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1.
Environ Sci Technol ; 56(21): 14982-14993, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-35759608

RESUMEN

Wastewater-based surveillance (WBS) for disease monitoring is highly promising but requires consistent methodologies that incorporate predetermined objectives, targets, and metrics. Herein, we describe a comprehensive metagenomics-based approach for global surveillance of antibiotic resistance in sewage that enables assessment of 1) which antibiotic resistance genes (ARGs) are shared across regions/communities; 2) which ARGs are discriminatory; and 3) factors associated with overall trends in ARGs, such as antibiotic concentrations. Across an internationally sourced transect of sewage samples collected using a centralized, standardized protocol, ARG relative abundances (16S rRNA gene-normalized) were highest in Hong Kong and India and lowest in Sweden and Switzerland, reflecting national policy, measured antibiotic concentrations, and metal resistance genes. Asian versus European/US resistomes were distinct, with macrolide-lincosamide-streptogramin, phenicol, quinolone, and tetracycline versus multidrug resistance ARGs being discriminatory, respectively. Regional trends in measured antibiotic concentrations differed from trends expected from public sales data. This could reflect unaccounted uses, captured only by the WBS approach. If properly benchmarked, antibiotic WBS might complement public sales and consumption statistics in the future. The WBS approach defined herein demonstrates multisite comparability and sensitivity to local/regional factors.


Asunto(s)
Aguas del Alcantarillado , Aguas Residuales , ARN Ribosómico 16S/genética , Genes Bacterianos , Antibacterianos/farmacología
2.
Am J Nephrol ; 52(2): 85-97, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33735856

RESUMEN

BACKGROUND: Recent studies have identified the combination of vancomycin with piperacillin-tazobactam (VPT) to be associated with increased nephrotoxicity. Multiple, large cohort studies have found this widely used combination to have a higher risk of nephrotoxicity than other regimens in a variety of populations. SUMMARY: This review summarizes the epidemiology and clinical features of VPT-associated acute kidney injury (AKI). Potential mechanisms involved in the pathogenesis of this phenomenon are also discussed. Key Message: VPT-associated nephrotoxicity is a recently recognized clinical entity. Clinical strategies to minimize the risk of toxicity in this setting include antimicrobial stewardship, monitoring of kidney function, and emerging data supporting the potential role for novel biomarkers in predicting and managing AKI.


Asunto(s)
Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/complicaciones , Antibacterianos/efectos adversos , Combinación Piperacilina y Tazobactam/efectos adversos , Vancomicina/efectos adversos , Lesión Renal Aguda/epidemiología , Antibacterianos/administración & dosificación , Programas de Optimización del Uso de los Antimicrobianos , Creatinina/metabolismo , Enfermedad Crítica , Quimioterapia Combinada/efectos adversos , Humanos , Túbulos Renales/metabolismo , Nefritis/inducido químicamente , Nefritis/inmunología , Gravedad del Paciente , Combinación Piperacilina y Tazobactam/administración & dosificación , Factores de Riesgo , Vancomicina/administración & dosificación
3.
Theor Appl Genet ; 134(8): 2379-2398, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34128089

RESUMEN

KEY MESSAGE: Methyl esterase (MES), PvMES1, contributes to the defense response toward Fusarium wilt in common beans by regulating the salicylic acid (SA) mediated signaling pathway from phenylpropanoid synthesis and sugar metabolism as well as others. Common bean (Phaseolus vulgaris L.) is an important food legume. Fusarium wilt caused by Fusarium oxysporum f. sp. phaseoli is one of the most serious soil-borne diseases of common bean found throughout the world and affects the yield and quality of the crop. Few sources of Fusarium wilt resistance exist in legumes and most are of quantitative inheritance. In this study, we have identified a methyl esterase (MES), PvMES1, that contributes to plant defense response by regulating the salicylic acid (SA) mediated signaling pathway in response to Fusarium wilt in common beans. The result showed the role of PvMES1 in regulating SA levels in common bean and thus the SA signaling pathway and defense response mechanism in the plant. Overexpression of the PvMES1 gene enhanced Fusarium wilt resistance; while silencing of the gene caused susceptibility to the diseases. RNA-seq analysis with these transiently modified plants showed that genes related to SA level changes included the following gene ontologies: (a) phenylpropanoid synthesis; (b) sugar metabolism; and (c) interaction between host and pathogen as well as others. These key signal elements activated the defense response pathway in common bean to Fusarium wilt. Collectively, our findings indicate that PvMES1 plays a pivotal role in regulating SA biosynthesis and signaling, and increasing Fusarium wilt resistance in common bean, thus providing novel insight into the practical applications of both SA and MES genes and pathways they contribute to for developing elite crop varieties with enhanced broad-spectrum resistance to this critical disease.


Asunto(s)
Resistencia a la Enfermedad/inmunología , Fusarium/fisiología , Oxidorreductasas O-Demetilantes/metabolismo , Phaseolus/inmunología , Enfermedades de las Plantas/inmunología , Proteínas de Plantas/metabolismo , Ácido Salicílico/metabolismo , Resistencia a la Enfermedad/genética , Regulación de la Expresión Génica de las Plantas , Oxidorreductasas O-Demetilantes/genética , Phaseolus/genética , Phaseolus/crecimiento & desarrollo , Phaseolus/microbiología , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Proteínas de Plantas/genética , Transducción de Señal
4.
Environ Sci Technol ; 55(6): 3775-3785, 2021 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-33645970

RESUMEN

Maria made a landfall in Puerto Rico on September 20, 2017 as a category 4 hurricane, causing severe flooding, widespread electricity outages, damage to infrastructure, and interruptions in water and wastewater treatment. Small rural community water systems face unique challenges in providing drinking water, which intensify after natural disasters. The purpose of this study was to evaluate the functionality of six very small rural public water systems and one large regulated system in Puerto Rico six months after Maria and survey a broad sweep of fecal, zoonotic, and opportunistic pathogens from the source to tap. Samples were collected from surface and groundwater sources, after water treatment and after distribution to households. Genes indicative of pathogenic Leptospira spp. were detected by polymerase chain reaction (PCR) in all systems reliant on surface water sources. Salmonella spp. was detected in surface and groundwater sources and some distribution system water both by culture and PCR. Legionella spp. and Mycobacteria spp. gene numbers measured by quantitative PCR were similar to nonoutbreak conditions in the continental U.S. Amplicon sequencing provided a nontarget screen for other potential pathogens of concern. This study aids in improving future preparedness, assessment, and recovery operations for small rural water systems after natural disasters.


Asunto(s)
Tormentas Ciclónicas , Agua Potable , Humanos , Puerto Rico , Población Rural , Calidad del Agua
5.
Theor Appl Genet ; 131(8): 1645-1658, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29752522

RESUMEN

KEY MESSAGE: Twelve meta-QTL for seed Fe and Zn concentration and/or content were identified from 87 QTL originating from seven population grown in sixteen field trials. These meta-QTL include 2 specific to iron, 2 specific to zinc and 8 that co-localize for iron and zinc concentrations and/or content. Common bean (Phaseolus vulgaris L.) is the most important legume for human consumption worldwide and it is an important source of microelements, especially iron and zinc. Bean biofortification breeding programs develop new varieties with high levels of Fe and Zn targeted for countries with human micronutrient deficiencies. Biofortification efforts thus far have relied on phenotypic selection of raw seed mineral concentrations in advanced generations. While numerous quantitative trait loci (QTL) studies have been conducted to identify genomic regions associated with increased Fe and Zn concentration in seeds, these results have yet to be employed for marker-assisted breeding. The objective of this study was to conduct a meta-analysis from seven QTL studies in Andean and Middle American intra- and inter-gene pool populations to identify the regions in the genome that control the Fe and Zn levels in seeds. Two meta-QTL specific to Fe and two meta-QTL specific to Zn were identified. Additionally, eight Meta QTL that co-localized for Fe and Zn concentration and/or content were identified across seven chromosomes. The Fe and Zn shared meta-QTL could be useful candidates for marker-assisted breeding to simultaneously increase seed Fe and Zn. The physical positions for 12 individual meta-QTL were identified and within five of the meta-QTL, candidate genes were identified from six gene families that have been associated with transport of iron and zinc in plants.


Asunto(s)
Hierro/análisis , Phaseolus/genética , Sitios de Carácter Cuantitativo , Semillas/química , Zinc/análisis , Mapeo Cromosómico , Pool de Genes , Fenotipo , Fitomejoramiento
6.
Genet Mol Biol ; 40(1): 109-122, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28222201

RESUMEN

Angular leaf spot (ALS) and powdery mildew (PWM) are two important fungi diseases causing significant yield losses in common beans. In this study, a new genetic linkage map was constructed using single sequence repeats (SSRs) and single nucleotide polymorphisms (SNPs), in a segregating population derived from the AND 277 x SEA 5 cross, with 105 recombinant inbred lines. Phenotypic evaluations were performed in the greenhouse to identify quantitative trait loci (QTLs) associated with resistance by means of the composite interval mapping analysis. Four QTLs were identified for ALS resistance. The QTL ALS11AS, linked on the SNP BAR 5054, mapped on chromosome Pv11, showed the greatest effect (R2 = 26.5%) on ALS phenotypic variance. For PWM resistance, two QTLs were detected, PWM2AS and PWM11AS, on Pv2 and Pv11, explaining 7% and 66% of the phenotypic variation, respectively. Both QTLs on Pv11 were mapped on the same genomic region, suggesting that it is a pleiotropic region. The present study resulted in the identification of new markers closely linked to ALS and PWM QTLs, which can be used for marker-assisted selection, fine mapping and positional cloning.

7.
Genet Mol Biol ; 40(4): 813-823, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29064511

RESUMEN

The common bean is characterized by high sensitivity to drought and low productivity. Breeding for drought resistance in this species involves genes of different genetic groups. In this work, we used a SEA 5 x AND 277 cross to map quantitative trait loci associated with drought tolerance in order to assess the factors that determine the magnitude of drought response in common beans. A total of 438 polymorphic markers were used to genotype the F8 mapping population. Phenotyping was done in two greenhouses, one used to simulate drought and the other to simulate irrigated conditions. Fourteen traits associated with drought tolerance were measured to identify the quantitative trait loci (QTLs). The map was constructed with 331 markers that covered all 11 chromosomes and had a total length of 1515 cM. Twenty-two QTLs were discovered for chlorophyll, leaf and stem fresh biomass, leaf biomass dry weight, leaf temperature, number of pods per plant, number of seeds per plant, seed weight, days to flowering, dry pod weight and total yield under well-watered and drought (stress) conditions. All the QTLs detected under drought conditions showed positive effects of the SEA 5 allele. This study provides a better understanding of the genetic inheritance of drought tolerance in common bean.

8.
Genes (Basel) ; 15(3)2024 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-38540421

RESUMEN

Cowpea (Vigna unguiculata L. Walp) is an important grain legume crop of the subtropics, particularly in West Africa, where it contributes to the livelihoods of small-scale farmers. Despite being a drought-resilient crop, cowpea production is hampered by insect pests, diseases, parasitic weeds, and various abiotic stresses. Genetic improvement can help overcome these limitations, and exploring diverse cowpea genetic resources is crucial for cowpea breeding. This study evaluated the genetic diversity of 361 cowpea accessions from the USDA core collection for the species using 102 Kompetitive Allele Specific PCR (KASP) single nucleotide polymorphism (SNP) markers. A total of 102 KASP-SNP was validated in the germplasm panel, and 72 showed polymorphism across the germplasm panel. The polymorphism information content (PIC) of all SNPs ranged from 0.1 to 0.37, with an average of 0.29, while the mean observed heterozygosity was 0.52. The population structure revealed three distinct populations that clustered into two major groups after phylogenetic analysis. Analysis of molecular variance (AMOVA) indicated greater genetic variation within populations than among populations. Although cowpea generally has a narrow genetic diversity, the accessions used in this study exhibited considerable variation across geographical regions, sub-species, and improvement status. These results indicated that the selected KASP genotyping assay can provide robust and accurate genotyping data for application in the selection and management of cowpea germplasm in breeding programs and genebanks.


Asunto(s)
Vigna , Estados Unidos , Vigna/genética , Filogenia , Polimorfismo de Nucleótido Simple/genética , Alelos , United States Department of Agriculture , Fitomejoramiento , Reacción en Cadena de la Polimerasa
9.
Theor Appl Genet ; 126(2): 535-48, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23124389

RESUMEN

Single nucleotide polymorphism (SNP) detection has become a marker system of choice, because of the high abundance of source polymorphisms and the ease with which allele calls are automated. Various technologies exist for the evaluation of SNP loci and previously we validated two medium throughput technologies. In this study, our goal was to utilize a 768 feature, Illumina GoldenGate assay for common bean (Phaseolus vulgaris L.) developed from conserved legume gene sequences and to use the new technology for (1) the evaluation of parental polymorphisms in a mini-core set of common bean accessions and (2) the analysis of genetic diversity in the crop. A total of 736 SNPs were scored on 236 diverse common bean genotypes with the GoldenGate array. Missing data and heterozygosity levels were low and 94 % of the SNPs were scorable. With the evaluation of the parental polymorphism genotypes, we estimated the utility of the SNP markers in mapping for inter-genepool and intra-genepool populations, the latter being of lower polymorphism than the former. When we performed the diversity analysis with the diverse genotypes, we found Illumina GoldenGate SNPs to provide equivalent evaluations as previous gene-based SNP markers, but less fine-distinctions than with previous microsatellite marker analysis. We did find, however, that the gene-based SNPs in the GoldenGate array had some utility in race structure analysis despite the low polymorphism. Furthermore the SNPs detected high heterozygosity in wild accessions which was probably a reflection of ascertainment bias. The Illumina SNPs were shown to be effective in distinguishing between the genepools, and therefore were most useful in saturation of inter-genepool genetic maps. The implications of these results for breeding in common bean are discussed as well as the advantages and disadvantages of the GoldenGate system for SNP detection.


Asunto(s)
Genes de Plantas/genética , Marcadores Genéticos , Ensayos Analíticos de Alto Rendimiento , Phaseolus/genética , Polimorfismo de Nucleótido Simple/genética , Mapeo Cromosómico , ADN de Plantas/genética , Genoma de Planta , Genotipo , Reacción en Cadena de la Polimerasa
10.
Phytopathology ; 103(2): 156-68, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23294404

RESUMEN

Common bean production is constrained by many fungal, viral, and bacterial pathogens. Thus, the identification of resistance (R) genes is an important focal point of common bean research. The main goal of our study was to identify resistance gene homologues (RGH) in the crop, using degenerate primers designed from conserved sequences in the nucleotide-binding site (NBS) domains of R-genes from the model legume Medicago truncatula. Total DNA of the Andean common bean genotype G19833 was used for amplification of over 500 primer combinations. Sequencing of amplicons showed that 403 cloned fragments had uninterrupted open reading frames and were considered representative of functional RGH genes. The sequences were grouped at two levels of nucleotide identity (90 and 80%) and representative sequences of each group were used for phylogenetic analyses. The RGH sequence diversity of common bean was divided into TIR and non-TIR families, each with different clusters. The TIR sequences grouped into 14 clades while non-TIR sequences grouped into seven clades. Pairwise comparisons showed purifying selection, although some sequences may have been the result of diversifying selection. Knowledge about RGH genes in common bean can allow the design of molecular markers for pyramiding of resistance genes against various pathogens.


Asunto(s)
Resistencia a la Enfermedad/genética , Genes de Plantas/genética , Phaseolus/genética , Enfermedades de las Plantas/inmunología , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Secuencia de Bases , Sitios de Unión/genética , Secuencia Conservada , Cartilla de ADN/genética , ADN de Plantas/química , ADN de Plantas/genética , Datos de Secuencia Molecular , Phaseolus/inmunología , Filogenia , Enfermedades de las Plantas/microbiología , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN
11.
Int J Sports Physiol Perform ; 18(9): 901-908, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-36410336

RESUMEN

PURPOSE: To examine the effect of match schedule on self-reported wellness and sleep in rugby union referees during the 2019 Rugby World Cup. METHODS: Following an observational design, 18 international-level male referees participating in the 2019 Rugby World Cup completed a daily questionnaire to quantify wellness status (sleep quality, mood, stress, fatigue, muscle soreness, and total wellness) and sleep characteristics (bedtime, wake-up time, and time in bed) from the previous night across the tournament. Linear mixed models and effect sizes (Hedges gav) assessed differences in wellness and sleep characteristics between prematch and postmatch days surrounding single-game and 2-game congested match schedules (prematch1, postmatch1, prematch2, and postmatch2 days). RESULTS: During regular schedules, all self-reported wellness variables except stress were reduced (gav = 0.33-1.05, mean difference -0.32 to -1.21 arbitrary units [AU]) and referees went to bed later (1.08, 1:07 h:min) and spent less time in bed (-0.78, 00:55 h:min) postmatch compared with prematch days. During congested schedules, only wellness variables differed across days, with total wellness reduced on postmatch1 (-0.88, -3.56 AU) and postmatch2 (-0.67, -2.70 AU) days, as well as mood (-1.01, -0.56 AU) and fatigue (-0.90, -1.11 AU) reduced on postmatch1 days compared with prematch days. CONCLUSION: Referees were susceptible to acute reductions in wellness on days following matches regardless of schedule. However, only single-game regular match schedules negatively impacted the sleep characteristics of referees. Targeted strategies to maximize wellness status and sleep opportunities in referees considering the match schedule faced should be explored during future Rugby World Cup competitions.


Asunto(s)
Rugby , Humanos , Masculino , Fatiga , Autoinforme , Sueño
12.
Front Plant Sci ; 14: 1144681, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37035062

RESUMEN

Grain amaranths are made up of three New World species of pseudo-cereals with C4 photosynthesis from the dicotyledonous family Amaranthaceae and the genus Amaranthus. They originate in two ecoregions of the Americas, namely, the inter-Andean valleys of South America and the volcanic axis and lowlands of Mexico and Central America. These correspond to two centers of domestications for Andean and Mesoamerican crops, with one cultivated species found in the first region and two found in the latter region. To date, no core collection has been made for the grain amaranths in the United States Department of Agriculture (USDA) germplasm system. In this study, our objective was to create a core for the 2,899 gene bank accessions with collection site data by town or farm site of which 1,090 have current geo-referencing of latitude and longitude coordinates. We constituted the core with 260 genotypes of Amaranthus, which we evaluated with 90 single-nucleotide polymorphism markers. Our goal was to distinguish between Andean and Mesoamerican gene pools of amaranths, including the cultivated species and three possible progenitor or wild relative ancestors along with two more species in an outgroup. Population structure, clustering, and discriminant analysis for principal components showed that Andean species Amaranthus caudatus and Amaranthus quitensis shared fewer alleles with Mesoamerican species Amaranthus cruentus and Amaranthus hypochondriacus, compared to each group individually. Amaranthus hybridus was a bridge species that shared alleles with both regions. Molecular markers have the advantage over morphological traits at quickly distinguishing the Andean and Mesoamerican cultivars and have the added benefit of being useful for following inter-species crosses and introgression.

13.
Theor Appl Genet ; 125(5): 1015-31, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22718301

RESUMEN

Iron deficiency anemia and zinc deficiency are major health concerns across the world and can be addressed by biofortification breeding of higher mineral concentration in staple crops, such as common bean. Wild common beans have for the most part had higher average seed mineral concentration than cultivars of this species but have small un-commercial seeds. A logical approach for the transfer of the seed mineral trait from wild beans to cultivated beans is through the advanced backcross breeding approach. The goal of this study was to analyze a population of 138 BC(2)F(3:5) introgression lines derived from the very high iron wild genotype G10022 backcrossed into the genetic background of the commercial-type variety 'Cerinza', a large-red seeded bush bean cultivar of the Andean genepool. In addition to measuring seed mineral accumulation traits and the quantitative trait loci (QTL) controlling these traits we were interested in simultaneously testing the adaptation of the introgression lines in two replicated yield trials. We found the cross to have high polymorphism and constructed an anchored microsatellite map for the population that was 1,554-cM long and covered all 11 linkage groups of the common bean genome. Through composite interval mapping (CIM) and single point analysis (SPA), we identified associations of markers and mineral traits on b01, b06, b07, b08, b10 and b11 for seed iron concentration, and markers on b01, b04 and b10 for seed zinc concentration. The b07 and b08 QTL aligned with previous QTL for iron concentration. A large number of QTL were found for seed weight (9 with CIM and 36 with SPA analysis) and correlations between seed size and mineral content affected the identification of iron and zinc contents' QTL on many linkage groups. Segregation distortion around domestication genes made some areas difficult to introgress. However, in conclusion, the advanced backcross program produced some introgression lines with high mineral accumulation traits using a wild donor parent.


Asunto(s)
Mapeo Cromosómico , Endogamia , Hierro/metabolismo , Phaseolus/genética , Sitios de Carácter Cuantitativo/genética , Semillas/genética , Zinc/metabolismo , Cromosomas de las Plantas/genética , Pool de Genes , Repeticiones de Microsatélite/genética , Estado Nutricional , Phaseolus/crecimiento & desarrollo , Phaseolus/metabolismo , Semillas/metabolismo
14.
Theor Appl Genet ; 125(6): 1137-47, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22678667

RESUMEN

Tepary bean (Phaseolus acutifolius A. Gray) is a dry-land crop species that originated in the deserts of Mexico and the south-western United States and therefore is proposed as a source of drought and salt tolerance for related species and for production in marginal rainfall areas. Few genetic tools have been developed or tested for tepary bean but microsatellites from common bean are an obvious choice for diversity analysis in the crop. The first goal of this study was to validate a set of gene-derived and non-gene simple sequence repeat or microsatellite markers from common bean in tepary bean cultivars and wild relative accessions. The second and more extensive objective of this study was to evaluate the genetic diversity and population structure of the tepary bean accessions to determine if leaf-morphology variants are valid as separate sub-groups of wild tepary beans; if P. parvifolius exist as a separate variants or species; and if cultivated tepary beans originated from one domestication event or several events. Our analysis of 140 tepary bean genotypes showed that a single domestication was likely as the cultivars were most closely related to accessions from Sinaloa and northern Mexico and that diversity was much higher in the wild genotypes compared to the cultivated ones. Other results were that P. parvifolius was classified as a separate species by population structure analysis while the variants P. acutifolius var. acutifolius and var. tenuifolius were admixed and inter-crossed. P. latifolius is not a valid species or variant of P. acutifolius but represents a group of cultivars within tepary bean. This is the first analysis of microsatellite diversity in tepary beans and has implications for breeding and conservation of this crop and its wild relatives.


Asunto(s)
Variación Genética , Repeticiones de Microsatélite , Phaseolus/clasificación , Phaseolus/genética , Alelos , Cruzamiento , Cruzamientos Genéticos , Sequías , Marcadores Genéticos , Genotipo , México , Polimorfismo Genético
15.
Theor Appl Genet ; 125(5): 1069-85, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22772725

RESUMEN

Common beans are an important food legume faced with a series of abiotic stresses the most severe of which is drought. The crop is interesting as a model for the analysis of gene phylogenies due to its domestication process, race structure, and origins in a group of wild common beans found along the South American Andes and the region of Mesoamerica. Meanwhile, the DREB2 transcription factors have been implicated in controlling non-ABA dependent responses to drought stress. With this in mind our objective was to study in depth the genetic diversity for two DREB2 genes as possible candidates for association with drought tolerance through a gene phylogenetic analysis. In this genetic diversity assessment, we analyzed nucleotide diversity at the two candidate genes Dreb2A and Dreb2B, in partial core collections of 104 wild and 297 cultivated common beans with a total of 401 common bean genotypes from world-wide germplasm analyzed. Our wild population sample covered a range of semi-mesic to very dry habitats, while our cultivated samples presented a wide spectrum of low to high drought tolerance. Both genes showed very different patterns of nucleotide variation. Dreb2B exhibited very low nucleotide diversity relative to neutral reference loci previously surveyed in these populations. This suggests that strong purifying selection has been acting on this gene. In contrast, Dreb2A exhibited higher levels of nucleotide diversity, which is indicative of adaptive selection and population expansion. These patterns were more distinct in wild compared to cultivated common beans. These approximations suggested the importance of Dreb2 genes in the context of drought tolerance, and constitute the first steps towards an association study between genetic polymorphism of this gene family and variation in drought tolerance traits. We discuss the utility of allele mining in the DREB gene family for the discovery of new drought tolerance traits from wild common bean.


Asunto(s)
Adaptación Fisiológica/genética , Sequías , Genes de Plantas/genética , Marcadores Genéticos , Phaseolus/genética , Polimorfismo Genético/genética , ADN de Plantas/genética , Haplotipos/genética , Phaseolus/crecimiento & desarrollo , Reacción en Cadena de la Polimerasa
16.
BMC Genet ; 13: 58, 2012 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-22799462

RESUMEN

BACKGROUND: The abscisic acid (ABA) pathway plays an important role in the plants' reaction to drought stress and ABA-stress response (Asr) genes are important in controlling this process. In this sense, we accessed nucleotide diversity at two candidate genes for drought tolerance (Asr1 and Asr2), involved in an ABA signaling pathway, in the reference collection of cultivated common bean (Phaseolus vulgaris L.) and a core collection of wild common bean accessions. RESULTS: Our wild population samples covered a range of mesic (semi-arid) to very dry (desert) habitats, while our cultivated samples presented a wide spectrum of drought tolerance. Both genes showed very different patterns of nucleotide variation. Asr1 exhibited very low nucleotide diversity relative to the neutral reference loci that were previously surveyed in these populations. This suggests that strong purifying selection has been acting on this gene. In contrast, Asr2 exhibited higher levels of nucleotide diversity, which is indicative of adaptive selection. These patterns were more notable in wild beans than in cultivated common beans indicting that natural selection has played a role over long time periods compared to farmer selection since domestication. CONCLUSIONS: Together these results suggested the importance of Asr1 in the context of drought tolerance, and constitute the first steps towards an association study between genetic polymorphism of this gene family and variation in drought tolerance traits. Furthermore, one of our major successes was to find that wild common bean is a reservoir of genetic variation and selection signatures at Asr genes, which may be useful for breeding drought tolerance in cultivated common bean.


Asunto(s)
Sequías , Genes de Plantas , Phaseolus/genética , Polimorfismo Genético , Ecología
17.
BMC Genet ; 13: 48, 2012 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-22734675

RESUMEN

BACKGROUND: In common bean, expressed sequence tags (ESTs) are an underestimated source of gene-based markers such as insertion-deletions (Indels) or single-nucleotide polymorphisms (SNPs). However, due to the nature of these conserved sequences, detection of markers is difficult and portrays low levels of polymorphism. Therefore, development of intron-spanning EST-SNP markers can be a valuable resource for genetic experiments such as genetic mapping and association studies. RESULTS: In this study, a total of 313 new gene-based markers were developed at target genes. Intronic variation was deeply explored in order to capture more polymorphism. Introns were putatively identified after comparing the common bean ESTs with the soybean genome, and the primers were designed over intron-flanking regions. The intronic regions were evaluated for parental polymorphisms using the single strand conformational polymorphism (SSCP) technique and Sequenom MassARRAY system. A total of 53 new marker loci were placed on an integrated molecular map in the DOR364 × G19833 recombinant inbred line (RIL) population. The new linkage map was used to build a consensus map, merging the linkage maps of the BAT93 × JALO EEP558 and DOR364 × BAT477 populations. A total of 1,060 markers were mapped, with a total map length of 2,041 cM across 11 linkage groups. As a second application of the generated resource, a diversity panel with 93 genotypes was evaluated with 173 SNP markers using the MassARRAY-platform and KASPar technology. These results were coupled with previous SSR evaluations and drought tolerance assays carried out on the same individuals. This agglomerative dataset was examined, in order to discover marker-trait associations, using general linear model (GLM) and mixed linear model (MLM). Some significant associations with yield components were identified, and were consistent with previous findings. CONCLUSIONS: In short, this study illustrates the power of intron-based markers for linkage and association mapping in common bean. The utility of these markers is discussed in relation with the usefulness of microsatellites, the molecular markers by excellence in this crop.


Asunto(s)
Mapeo Cromosómico , Fabaceae/genética , Intrones , Polimorfismo de Nucleótido Simple , Etiquetas de Secuencia Expresada , Estudios de Asociación Genética , Ligamiento Genético , Marcadores Genéticos , Repeticiones de Microsatélite
18.
Front Genet ; 13: 910386, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35991553

RESUMEN

Leveraging innovative tools to speed up prebreeding and discovery of genotypic sources of adaptation from landraces, crop wild relatives, and orphan crops is a key prerequisite to accelerate genetic gain of abiotic stress tolerance in annual crops such as legumes and cereals, many of which are still orphan species despite advances in major row crops. Here, we review a novel, interdisciplinary approach to combine ecological climate data with evolutionary genomics under the paradigm of a new field of study: genome-environment associations (GEAs). We first exemplify how GEA utilizes in situ georeferencing from genotypically characterized, gene bank accessions to pinpoint genomic signatures of natural selection. We later discuss the necessity to update the current GEA models to predict both regional- and local- or micro-habitat-based adaptation with mechanistic ecophysiological climate indices and cutting-edge GWAS-type genetic association models. Furthermore, to account for polygenic evolutionary adaptation, we encourage the community to start gathering genomic estimated adaptive values (GEAVs) for genomic prediction (GP) and multi-dimensional machine learning (ML) models. The latter two should ideally be weighted by de novo GWAS-based GEA estimates and optimized for a scalable marker subset. We end the review by envisioning avenues to make adaptation inferences more robust through the merging of high-resolution data sources, such as environmental remote sensing and summary statistics of the genomic site frequency spectrum, with the epigenetic molecular functionality responsible for plastic inheritance in the wild. Ultimately, we believe that coupling evolutionary adaptive predictions with innovations in ecological genomics such as GEA will help capture hidden genetic adaptations to abiotic stresses based on crop germplasm resources to assist responses to climate change. "I shall endeavor to find out how nature's forces act upon one another, and in what manner the geographic environment exerts its influence on animals and plants. In short, I must find out about the harmony in nature" Alexander von Humboldt-Letter to Karl Freiesleben, June 1799.

19.
Mol Hortic ; 2(1): 8, 2022 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-37789473

RESUMEN

The species Vigna unguiculata L. (Walp), commonly known as cowpea, is a multi-purpose legume that has been selected into three subspecies that are divided into grain, fodder and pod (yardlong bean) types. However, genetic bases for distinctions are not well understood. The purpose of this study was to apply genotyping-by-sequencing (GBS) and current reference genome for V. unguiculata to distinguish three subspecies and identify signatures of divergence. The collection of 130 accessions included 128 cultivated from: 1) ssp. cylindrica, fodder type; 2) ssp. sesquipedalis, pod vegetable type; and 3) ssp. unguiculata, grain type. Two wilds genotypes from spp. dekindtiana and spp. pubescens, were used to anchor phylogeny. A total of 11,083 highly informative single nucleotide polymorphisms (SNPs) were discovered. Wild accessions showed distinct genetic fingerprints and were separated from cultivated subspecies. Principal component analysis showed closer relationship between ssp. unguiculata and ssp. cylindrica compared to ssp. sesquipedalis. Relative differentiation of cultivated subspecies (with Fixation Index, FST) indicated the existence of discrete signatures of selection. This work clarifies the population structure, phylogeny, and domestication of cultivated cowpeas. Furthermore, significant genetic differences between grain and pod vegetable types can provide valuable information for future breeding in three cowpea groups.

20.
HRB Open Res ; 5: 31, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36101871

RESUMEN

Background: The aim of this study was to measure the impact of post-acute sequelae of COVID-19 (PASC) on quality of life, mental health, ability to work and return to baseline health in an Irish cohort. Methods: We invited individuals with symptoms of COVID-19 lasting more than 14 days to participate in an anonymous online questionnaire. Basic demographic data and self-reported symptoms were recorded. Internationally validated instruments including the patient health questionnaire somatic, anxiety and depressive symptom scales (PHQ-SADS), the Patient Health Questionnaire-15 (PHQ-15) and Chadler fatigue scale (CFQ) were used. Results: We analysed responses from 988 participants with self-reported confirmed (diagnostic/antibody positive; 81%) or suspected (diagnostic/antibody negative or untested; 9%) COVID-19. The majority of respondents were female (88%), white (98%), with a median age of 43.0 (range 15 - 88 years old) and a median BMI of 26.0 (range 16 - 60). At the time of completing this survey, 89% of respondents reported that they have not returned to their pre-COVID-19 level of health. The median number of symptoms reported was 8 (range 0 to 33 symptoms), with a median duration of 12 months (range 1 to 20 months) since time of acute infection. A high proportion of PASC patients reported that they have a moderate or severe limitation in their ability to carry out their usual activities, 38% report their ability to work is severely limited and 33% report a moderate, or higher, level of anxiety or depression. Conclusion: The results of this survey of an Irish cohort with PASC are in line with reports from other settings, and we confirm that patients with PASC reported prolonged, multi-system symptoms which can significantly impact quality of life, affect ability to work and cause significant disability. Dedicated multidisciplinary, cross specialty supports are required to improve outcomes of this patient group.

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