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1.
Nature ; 546(7656): 148-152, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28538728

RESUMO

The domesticated sunflower, Helianthus annuus L., is a global oil crop that has promise for climate change adaptation, because it can maintain stable yields across a wide variety of environmental conditions, including drought. Even greater resilience is achievable through the mining of resistance alleles from compatible wild sunflower relatives, including numerous extremophile species. Here we report a high-quality reference for the sunflower genome (3.6 gigabases), together with extensive transcriptomic data from vegetative and floral organs. The genome mostly consists of highly similar, related sequences and required single-molecule real-time sequencing technologies for successful assembly. Genome analyses enabled the reconstruction of the evolutionary history of the Asterids, further establishing the existence of a whole-genome triplication at the base of the Asterids II clade and a sunflower-specific whole-genome duplication around 29 million years ago. An integrative approach combining quantitative genetics, expression and diversity data permitted development of comprehensive gene networks for two major breeding traits, flowering time and oil metabolism, and revealed new candidate genes in these networks. We found that the genomic architecture of flowering time has been shaped by the most recent whole-genome duplication, which suggests that ancient paralogues can remain in the same regulatory networks for dozens of millions of years. This genome represents a cornerstone for future research programs aiming to exploit genetic diversity to improve biotic and abiotic stress resistance and oil production, while also considering agricultural constraints and human nutritional needs.


Assuntos
Evolução Molecular , Flores/genética , Flores/fisiologia , Genoma de Planta/genética , Helianthus/genética , Helianthus/metabolismo , Óleos de Plantas/metabolismo , Aclimatação/genética , Duplicação Gênica/genética , Regulação da Expressão Gênica de Plantas , Variação Genética , Genômica , Helianthus/classificação , Análise de Sequência de DNA , Estresse Fisiológico/genética , Óleo de Girassol , Transcriptoma/genética
2.
J Exp Bot ; 65(14): 3927-47, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24567494

RESUMO

A total of 16 BnaGLN1 genes coding for cytosolic glutamine synthetase isoforms (EC 6.3.1.2.) were found in the Brassica napus genome. The total number of BnaGLN1 genes, their phylogenetic relationships, and genetic locations are in agreement with the evolutionary history of Brassica species. Two BnaGLN1.1, two BnaGLN1.2, six BnaGLN1.3, four BnaGLN1.4, and two BnaGLN1.5 genes were found and named according to the standardized nomenclature for the Brassica genus. Gene expression showed conserved responses to nitrogen availability and leaf senescence among the Brassiceae tribe. The BnaGLN1.1 and BnaGLN1.4 families are overexpressed during leaf senescence and in response to nitrogen limitation. The BnaGLN1.2 family is up-regulated under high nitrogen regimes. The members of the BnaGLN1.3 family are not affected by nitrogen availability and are more expressed in stems than in leaves. Expression of the two BnaGLN1.5 genes is almost undetectable in vegetative tissues. Regulations arising from plant interactions with their environment (such as nitrogen resources), final architecture, and therefore sink-source relations in planta, seem to be globally conserved between Arabidopsis and B. napus. Similarities of the coding sequence (CDS) and protein sequences, expression profiles, response to nitrogen availability, and ageing suggest that the roles of the different GLN1 families have been conserved among the Brassiceae tribe. These findings are encouraging the transfer of knowledge from the Arabidopsis model plant to the B. napus crop plant. They are of special interest when considering the role of glutamine synthetase in crop yield and grain quality in maize and wheat.


Assuntos
Brassica napus/enzimologia , Brassica napus/genética , Citosol/enzimologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Nitrogênio/farmacologia , Folhas de Planta/crescimento & desenvolvimento , Sequência de Aminoácidos , Brassica napus/efeitos dos fármacos , Brassica rapa/enzimologia , Brassica rapa/genética , Mapeamento Cromossômico , Sequência Conservada , Bases de Dados de Ácidos Nucleicos , Etiquetas de Sequências Expressas , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Loci Gênicos , Glutamato-Amônia Ligase/química , Glutamato-Amônia Ligase/genética , Glutamato-Amônia Ligase/metabolismo , Anotação de Sequência Molecular , Dados de Sequência Molecular , Nitratos/farmacologia , Fases de Leitura Aberta/genética , Filogenia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reprodução/genética , Alinhamento de Sequência
3.
Theor Appl Genet ; 126(5): 1151-65, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23358861

RESUMO

Several QTLs for cell wall degradability and lignin content were previously detected in the F288 × F271 maize RIL progeny, including a set of major QTLs located in bin 6.06. Unexpectedly, allelic sequencing of genes located around the bin 6.06 QTL positions revealed a monomorphous region, suggesting that these QTLs were likely "ghost" QTLs. Refining the positions of all QTLs detected in this population was thus considered, based on a linkage map densification in most important QTL regions, and in several large still unmarked regions. Re-analysis of data with an improved genetic map (173 markers instead of 108) showed that ghost QTLs located in bin 6.06 were then fractionated over two QTL positions located upstream and downstream of the monomorphic region. The area located upstream of bin 6.06 position carried the major QTLs, which explained from 37 to 59 % of the phenotypic variation for per se values and extended on only 6 cM, corresponding to a physical distance of 2.2 Mbp. Among the 92 genes present in the corresponding area of the B73 maize reference genome, nine could putatively be considered as involved in the formation of the secondary cell wall [bHLH, FKBP, laccase, fasciclin, zinc finger C2H2-type and C3HC4-type (two genes), NF-YB, and WRKY]. In addition, based on the currently improved genetic map, eight QTLs were detected in bin 4.09, while only one QTL was highlighted in the initial investigation. Moreover, significant epistatic interaction effects were shown for all traits between these QTLs located in bin 4.09 and the major QTLs located in bin 6.05. Three genes related to secondary cell wall assembly (ZmMYB42, COV1-like, PAL-like) underlay QTL support intervals in this newly identified bin 4.09 region. The current investigations, even if they were based only on one RIL progeny, illustrated the interest of a targeted marker mapping on a genetic map to improve QTL position.


Assuntos
Parede Celular/genética , Mapeamento Cromossômico , Genes de Plantas/genética , Ligação Genética , Locos de Características Quantitativas , Zea mays/genética , Cromossomos de Plantas , Repetições de Microssatélites , Fenótipo
4.
Artigo em Inglês | MEDLINE | ID: mdl-35742601

RESUMO

The different waves of the COVID-19 pandemic caused dramatic issues regarding the organization of care. In this context innovative solutions have to be developed in a timely manner to adapt to the organization of the care. The establishment of middle care (MC) units is a bright example of such an adaptation. A multidisciplinary MC team, including expert and non-expert respiratory health care personnel, was developed and trained to work in a COVID-19 MC unit. Important educational resources were set up to ensure rapid and effective training of the MC team, limiting the admission or delaying transfers to ICU and ensuring optimal management of palliative care. We conducted a retrospective analysis of patient data in the MC unit during the second COVID-19 wave in Belgium. The aim of this study was to demonstrate the feasibility of quickly developing an effective respiratory MC unit mixing respiratory expert and non-expert members from outside ICUs. The establishment of an MC unit during a pandemic is feasible and needed. MC units possibly relieve the pressure exerted on ICUs. A highly trained multidisciplinary team is key to ensuring the success of an MC unit during such kind of a pandemic.


Assuntos
COVID-19 , COVID-19/epidemiologia , Humanos , Unidades de Terapia Intensiva , Pandemias , Estudos Retrospectivos , SARS-CoV-2
5.
JPEN J Parenter Enteral Nutr ; 45(6): 1153-1163, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33666263

RESUMO

BACKGROUND: Among hospitalized patients with coronavirus disease 2019 (COVID-19), up to 12% may require intensive care unit (ICU) management. The aim of this prospective cohort study is to assess nutrition status and outcome in patients with COVID-19 following ICU discharge. METHODS: Patients requiring a minimum of 14 days' stay in the ICU with mechanical ventilation were included. Nutrition status was assessed at inclusion (ICU discharge) and follow-up (after 15, 30, and 60 days). All patients had standardized medical nutrition therapy with defined targets regarding energy (30 kcal/kg/d) and protein intake (1.5 g/kg/d). RESULTS: Fifteen patients were included (67% males); the median age was 60 (33-75) years old. Body mass index at ICU admission was 25.7 (IQR, 24-31) kg/m². After a median ICU stay of 33 (IQR, 26-39) days, malnutrition was present in all patients (11.3% median weight loss and/or low muscle mass based on handgrip strength measurement). Because of postintubation dysphagia in 60% of patients, enteral nutrition was administered (57% nasogastric tube; 43% percutaneous endoscopic gastrostomy). After 2 months, a significant improvement in muscle strength was observed (median handgrip strength, 64.7% [IQR, 51%-73%] of the predicted values for age vs 19% [IQR, 4.8%-28.4%] at ICU discharge [P < 0.0005]), as well as weight gain of 4.3 kg (IQR, 2.7-6.7 kg) (P < 0.0002). CONCLUSIONS: Critically ill patients with COVID-19 requiring ICU admission and mechanical ventilation have malnutrition and low muscle mass at ICU discharge. Nutrition parameters improve during rehabilitation with standardized medical nutrition therapy.


Assuntos
COVID-19 , Estado Terminal , Adulto , Idoso , Cuidados Críticos , Nutrição Enteral , Feminino , Força da Mão , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , SARS-CoV-2
6.
New Phytol ; 180(4): 899-910, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19138233

RESUMO

The best characterized form of resistance is gene-for-gene resistance. Less well characterized is nonhost resistance in which an entire plant species is resistant to an entire pathogen species. Here, different rice genotypes were inoculated with host and nonhost strains of Magnaporthe isolated from rice, wheat and crabgrass. The different types of interactions were characterized at a cytological level using a 3,3'-diaminobenzidine (DAB) stain to investigate the occurrence of reactive oxygen intermediates or by observing the occurrence of cellular autofluorescence. Gene expression of a set of selected PR-genes was analysed using quantitative real-time polymerase chain reaction. Inoculation with the isolate from crabgrass resulted in a lack of penetration. The wheat isolate induced a hypersensitive response with varying degrees of pathogen growth inside the invaded cell according to the rice genotype. Expression analysis of our PR-gene set revealed clear differences between the different types of interactions in both kinetic and magnitude of gene induction. Our integrated study opens the way to the dissection of molecular components leading to nonhost reactions to Magnaporthe grisea in rice and points to novel sources of durable resistance to fungal plant pathogens in other cereal crops.


Assuntos
Interações Hospedeiro-Patógeno/genética , Magnaporthe/patogenicidade , Oryza/microbiologia , Doenças das Plantas/microbiologia , Digitaria/microbiologia , Fluorescência , Perfilação da Expressão Gênica , Interações Hospedeiro-Patógeno/fisiologia , Magnaporthe/classificação , Oryza/genética , Oryza/fisiologia , Doenças das Plantas/genética , Folhas de Planta/citologia , Triticum/microbiologia
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