomes.</p
Genetic Diversity in Wheat: Analysis using Diversity Arrays Technology (DArT) in bread and durum wheats
With increasing demands on the quality and quantity of food required now and in the future, improvements to current agriculture practices are required. Increased food production requires utilisation of more agricultural land, pushing crops into non- traditional areas. The need for advances in agricultural technologies are not only required for current crop varieties, but for new varieties with increased tolerance to environmental stresses. Technological improvement means better crop yields and reduced land, water, fertilizer and pesticide use. Diversity Arrays Technology (DArT) was used to study wheat diversity, specifically to identify polymorphic markers between various wheat cultivars for use in marker- assisted breeding programs. The hybridisation based technology was used to analyse various bread and durum wheat cultivars for increased understanding of genomic diversity. Analysis shows that DArT is able to discriminate between tissue samples from wheat cultivars grown under various environmental stresses with polymorphic markers identified between samples treated with differing salt, light and temperature conditions. Epigenetic diversity was analysed through methylation detection using DArT to identify a list of candidate polymorphic markers. Markers were identified using the methylation sensitive restriction enzyme McrBC to generate control and treated targets. Diversity through cultivar exploration, looking at breeding experiments between cultivars with phenotypic extremes to examine salt tolerance versus in-tolerance using DArT produced a recombinant inbred line genetic linkage map. Bulk segregant analysis was also used to group phenotypic samples. Candidate markers were identified between cultivars that can be used to genotyping tetraploid and hexaploid wheat cultivars for germplasm identification. In addition, the identification of trait-linked molecular markers, such as salt resistance, plant breeders can genotype individual plants and populations of cultivars to determine the most suitable cultivar to plant that best complements to its local environment. This eliminates the need for multiple planting cycles to optimize crop selections, and gives the plant breeder the highest possible chance for crop success (yield, quality, performance and cost)
Genome of Rhodnius prolixus, an insect vector of Chagas disease, reveals unique adaptations to hematophagy and parasite infection
Rhodnius prolixus not only has served as a model organism for the study of insect physiology, but also is a major vector of Chagas disease, an illness that affects approximately seven million people worldwide. We sequenced the genome of R. prolixus, generated assembled sequences covering 95% of the genome ( approximately 702 Mb), including 15,456 putative protein-coding genes, and completed comprehensive genomic analyses of this obligate blood-feeding insect. Although immune-deficiency (IMD)-mediated immune responses were observed, R. prolixus putatively lacks key components of the IMD pathway, suggesting a reorganization of the canonical immune signaling network. Although both Toll and IMD effectors controlled intestinal microbiota, neither affected Trypanosoma cruzi, the causal agent of Chagas disease, implying the existence of evasion or tolerance mechanisms. R. prolixus has experienced an extensive loss of selenoprotein genes, with its repertoire reduced to only two proteins, one of which is a selenocysteine-based glutathione peroxidase, the first found in insects. The genome contained actively transcribed, horizontally transferred genes from Wolbachia sp., which showed evidence of codon use evolution toward the insect use pattern. Comparative protein analyses revealed many lineage-specific expansions and putative gene absences in R. prolixus, including tandem expansions of genes related to chemoreception, feeding, and digestion that possibly contributed to the evolution of a blood-feeding lifestyle. The genome assembly and these associated analyses provide critical information on the physiology and evolution of this important vector species and should be instrumental for the development of innovative disease control methods
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