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1.
BMC Genomics ; 23(1): 735, 2022 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-36316643

RESUMEN

BACKGROUND: Soil salinity is a problem in more than 100 countries across all continents. It is one of the abiotic stress that threatens agriculture the most, negatively affecting crops and reducing productivity. Transcriptomics is a technology applied to characterize the transcriptome in a cell, tissue, or organism at a given time via RNA-Seq, also known as full-transcriptome shotgun sequencing. This technology allows the identification of most genes expressed at a particular stage, and different isoforms are separated and transcript expression levels measured. Once determined by this technology, the expression profile of a gene must undergo validation by another, such as quantitative real-time PCR (qRT-PCR). This study aimed to select, annotate, and validate stress-inducible genes-and their promoters-differentially expressed in the leaves of oil palm (Elaeis guineensis) plants under saline stress. RESULTS: The transcriptome analysis led to the selection of 14 genes that underwent structural and functional annotation, besides having their expression validated using the qRT-PCR technique. When compared, the RNA-Seq and qRT-PCR profiles of those genes resulted in some inconsistencies. The structural and functional annotation analysis of proteins coded by the selected genes showed that some of them are orthologs of genes reported as conferring resistance to salinity in other species. There were those coding for proteins related to the transport of salt into and out of cells, transcriptional regulatory activity, and opening and closing of stomata. The annotation analysis performed on the promoter sequence revealed 22 distinct types of cis-acting elements, and 14 of them are known to be involved in abiotic stress. CONCLUSION: This study has helped validate the process of an accurate selection of genes responsive to salt stress with a specific and predefined expression profile and their promoter sequence. Its results also can be used in molecular-genetics-assisted breeding programs. In addition, using the identified genes is a window of opportunity for strategies trying to relieve the damages arising from the salt stress in many glycophyte crops with economic importance.


Asunto(s)
Arecaceae , Regulación de la Expresión Génica de las Plantas , Fitomejoramiento , Estrés Salino/genética , Perfilación de la Expresión Génica , Arecaceae/genética , Transcriptoma
2.
PLoS Genet ; 12(8): e1005876, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27512984

RESUMEN

Black Sigatoka or black leaf streak disease, caused by the Dothideomycete fungus Pseudocercospora fijiensis (previously: Mycosphaerella fijiensis), is the most significant foliar disease of banana worldwide. Due to the lack of effective host resistance, management of this disease requires frequent fungicide applications, which greatly increase the economic and environmental costs to produce banana. Weekly applications in most banana plantations lead to rapid evolution of fungicide-resistant strains within populations causing disease-control failures throughout the world. Given its extremely high economic importance, two strains of P. fijiensis were sequenced and assembled with the aid of a new genetic linkage map. The 74-Mb genome of P. fijiensis is massively expanded by LTR retrotransposons, making it the largest genome within the Dothideomycetes. Melting-curve assays suggest that the genomes of two closely related members of the Sigatoka disease complex, P. eumusae and P. musae, also are expanded. Electrophoretic karyotyping and analyses of molecular markers in P. fijiensis field populations showed chromosome-length polymorphisms and high genetic diversity. Genetic differentiation was also detected using neutral markers, suggesting strong selection with limited gene flow at the studied geographic scale. Frequencies of fungicide resistance in fungicide-treated plantations were much higher than those in untreated wild-type P. fijiensis populations. A homologue of the Cladosporium fulvum Avr4 effector, PfAvr4, was identified in the P. fijiensis genome. Infiltration of the purified PfAVR4 protein into leaves of the resistant banana variety Calcutta 4 resulted in a hypersensitive-like response. This result suggests that Calcutta 4 could carry an unknown resistance gene recognizing PfAVR4. Besides adding to our understanding of the overall Dothideomycete genome structures, the P. fijiensis genome will aid in developing fungicide treatment schedules to combat this pathogen and in improving the efficiency of banana breeding programs.


Asunto(s)
Ascomicetos/genética , Resistencia a la Enfermedad/genética , Musa/genética , Enfermedades de las Plantas/genética , Hojas de la Planta/genética , Ascomicetos/patogenicidad , Cruzamiento , Cromosomas Fúngicos/genética , Variación Genética , Genoma Fúngico , Genotipo , Musa/crecimiento & desarrollo , Musa/microbiología , Enfermedades de las Plantas/microbiología , Hojas de la Planta/microbiología , Retroelementos/genética
3.
Metabolomics ; 14(10): 142, 2018 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-30830392

RESUMEN

INTRODUCTION: Oil palm (E. guineensis), the most consumed vegetable oil in the world, is affected by fatal yellowing (FY), a condition that can lead to the plant's death. Although studies have been performed since the 1980s, including investigations of biotic and abiotic factors, FY's cause remains unknown and efforts in researches are still necessary. OBJECTIVES: This work aims to investigate the metabolic expression in plants affected by FY using an untargeted metabolomics approach. METHOD: Metabolic fingerprinting analysis of oil palm leaves was performed using ultra high liquid chromatography-electrospray ionization-mass spectrometry (UHPLC-ESI-MS). Chemometric analysis, using principal component analysis (PCA) and partial least square discriminant analysis (PLS-DA), was applied to data analysis. Metabolites identification was performed by high resolution mass spectrometry (HRMS), MS/MS experiments and comparison with databases and literature. RESULTS: Metabolomics analysis based on MS detected more than 50 metabolites in oil palm leaf samples. PCA and PLS-DS analysis provided group segregation and classification of symptomatic and non-symptomatic FY samples, with a great external validation of the results. Nine differentially expressed metabolites were identified as glycerophosphorylcholine, arginine, asparagine, apigenin 6,8-di-C-hexose, tyramine, chlorophyllide, 1,2-dihexanoyl-sn-glycero-3-phosphoethanolamine, proline and malvidin 3-glucoside-5-(6″-malonylglucoside). Metabolic pathways and biological importance of those metabolites were assigned. CONCLUSION: Nine metabolites were detected in a higher concentration in non-symptomatic FY plants. Seven are related to stress factors i.e. plant defense and nutrient absorption, which can be affected by the metabolic depression of these compounds. Two of those metabolites (glycerophosphorylcholine and 1,2-dihexanoyl-sn-glycero-3-phosphoethanolamine) are presented as potential biomarkers, since they have no known direct relation to plant stress.


Asunto(s)
Arecaceae/metabolismo , Metabolómica , Aceite de Palma/metabolismo , Enfermedades de las Plantas , Arecaceae/química , Cromatografía Líquida de Alta Presión , Análisis de los Mínimos Cuadrados , Aceite de Palma/análisis , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Análisis de Componente Principal , Espectrometría de Masa por Ionización de Electrospray
4.
Diabetes Metab Res Rev ; 33(3)2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27507764

RESUMEN

CONTEXT: Metabolic syndrome (MetS) shares several similarities with hypercortisolism. OBJECTIVES: To evaluate hypothalamic-pituitary-adrenal (HPA) axis sensitivity to dexamethasone (DEX), NR3C1 single nucleotide polymorphisms (SNPs), and expression of glucocorticoid receptor (GR) isoforms and cytokines in peripheral immune cells of MetS patients and controls. DESIGN: Prospective study with 40 MetS patients and 40 controls was conducted at the Ribeirão Preto Medical School University Hospital. METHODS: Plasma and salivary cortisol were measured in basal conditions and after 0.25, 0.5, and 1 mg of DEX given at 2300 h. In addition, p.N363S (rs6195), p.ER22/23EK (rs6189-6190), and BclI (rs41423247) SNPs were evaluated by quantitative polymerase chain reaction allelic discrimination. Exons 3 to 9 and exon/intron boundaries of NR3C1 were sequenced. GR isoforms and cytokines (IL1B, IL2, IL4, IL6, IL8, IL10, IFNγ, TNFα) expression were assessed by quantitative polymerase chain reaction. RESULTS: Plasma and salivary cortisol (nmol/L) after 1-mg DEX were higher in MetS patients compared with controls (PF: 70.2 ± 17.3 vs 37.9 ± 2.6, P = .02, and SF: 4.9 ± 1.7 vs 2.2 ± 0.3, P < .0001). After all DEX doses, a lower number of MetS patients suppressed plasma and salivary cortisol compared with controls. The BclI genotypic frequencies (%) differed between patients (CC:56/CG:44) and controls (CC:50/CG:32.5/GG:17.5) (P = .03). The GRß was overexpressed (fold = 100.0; P = .002) and IL4 (fold = -265.0; P < .0001) was underexpressed in MetS. CONCLUSION: MetS patients exhibited decreased HPA sensitivity to glucocorticoid feedback. Moreover, the BclI polymorphism lower frequency, GRß overexpression, and IL4 underexpression might underlie the molecular mechanism of glucocorticoid resistance in MetS. Thus, HPA axis dysregulation might contribute to MetS pathogenesis.


Asunto(s)
Sistema Hipotálamo-Hipofisario/patología , Síndrome Metabólico/fisiopatología , Sistema Hipófiso-Suprarrenal/patología , Polimorfismo de Nucleótido Simple/genética , Receptores de Glucocorticoides/metabolismo , Adulto , Anciano , Antiinflamatorios/uso terapéutico , Biomarcadores/análisis , Estudios de Casos y Controles , Citocinas/metabolismo , Dexametasona/uso terapéutico , Femenino , Estudios de Seguimiento , Humanos , Hidrocortisona/sangre , Sistema Hipotálamo-Hipofisario/efectos de los fármacos , Sistema Hipotálamo-Hipofisario/metabolismo , Masculino , Síndrome Metabólico/tratamiento farmacológico , Síndrome Metabólico/metabolismo , Persona de Mediana Edad , Sistema Hipófiso-Suprarrenal/efectos de los fármacos , Sistema Hipófiso-Suprarrenal/metabolismo , Pronóstico , Estudios Prospectivos , Isoformas de Proteínas , Receptores de Glucocorticoides/genética
5.
Plants (Basel) ; 11(13)2022 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-35807707

RESUMEN

Oil palm (Elaeis guineensis Jacq.) is the number one source of consumed vegetable oil nowadays. It is cultivated in areas of tropical rainforest, where it meets its natural condition of high rainfall throughout the year. The palm oil industry faces criticism due to a series of practices that was considered not environmentally sustainable, and it finds itself under pressure to adopt new and innovative procedures to reverse this negative public perception. Cultivating this oilseed crop outside the rainforest zone is only possible using artificial irrigation. Close to 30% of the world's irrigated agricultural lands also face problems due to salinity stress. Consequently, the research community must consider drought and salinity together when studying to empower breeding programs in order to develop superior genotypes adapted to those potential new areas for oil palm cultivation. Multi-Omics Integration (MOI) offers a new window of opportunity for the non-trivial challenge of unraveling the mechanisms behind multigenic traits, such as drought and salinity tolerance. The current study carried out a comprehensive, large-scale, single-omics analysis (SOA), and MOI study on the leaves of young oil palm plants submitted to very high salinity stress. Taken together, a total of 1239 proteins were positively regulated, and 1660 were negatively regulated in transcriptomics and proteomics analyses. Meanwhile, the metabolomics analysis revealed 37 metabolites that were upregulated and 92 that were downregulated. After performing SOA, 436 differentially expressed (DE) full-length transcripts, 74 DE proteins, and 19 DE metabolites underwent MOI analysis, revealing several pathways affected by this stress, with at least one DE molecule in all three omics platforms used. The Cysteine and methionine metabolism (map00270) and Glycolysis/Gluconeogenesis (map00010) pathways were the most affected ones, each one with 20 DE molecules.

6.
Front Plant Sci ; 13: 869105, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35665181

RESUMEN

The multipurpose tree Gliricidia sepium (Jacq.) Walp. adapts to a very high level of salt stress (≥20 dS m-1) and resumes the production of new leaves around 2 weeks after losing all leaves due to abrupt salinity stress. The integration of metabolome and transcriptome profiles from gliricidia leaves points to a central role of the phenylpropanoid biosynthesis pathway in the short-term response to salinity stress. In this study, a deeper untargeted metabolomics analysis of the leaves and roots of young gliricidia plants was conducted to characterize the mechanism(s) behind this adaptation response. The polar and lipidic fractions from leaf and root samples were extracted and analyzed on a UHPLC.ESI.Q-TOF.HRMS system. Acquired data were analyzed using the XCMS Online, and MetaboAnalyst platforms, via three distinct and complementary strategies. Together, the results obtained first led us to postulate that these plants are salt-excluding plants, which adapted to high salinity stress via two salt-excluding mechanisms, starting in the canopy-severe defoliation-and concluding in the roots-limited entry of Na. Besides that, it was possible to show that the phenylpropanoid biosynthesis pathway plays a role throughout the entire adaptation response, starting in the short term and continuing in the long one. The roots metabolome analysis revealed 11 distinct metabolic pathways affected by salt stress, and the initial analysis of the two most affected ones-steroid biosynthesis and lysine biosynthesis-led us also to postulate that the accumulation of lignin and some phytosterols, as well as lysine biosynthesis-but not degradation, play a role in promoting the adaptation response. However, additional studies are necessary to investigate these hypotheses.

7.
Front Plant Sci ; 13: 970113, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36212369

RESUMEN

Oil palm (Elaeis guineensis Jacq.) is a oilseed crop of great economic importance drastically affected by abiotic stresses. MicroRNAs (miRNAs) play crucial roles in transcription and post-transcription regulation of gene expression, being essential molecules in the response of plants to abiotic stress. To better understand the molecular mechanisms behind the response of young oil palm plants to drought stress, this study reports on the prediction and characterization of miRNAs and their putative target genes in the apical leaf of plants subjected to 14 days of water deprivation. Then, the data from this study were compared to the data from a similar study that focused on salinity stress. Both, the drought-and salt-responsive miRNAs and their putative target genes underwent correlation analysis to identify similarities and dissimilarities among them. Among the 81 identified miRNAs, 29 are specific for oil palm, including two (egu-miR28ds and egu-miR29ds) new ones - described for the first time. As for the expression profile, 62 miRNAs were significantly differentially expressed under drought stress, being five up-regulated (miR396e, miR159b, miR529b, egu-miR19sds, and egu-miR29ds) and 57 down-regulated. Transcription factors, such as MYBs, HOXs, and NF-Ys, were predicted as putative miRNA-target genes in oil palm under water deprivation; making them the most predominant group of such genes. Finally, the correlation analysis study revealed a group of putative target genes with similar behavior under salt and drought stresses. Those genes that are upregulated by these two abiotic stresses encode lncRNAs and proteins linked to stress tolerance, stress memory, modulation of ROS signaling, and defense response regulation to abiotic and biotic stresses. In summary, this study provides molecular evidence for the possible involvement of miRNAs in the drought stress response in oil palm. Besides, it shows that, at the molecular level, there are many similarities in the response of young oil palm plants to these two abiotic stresses.

8.
Plant Genome ; 15(1): e20182, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34964552

RESUMEN

Soil salinity is one abiotic stress that threatens agriculture in more than 100 countries. Gliricidia [Gliricidia sepium (Jacq.) Kunth] is a multipurpose tree known for its ability to adapt to a wide range of soils; however, its tolerance limits and responses to salt stress are not yet well understood. In this study, after characterizing the morphophysiological responses of young gliricidia plants to salinity stress, leaf metabolic and transcription profiles were generated and submitted to single and integrated analyses. RNA from leaf samples were subjected to RNA sequencing using an Illumina HiSeq platform and the paired-end strategy. Polar and lipidic fractions from leaf samples were extracted and analyzed on an ultra-high-performance liquid chromatography (UHPLC) coupled with electrospray ionization quadrupole time-of-flight high-resolution mass spectrometry (MS) system. Acquired data were analyzed using the OmicsBox, XCMS Online, MetaboAnalyst, and Omics Fusion platforms. The substrate salinization protocol used allowed the identification of two distinct responses to salt stress: tolerance and adaptation. Single analysis on transcriptome and metabolome data sets led to a group of 5,672 transcripts and 107 metabolites differentially expressed in gliricidia leaves under salt stress. The phenylpropanoid biosynthesis was the most affected pathway, with 15 metabolites and three genes differentially expressed. Results showed that the differentially expressed metabolites and genes from this pathway affect mainly short-term salt stress (STS). The single analysis of the transcriptome identified 12 genes coding for proteins that might play a role in gliricidia response at both STS and long-term salt stress (LTS). Further studies are needed to reveal the mechanisms behind the adaptation response.


Asunto(s)
Fabaceae , Transcriptoma , Fabaceae/genética , Metabolómica , Salinidad , Estrés Salino/genética , Tolerancia a la Sal/genética
9.
J Proteome Res ; 9(10): 5038-46, 2010 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-20738108

RESUMEN

We have designed an in vitro experimental setup to study the role of sucrose in sugar-mediated acclimation of banana meristems using established highly proliferating meristem cultures. It is a first step toward the systems biology of a meristem and the understanding of how it can survive severe abiotic stress. Using the 2D-DIGE proteomic approach and a meristem-specific EST library, we describe the long-term acclimation response of banana meristems (after 2, 4, 8, and 14 days) and analyze the role of sucrose in this acclimation by setting up a control, a sorbitol, and a sucrose acclimation treatment over time. Sucrose synthase is the dominant enzyme for sucrose breakdown in meristem tissue, which is most likely related to its lower energy consumption. Metabolizing sucrose is of paramount importance to survive, but the uptake of sugar and its metabolism also drive respiration, which may result in limited oxygen levels. According to our data, a successful acclimation is correlated to an initial efficient uptake of sucrose and subsequently a reduced breakdown of sucrose and an induction of fermentation likely by a lack of oxygen.


Asunto(s)
Meristema/metabolismo , Proteínas de Plantas/metabolismo , Proteómica/métodos , Sacarosa/metabolismo , Aclimatación/efectos de los fármacos , Análisis de Varianza , Electroforesis en Gel Bidimensional , Etiquetas de Secuencia Expresada , Espectrometría de Masas , Meristema/efectos de los fármacos , Meristema/fisiología , Musa/efectos de los fármacos , Musa/genética , Musa/metabolismo , Proteínas de Plantas/genética , Análisis de Componente Principal , Regeneración/efectos de los fármacos , Sorbitol/metabolismo , Sorbitol/farmacología , Sacarosa/farmacología , Técnicas de Cultivo de Tejidos
10.
Pathol Oncol Res ; 26(4): 2489-2497, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32583330

RESUMEN

Metastatic renal cell carcinoma (mRCC) encompasses a heterogeneous group of neoplasms with distinct clinical behavior and prognoses. As a result of the increasing number of therapeutic options in the metastatic setting, it is crucial to improve prognostic stratification ability. We aimed to evaluate the prognostic value of neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR) and combination platelet count and neutrophil lymphocyte ratio (COP-NLR) in patients with mRCC. We evaluated a cohort of mRCC patients treated with first-line pazopanib or sunitinib. Levels of NLR, PLR and COP-NLR were measured prior to systemic treatment and evaluated as prognostic predictors. Primary endpoint was overall survival (OS). Data from 276 patients were included, of which 54.7% received first-line pazopanib and 45.3%, sunitinib. Memorial Sloan-Kettering Cancer Center risk classification was intermediate and poor in 50% and 42.6% of patients, respectively. High NLR (> 3.5) was associated with inferior OS (median 9.6 vs 17.8 months, P < 0.001). A high PLR (> 200) was associated with inferior OS (median 10.3 vs 17 months, P = 0.002). The median OS in the COP-NLR 1, 2 and 3 groups were 19.0 months (95% CI 15.3-26.0), 13.1 months (95% CI 9.8-17.0) and 7.4 months (95% CI 3.6-11.9), respectively (P < 0.001). In the multivariate analysis, high NLR and high COP-NLR were associated with inferior OS. Both high NLR and high COP-NLR were associated with poorer OS in our cohort of patients with mRCC treated with first-line pazopanib or sunitinib.


Asunto(s)
Antineoplásicos/uso terapéutico , Biomarcadores de Tumor/sangre , Carcinoma de Células Renales/inmunología , Neoplasias Renales/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Renales/tratamiento farmacológico , Niño , Femenino , Humanos , Indazoles/uso terapéutico , Inflamación/sangre , Neoplasias Renales/tratamiento farmacológico , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Neutrófilos , Recuento de Plaquetas , Pronóstico , Pirimidinas/uso terapéutico , Sulfonamidas/uso terapéutico , Sunitinib/uso terapéutico , Adulto Joven
11.
Ecancermedicalscience ; 13: 973, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31921344

RESUMEN

INTRODUCTION: Non-clear cell renal cell carcinoma (nccRCC) and sarcomatoid renal cell carcinoma (sRCC) are underrepresented in clinical trials. Treatment approaches are frequently extrapolated from data of clear cell renal cell carcinoma, in which pazopanib is non-inferior to sunitinib. We aim to compare the effectiveness of first-line sunitinib and pazopanib for nccRCC and sRCC. METHODS: We evaluated a retrospective cohort of patients with metastatic nccRCC and sRCC treated with first-line sunitinib or pazopanib at an academic cancer centre. Overall survival (OS), progression-free survival (PFS) and response rate were measured. Kaplan-Meier and log-rank analyses were used for time-to-event data. Cox regression was used for prognostic factors. RESULTS: Fifty-three patients were included; 16 (30.1%) treated with sunitinib and 37 (69.9%) with pazopanib. Forty-six (86.8%) patients had nccRCC and 7 (13.2%) had sRCC. The majority had intermediate or poor International Metastatic Renal-Cell Carcinoma Database Consortium risk (93%).Median PFS was 6.6 months with sunitinib and 4.9 months with pazopanib (HR 1.75; P = 0.078). Treatment with pazopanib was associated with inferior OS in comparison with sunitinib (median OS: 30.4 months versus 8.7 months; HR 2.71, 95% CI 1.31-5.58, P = 0.007). These results were confirmed in subgroup analysis of patients with papillary, chromophobe and MiT family translocation histologies (median OS: 38.7 months versus 14.7 months; HR 3.16, 95% CI 1.20-8.29, P = 0.019). Unclassified and sarcomatoid histologies had inferior OS (median: 6.9 and 1.1 months, respectively) regardless of the treatment used. CONCLUSION: In this patient cohort, pazopanib was associated with inferior OS in comparison with sunitinib for metastatic nccRCC. Larger trials are ideally warranted to confirm these results.

12.
BMC Genomics ; 9: 58, 2008 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-18234080

RESUMEN

BACKGROUND: Musa species (Zingiberaceae, Zingiberales) including bananas and plantains are collectively the fourth most important crop in developing countries. Knowledge concerning Musa genome structure and the origin of distinct cultivars has greatly increased over the last few years. Until now, however, no large-scale analyses of Musa genomic sequence have been conducted. This study compares genomic sequence in two Musa species with orthologous regions in the rice genome. RESULTS: We produced 1.4 Mb of Musa sequence from 13 BAC clones, annotated and analyzed them along with 4 previously sequenced BACs. The 443 predicted genes revealed that Zingiberales genes share GC content and distribution characteristics with eudicot and Poaceae genomes. Comparison with rice revealed microsynteny regions that have persisted since the divergence of the Commelinid orders Poales and Zingiberales at least 117 Mya. The previously hypothesized large-scale duplication event in the common ancestor of major cereal lineages within the Poaceae was verified. The divergence time distributions for Musa-Zingiber (Zingiberaceae, Zingiberales) orthologs and paralogs provide strong evidence for a large-scale duplication event in the Musa lineage after its divergence from the Zingiberaceae approximately 61 Mya. Comparisons of genomic regions from M. acuminata and M. balbisiana revealed highly conserved genome structure, and indicated that these genomes diverged circa 4.6 Mya. CONCLUSION: These results point to the utility of comparative analyses between distantly-related monocot species such as rice and Musa for improving our understanding of monocot genome evolution. Sequencing the genome of M. acuminata would provide a strong foundation for comparative genomics in the monocots. In addition a genome sequence would aid genomic and genetic analyses of cultivated Musa polyploid genotypes in research aimed at localizing and cloning genes controlling important agronomic traits for breeding purposes.


Asunto(s)
Genoma de Planta/genética , Musa/clasificación , Musa/genética , Oryza/genética , Sintenía/genética , Arabidopsis/genética , Composición de Base , Cromosomas Artificiales Bacterianos , Elementos Transponibles de ADN/genética , ADN Complementario/genética , Evolución Molecular , Etiquetas de Secuencia Expresada , Duplicación de Gen , Genes de Plantas/genética , Musa/enzimología , Oryza/enzimología , Polimorfismo de Longitud del Fragmento de Restricción , Secuencias Repetitivas de Ácidos Nucleicos/genética , Sorghum/genética , Especificidad de la Especie
13.
BMC Plant Biol ; 8: 15, 2008 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-18234103

RESUMEN

BACKGROUND: Many commercial banana varieties lack sources of resistance to pests and diseases, as a consequence of sterility and narrow genetic background. Fertile wild relatives, by contrast, possess greater variability and represent potential sources of disease resistance genes (R-genes). The largest known family of plant R-genes encode proteins with nucleotide-binding site (NBS) and C-terminal leucine-rich repeat (LRR) domains. Conserved motifs in such genes in diverse plant species offer a means for isolation of candidate genes in banana which may be involved in plant defence. RESULTS: A computational strategy was developed for unbiased conserved motif discovery in NBS and LRR domains in R-genes and homologues in monocotyledonous plant species. Degenerate PCR primers targeting conserved motifs were tested on the wild cultivar Musa acuminata subsp. burmannicoides, var. Calcutta 4, which is resistant to a number of fungal pathogens and nematodes. One hundred and seventy four resistance gene analogs (RGAs) were amplified and assembled into 52 contiguous sequences. Motifs present were typical of the non-TIR NBS-LRR RGA subfamily. A phylogenetic analysis of deduced amino-acid sequences for 33 RGAs with contiguous open reading frames (ORFs), together with RGAs from Arabidopsis thaliana and Oryza sativa, grouped most Musa RGAs within monocotyledon-specific clades. RFLP-RGA markers were developed, with 12 displaying distinct polymorphisms in parentals and F1 progeny of a diploid M. acuminata mapping population. Eighty eight BAC clones were identified in M. acuminata Calcutta 4, M. acuminata Grande Naine, and M. balbisiana Pisang Klutuk Wulung BAC libraries when hybridized to two RGA probes. Multiple copy RGAs were common within BAC clones, potentially representing variation reservoirs for evolution of new R-gene specificities. CONCLUSION: This is the first large scale analysis of NBS-LRR RGAs in M. acuminata Calcutta 4. Contig sequences were deposited in GenBank and assigned numbers ER935972 - ER936023. RGA sequences and isolated BACs are a valuable resource for R-gene discovery, and in future applications will provide insight into the organization and evolution of NBS-LRR R-genes in the Musa A and B genome. The developed RFLP-RGA markers are applicable for genetic map development and marker assisted selection for defined traits such as pest and disease resistance.


Asunto(s)
Genes de Plantas , Musa/genética , Polimorfismo de Longitud del Fragmento de Restricción , Teorema de Bayes , Cartilla de ADN , Musa/clasificación , Filogenia , Polimorfismo Genético
14.
J Glob Oncol ; 4: 1-10, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-30199304

RESUMEN

Purpose Sunitinib and pazopanib are multitargeted tyrosine kinase inhibitors (TKIs) that act against vascular endothelial growth factor receptors and are standard first-line treatment options for metastatic clear cell renal cell carcinoma (ccRCC). The Brazilian public health system diverges from the randomized clinical trials in the availability of first and subsequent lines of treatment and in clinical and demographic characteristics of patients. Therefore, it is essential to describe the history of advanced ccRCC during and after TKI treatment in this population. Methods We performed a retrospective analysis of patients with advanced ccRCC treated with a first-line TKI (either sunitinib or pazopanib) between February 2009 and March 2017 in a single academic Brazilian cancer center (Instituto do Câncer do Estado de São Paulo). Results Of the 222 patients, 109 were treated with sunitinib and 113 with pazopanib. The median duration of treatment and overall survival (OS) were 6.4 and 15.2 months for sunitinib and 6.7 and 14.2 months for pazopanib, respectively. Discontinuation of treatment occurred secondarily to progressive disease or death in 64.2% of patients using sunitinib and in 54.8% of patients using pazopanib. Adverse events were responsible for discontinuation of treatment in 28.4% of patients in the sunitinib group and in 22.1% in the pazopanib group. According to Memorial Sloan-Kettering Cancer Center risk categories, the OS was 32.9 months, 15.9 months, and 8.1 months for low risk, intermediate risk, and poor risk, respectively (hazard ratio, 1.72; 95% CI, 1.13 to 2.26; P < .001). Conclusion The use of TKI inhibitors as first-line treatment of metastatic RCC is effective and feasible in the Brazilian public health. However, the median OS of our population is considerably lower compared with the prospective trials that evaluated the same drugs.


Asunto(s)
Carcinoma de Células Renales/tratamiento farmacológico , Neoplasias Renales/tratamiento farmacológico , Pirimidinas/uso terapéutico , Sulfonamidas/uso terapéutico , Sunitinib/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos/uso terapéutico , Brasil , Carcinoma de Células Renales/secundario , Supervivencia sin Enfermedad , Femenino , Humanos , Indazoles , Neoplasias Renales/patología , Masculino , Persona de Mediana Edad , Inhibidores de Proteínas Quinasas/uso terapéutico , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
15.
Breast ; 38: 39-44, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29223797

RESUMEN

BACKGROUND: and Purpose: Post-operative radiation therapy (PORT) is usually indicated for patients with breast cancer (BC) after neoadjuvant chemotherapy (NAC) and surgery. However, the optimal timing to initiation of PORT is currently unknown. MATERIAL AND METHODS: We retrospectively evaluated data from patients with BC who received PORT after NAC and surgery at our institution from 2008 to 2014. Patients were categorized into three groups according to the time between surgery and PORT: <8 weeks, 8-16 weeks and >16 weeks. RESULTS: A total of 581 patients were included; 74% had clinical stage III. Forty-three patients started PORT within 8 weeks, 354 between 8 and 16 weeks and 184 beyond 16 weeks from surgery. With a median follow-up of 32 months, initiation of PORT up to 8 weeks after surgery was associated with better disease-free survival (DFS) (<8 weeks versus 8-16 weeks: HR 0.33; 95% CI 0.13-0.81; p = 0.02; <8 weeks versus >16 weeks: HR 0.38; 95% CI 0.15-0.96; p = 0.04) and better overall survival (OS) (<8 weeks versus 8-16 weeks: HR 0.22; 95% CI 0.05-0.90; p = 0.036; <8 weeks versus >16 weeks: HR 0.28; 95% CI 0.07-1.15; p = 0.08). CONCLUSION: PORT started up to 8 weeks after surgery was associated with better DFS and OS in locally-advanced BC patients submitted to NAC. Our findings suggest that early initiation of PORT is critically important for these patients. However, the low numbers of patients and events in this study prevent us from drawing firm conclusions.


Asunto(s)
Neoplasias de la Mama/radioterapia , Mastectomía/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/cirugía , Quimioterapia Adyuvante/métodos , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Terapia Neoadyuvante/métodos , Radioterapia Adyuvante/métodos , Estudios Retrospectivos , Tasa de Supervivencia , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
16.
Biotechnol Lett ; 29(1): 79-87, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17016672

RESUMEN

The introduction of anti-apoptotic genes into plants leads to resistance to environmental stress and broad-spectrum disease resistance. The anti-apoptotic gene (p35) from a baculovirus was introduced into the genome of passion fruit plants by biobalistics. Eleven regenerated plants showed the presence of the p35 gene by PCR and/or dot blot hybridization. Transcriptional analysis of regenerated plants showed the presence of specific p35 transcripts in 9 of them. Regenerated plants containing the p35 gene were inoculated with the cowpea aphid-borne mosaic virus (CABMV), the bacterium Xanthomonas axonopodis pv passiflorae, and the herbicide, glufosinate, (Syngenta). None of the plants showed resistance to CABMV. Regenerated plants (p35+) showed less than half of local lesions showed by non-transgenic plants when inoculated with X. axonopodis and some p35+ plants showed increased tolerance to the glufosinate herbicide when compared to non-transgenic plants.


Asunto(s)
Comovirus/fisiología , Mejoramiento Genético/métodos , Resistencia a los Herbicidas/fisiología , Passiflora/fisiología , Passiflora/virología , Enfermedades de las Plantas/genética , Proteínas Virales/metabolismo , Animales , Áfidos/virología , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Passiflora/microbiología , Proteínas Virales/genética
17.
Plant Methods ; 13: 61, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28769996

RESUMEN

BACKGROUND: Photosynthesis can be roughly separated into biochemical and photochemical processes. Both are affected by drought and can be assessed by non-invasive standard methods. Gas exchange, which mainly assesses the first process, has well-defined protocols. It is considered a standard method for evaluation of plant responses to drought. Under such stress, assessment of photochemical apparatus by chlorophyll fluorescence needs improvement to become faster and reproducible, especially in growing plants under field conditions. For this, we developed a protocol based on chlorophyll fluorescence imaging, using a rapid light curve approach. RESULTS: Almost all parameters obtained by rapid light curves have shown statistical differences between control and drought stressed maize plants. However, most of them were affected by induction processes, relaxation rate, and/or differences in chlorophyll content; while they all were influenced by actinic light intensity on each light step of light curve. Only the normalized parameters related to photochemical and non-photochemical quenching were strongly correlated with data obtained by gas exchange, but only from the light step in which the linear electron flow reached saturation. CONCLUSIONS: The procedure developed in this study for discrimination of plant responses to water deficit stress proved to be as fast, efficient and reliable as the standard technique of gas exchange in order to discriminate the responses of maize genotypes to drought. However, unlike that, there is no need to perform daily and time consuming calibration routines. Moreover, plant acclimation to the dark is not required. The protocol can be applied to plants growing in both controlled conditions and full sunlight in the field. In addition, it generates parameters in a fast and accurate measurement process, which enables evaluating several plants in a short period of time.

18.
Appl Radiat Isot ; 57(3): 375-80, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12201145

RESUMEN

The application of sewage sludge as a fertilizer on soils may cause compacted surface layers (surface sealing), which can promote changes on soil physical properties. The objective of this work was to study the use of gamma-ray computed tomography, as a diagnostic tool for the evaluation of this sealing process through the measurement of soil bulk density distribution of the soil surface layer of samples subjected to sewage sludge application. Tomographic images were taken with a first generation tomograph with a resolution of 1 mm. The image analysis opened the possibility to obtain soil bulk density profiles and average soil bulk densities of the surface layer and to detect the presence of soil surface sealing. The sealing crust thickness was estimated to be in the range of 2-4 mm.

19.
Appl Radiat Isot ; 59(1): 17-25, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12878118

RESUMEN

Soil compaction is one of the fundamental parameters to evaluate the environmental impact of agricultural machinery traffic on soils. Compaction causes modifications on soil physical properties such as changes in porosity and structure that are related to soil water movement and gas exchange The objective of this work was to evaluate soil surface sealing after sewage-sludge application, and the influence of agricultural machinery traffic, through computed tomography. A first generation tomograph was used having a 137Cs source and a 3 in x 3 in NaI(Tl) scintillation crystal detector coupled to a photomultiplier tube. Image analysis and tomographic unit profiles could successfully be used for the detection of soil surface sealing and soil compaction due to machinery traffic associated to sewage-sludge application.


Asunto(s)
Rayos gamma , Aguas del Alcantarillado/química , Suelo/análisis , Tomografía Computarizada de Emisión/métodos , Agricultura , Radioisótopos de Cesio , Procesamiento de Imagen Asistido por Computador
20.
Genomics Insights ; 7: 13-22, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-26203259

RESUMEN

Aiming at generating a comprehensive genomic database on Elaeis spp., our group is leading several R&D initiatives with Elaeis guineensis (African oil palm) and Elaeis oleifera (American oil palm), including the whole-genome sequencing of the last. Genome size estimates currently available for this genus are controversial, as they indicate that American oil palm genome is about half the size of the African oil palm genome and that the genome of the interspecific hybrid is bigger than both the parental species genomes. We estimated the genome size of three E. guineensis genotypes, five E. oleifera genotypes, and two interspecific hybrids genotypes. On average, the genome size of E. guineensis is 4.32 ± 0.173 pg, while that of E. oleifera is 4.43 ± 0.018 pg. This indicates that both genomes are similar in size, even though E. oleifera is in fact bigger. As expected, the hybrid genome size is around the average of the two genomes, 4.40 ± 0.016 pg. Additionally, we demonstrate that both species present around 38% of GC content. As our results contradict the currently available data on Elaeis spp. genome sizes, we propose that the actual genome size of the Elaeis species is around 4 pg and that American oil palm possesses a larger genome than African oil palm.

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