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1.
BMC Plant Biol ; 22(1): 220, 2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35484480

RESUMO

BACKGROUND: Tef (Eragrostis tef) is a tropical cereal domesticated and grown in the Ethiopian highlands, where it has been a staple food of Ethiopians for many centuries. Food insecurity and nutrient deficiencies are major problems in the country, so breeding for enhanced nutritional traits, such as Zn content, could help to alleviate problems with malnutrition. RESULTS: To understand the breeding potential of nutritional traits in tef a core set of 24 varieties were sequenced and their mineral content, levels of phytate and protein, as well as a number of nutritionally valuable phenolic compounds measured in grain. Significant variation in all these traits was found between varieties. Genome wide sequencing of the 24 tef varieties revealed 3,193,582 unique SNPs and 897,272 unique INDELs relative to the tef reference var. Dabbi. Sequence analysis of two key transporter families involved in the uptake and transport of Zn by the plant led to the identification of 32 Zinc Iron Permease (ZIP) transporters and 14 Heavy Metal Associated (HMA) transporters in tef. Further analysis identified numerous variants, of which 14.6% of EtZIP and 12.4% of EtHMA variants were non-synonymous changes. Analysis of a key enzyme in flavanol synthesis, flavonoid 3'-hydroxylase (F3'H), identified a T-G variant in the tef homologue Et_s3159-0.29-1.mrna1 that was associated with the differences observed in kaempferol glycoside and quercetin glycoside levels. CONCLUSION: Wide genetic and phenotypic variation was found in 24 Ethiopian tef varieties which would allow for breeding gains in many nutritional traits of importance to human health.


Assuntos
Eragrostis , Mapeamento Cromossômico , Grão Comestível/genética , Eragrostis/genética , Etiópia , Variação Genética , Humanos , Melhoramento Vegetal
2.
Reprod Biomed Online ; 44(2): 316-323, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34893436

RESUMO

RESEARCH QUESTION: Does endometrial scratching improve the chance of a live birth in women with polycystic ovary syndrome (PCOS) undergoing ovulation induction and trying to conceive? DESIGN: An international, multicentre, randomized, sham-controlled trial across six fertility clinics in three countries (New Zealand, UK and Brazil). Women with a diagnosis of PCOS who were planning to commence ovulation induction cycles (at least three cycles) in order to conceive were randomly assigned to receive the pipelle (scratch) procedure or a sham (placebo) procedure in the first cycle of ovulation induction. Women kept a diary of ovulation induction and sexual intercourse timing over three consecutive cycles and pregnancies were followed up to live birth. Primary outcome was live birth and secondary outcomes were clinical pregnancy, ongoing pregnancy, multiple pregnancy, adverse pregnancy outcomes, neonatal outcomes, bleeding following procedure and pain score following procedure. RESULTS: A total of 117 women were randomized; 58 to the scratch group and 59 to the sham group. Live birth occurred in 11 (19%) women in the scratch group and 14 (24%) in the sham group (odds ratio 0.76, 95% confidence interval [CI] 0.30-1.92). Secondary outcomes were similar in each group. Significantly higher pain scores were reported in the scratch group (adjusted mean difference 3.2, 95% CI 2.5-3.9) when measured on a visual analogue scale. CONCLUSION: No difference was detected in live birth rate for women with PCOS who received an endometrial scratch when trying to conceive using ovulation induction; however, uncertainty remains due to the small sample size in this study.


Assuntos
Infertilidade Feminina , Síndrome do Ovário Policístico , Feminino , Fertilização in vitro/métodos , Humanos , Recém-Nascido , Infertilidade Feminina/complicações , Infertilidade Feminina/terapia , Nascido Vivo , Masculino , Indução da Ovulação/métodos , Dor , Síndrome do Ovário Policístico/complicações , Gravidez , Taxa de Gravidez
3.
BMC Plant Biol ; 21(1): 524, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34758742

RESUMO

BACKGROUND: Grain size is thought to be a major component of yield in many plant species. Here we set out to understand if knowledge from other cereals such as rice could translate to increased yield gains in wheat and lead to increased nitrogen use efficiency. Previous findings that the overexpression of OsBG1 in rice increased yields while increasing seed size suggest translating gains from rice to other cereals may help to increase yields. RESULTS: The orthologous genes of OsBG1 were identified in wheat. One homoeologous wheat gene was cloned and overexpressed in wheat to understand its role in controlling seed size. Potential alteration in the nutritional profile of the grains were also analyzed in wheat overexpressing TaBG1. It was found that increased TaBG1-A expression could indeed lead to larger seed size but was linked to a reduction in seed number per plant leading to no significant overall increase in yield. Other important components of yield such as biomass or tillering did not change significantly with increased TaBG1-A expression. The nutritional profile of the grain was altered, with a significant decrease in the Zn levels in the grain associated with increased seed size, but Fe and Mn concentrations were unchanged. Protein content of the wheat grain also fell under moderate N fertilization levels but not under deficient or adequate levels of N. CONCLUSIONS: TaBG1 does control seed size in wheat but increasing the seed size per se does not increase yield and may come at the cost of lower concentrations of essential elements as well as potentially lower protein content. Nevertheless, TaBG1 could be a useful target for further breeding efforts in combination with other genes for increased biomass.


Assuntos
Genes de Plantas , Sementes/genética , Triticum/genética , Biomassa , Grão Comestível/química , Grão Comestível/genética , Grão Comestível/metabolismo , Nitrogênio/metabolismo , Valor Nutritivo/genética , Plantas Geneticamente Modificadas , Sementes/anatomia & histologia , Sementes/química , Sementes/metabolismo , Triticum/anatomia & histologia , Triticum/química , Triticum/metabolismo
4.
BMC Plant Biol ; 21(1): 212, 2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-33975563

RESUMO

BACKGROUND: Anemia is thought to affect up to 1.6 billion people worldwide. One of the major contributors to low iron (Fe) absorption is a higher proportion of cereals compared to meats and pulse crops in people's diets. This has now become a problem in both the developed and developing world, as a result of both modern food choice and food availability. Bread wheat accounts for 20 % of the calories consumed by humans and is an important source of protein, vitamins and minerals meaning it could be a major vehicle for bringing more bioavailable Fe into the diet. RESULTS: To investigate whether breeding for higher concentrations of Fe in wheat grains could help increase Fe absorption, a multiparent advanced generation intercross (MAGIC) population, encompassing more than 80 % of UK wheat polymorphism, was grown over two seasons in the UK. The population was phenotyped for both Fe concentration and Fe bioavailability using an established Caco-2 cell bioassay. It was found that increasing Fe concentrations in the grains was not correlated with higher Fe bioavailability and that the underlying genetic regions controlling grain Fe concentrations do not co-localise with increased Fe absorption. Furthermore, we show that phytate concentrations do not correlate with Fe bioavailability in our wheat population and thus phytate-binding is insufficient to explain the lack of correlation between Fe bioavailability and Fe concentrations in the wheat grain. Finally, we observed no (Fe bioavailability) or low (Fe concentration) correlation between years for these traits, confirming that both are under strong environmental influence. CONCLUSIONS: This suggests that breeders will have to select not only for Fe concentrations directly in grains, but also increased bioavailability. However the use of numerous controls and replicated trials limits the practicality of adoption of screening by Caco-2 cells by many breeders.


Assuntos
Disponibilidade Biológica , Grão Comestível/química , Ferro da Dieta/análise , Ferro da Dieta/metabolismo , Triticum/química , Triticum/genética , Triticum/metabolismo , Produtos Agrícolas/química , Produtos Agrícolas/genética , Produtos Agrícolas/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Variação Genética , Genótipo , Melhoramento Vegetal , Reino Unido
5.
New Phytol ; 230(2): 629-640, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33124693

RESUMO

Wheat is the most widely grown crop globally, providing 20% of all human calories and protein. Achieving step changes in genetic yield potential is crucial to ensure food security, but efforts are thwarted by an apparent trade-off between grain size and number. Expansins are proteins that play important roles in plant growth by enhancing stress relaxation in the cell wall, which constrains cell expansion. Here, we describe how targeted overexpression of an α-expansin in early developing wheat seeds leads to a significant increase in grain size without a negative effect on grain number, resulting in a yield boost under field conditions. The best-performing transgenic line yielded 12.3% higher average grain weight than the control, and this translated to an increase in grain yield of 11.3% in field experiments using an agronomically appropriate plant density. This targeted transgenic approach provides an opportunity to overcome a common bottleneck to yield improvement across many crops.


Assuntos
Expressão Ectópica do Gene , Triticum , Produtos Agrícolas/metabolismo , Grão Comestível/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sementes/genética , Sementes/metabolismo , Triticum/genética , Triticum/metabolismo
6.
Theor Appl Genet ; 134(6): 1645-1662, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33900415

RESUMO

In the coming decades, larger genetic gains in yield will be necessary to meet projected demand, and this must be achieved despite the destabilizing impacts of climate change on crop production. The root systems of crops capture the water and nutrients needed to support crop growth, and improved root systems tailored to the challenges of specific agricultural environments could improve climate resiliency. Each component of root initiation, growth and development is controlled genetically and responds to the environment, which translates to a complex quantitative system to navigate for the breeder, but also a world of opportunity given the right tools. In this review, we argue that it is important to know more about the 'hidden half' of crop plants and hypothesize that crop improvement could be further enhanced using approaches that directly target selection for root system architecture. To explore these issues, we focus predominantly on bread wheat (Triticum aestivum L.), a staple crop that plays a major role in underpinning global food security. We review the tools available for root phenotyping under controlled and field conditions and the use of these platforms alongside modern genetics and genomics resources to dissect the genetic architecture controlling the wheat root system. To contextualize these advances for applied wheat breeding, we explore questions surrounding which root system architectures should be selected for, which agricultural environments and genetic trait configurations of breeding populations are these best suited to, and how might direct selection for these root ideotypes be implemented in practice.


Assuntos
Mudança Climática , Melhoramento Vegetal , Raízes de Plantas/fisiologia , Triticum/genética , Produtos Agrícolas/genética , Genes de Plantas , Fenótipo , Raízes de Plantas/genética , Triticum/fisiologia
7.
BMC Plant Biol ; 18(1): 115, 2018 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-29884124

RESUMO

BACKGROUND: Phosphorus (P) is an essential macronutrient for plant growth, and is required in large quantities by elite varieties of crops to maintain yields. Approximately 70% of global cultivated land suffers from P deficiency, and it has recently been estimated that worldwide P resources will be exhausted by the end of this century, increasing the demand for crops more efficient in their P usage. A greater understanding of how plants are able to maintain yield with lower P inputs is, therefore, highly desirable to both breeders and farmers. Here, we clone the wheat (Triticum aestivum L.) homologue of the rice PSTOL gene (OsPSTOL), and characterize its role in phosphate nutrition plus other agronomically important traits. RESULTS: TaPSTOL is a single copy gene located on the short arm of chromosome 5A, encoding a putative kinase protein, and shares a high level of sequence similarity to OsPSTOL. We re-sequenced TaPSTOL from 24 different wheat accessions and (3) three T. durum varieties. No sequence differences were detected in 26 of the accessions, whereas two indels were identified in the promoter region of one of the durum wheats. We characterised the expression of TaPSTOL under different P concentrations and demonstrated that the promoter was induced in root tips and hairs under P limiting conditions. Overexpression and RNAi silencing of TaPSTOL in transgenic wheat lines showed that there was a significant effect upon root biomass, flowering time independent of P treatment, tiller number and seed yield, correlating with the expression of TaPSTOL. However this did not increase PUE as elevated P concentration in the grain did not correspond to increased yields. CONCLUSIONS: Manipulation of TaPSTOL expression in wheat shows it is responsible for many of the previously described phenotypic advantages as OsPSTOL except yield. Furthermore, we show TaPSTOL contributes to additional agronomically important traits including flowering time and grain size. Analysis of TaPSTOL sequences from a broad selection of wheat varieties, encompassing 91% of the genetic diversity in UK bread wheat, showed that there is very little genetic variation in this gene, which would suggest that this locus may have been under high selection pressure.


Assuntos
Genes de Plantas/genética , Triticum/genética , Grão Comestível/crescimento & desenvolvimento , Grão Comestível/metabolismo , Flores/crescimento & desenvolvimento , Flores/metabolismo , Genes de Plantas/fisiologia , Fosfatos/metabolismo , Característica Quantitativa Herdável , Análise de Sequência de DNA , Triticum/crescimento & desenvolvimento
10.
Inorg Chem ; 56(3): 1375-1385, 2017 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-28103034

RESUMO

The impact of the metal size and Lewis acidity on the polymerization activity of group 13 metal complexes was studied, and it was shown that, within the same ligand family, indium complexes are far more reactive and selective than their gallium analogues. To this end, gallium and aluminum complexes supported by a tridentate diaminophenolate ligand, as well as gallium complexes supported by N,N'-ethylenebis(salicylimine)(salen) ligands, were synthesized and compared to their indium analogues. Using the tridentate ligand set, it was possible to isolate the gallium chloride complexes 3 and (±)-4 and the aluminum analogues 5 and (±)-6. The alkoxygallium complex (±)-2, supported by a salen ligand, was also prepared and characterized and, along with the three-component system GaCl3/BnOH/NEt3, was tested for the ring-opening polymerization of lactide and ε-caprolactone. The polymerization rates and selectivities of both systems were significantly lower than those for the indium analogues. The reaction of (±)-2 with 1 equiv of lactide forms the first insertion product, which is stable in solution and can be characterized at room temperature. In order to understand the differences of the reactivity within the group 13 metal complexes, a Lewis acidity study using triethylphosphine oxide (the Gutmann-Beckett method) was undertaken for a series of aluminum, gallium, and indium halide complexes; this study shows that indium halide complexes are less Lewis acidic than their aluminum and gallium analogues. Density functional theory calculations show that the Mulliken charges for the indium complexes are higher than those for the gallium analogues. These data suggest that the impact of ligands on the reactivity is more significant than that of the metal Lewis acidity.

11.
Plant Physiol ; 169(1): 512-29, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26157115

RESUMO

Heterotrimeric G proteins, consisting of Gα, Gß, and Gγ subunits, are a conserved signal transduction mechanism in eukaryotes. However, G protein subunit numbers in diploid plant genomes are greatly reduced as compared with animals and do not correlate with the diversity of functions and phenotypes in which heterotrimeric G proteins have been implicated. In addition to GPA1, the sole canonical Arabidopsis (Arabidopsis thaliana) Gα subunit, Arabidopsis has three related proteins: the extra-large GTP-binding proteins XLG1, XLG2, and XLG3. We demonstrate that the XLGs can bind Gßγ dimers (AGB1 plus a Gγ subunit: AGG1, AGG2, or AGG3) with differing specificity in yeast (Saccharomyces cerevisiae) three-hybrid assays. Our in silico structural analysis shows that XLG3 aligns closely to the crystal structure of GPA1, and XLG3 also competes with GPA1 for Gßγ binding in yeast. We observed interaction of the XLGs with all three Gßγ dimers at the plasma membrane in planta by bimolecular fluorescence complementation. Bioinformatic and localization studies identified and confirmed nuclear localization signals in XLG2 and XLG3 and a nuclear export signal in XLG3, which may facilitate intracellular shuttling. We found that tunicamycin, salt, and glucose hypersensitivity and increased stomatal density are agb1-specific phenotypes that are not observed in gpa1 mutants but are recapitulated in xlg mutants. Thus, XLG-Gßγ heterotrimers provide additional signaling modalities for tuning plant G protein responses and increase the repertoire of G protein heterotrimer combinations from three to 12. The potential for signal partitioning and competition between the XLGs and GPA1 is a new paradigm for plant-specific cell signaling.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Proteínas Heterotriméricas de Ligação ao GTP/metabolismo , Subunidades Proteicas/metabolismo , Transdução de Sinais , Sequência de Aminoácidos , Arabidopsis/efeitos dos fármacos , Proteínas de Arabidopsis/química , Membrana Celular/metabolismo , Simulação por Computador , Proteínas Heterotriméricas de Ligação ao GTP/química , Dados de Sequência Molecular , Mutação/genética , Sinais de Localização Nuclear/química , Fenótipo , Ligação Proteica/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Frações Subcelulares/metabolismo , Nicotiana/metabolismo , Tunicamicina/farmacologia , Técnicas do Sistema de Duplo-Híbrido
12.
Plant J ; 78(3): 398-410, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24547775

RESUMO

The Zn/Cd hyperaccumulator, Noccaea caerulescens, has been studied extensively for its ability to accumulate high levels of Zn and Cd in its leaves. Previous studies have indicated that the Zn and Cd hyperaccumulation trait exhibited by this species involves different transport and tolerance mechanisms. It has also been well documented that certain ecotypes of N. caerulescens are much better Cd hyperaccumulators than others. However, there does not seem to be much ecotypic variation for Zn hyperaccumulation in N. caerulescens. In this study we employed a comparative transcriptomics approach to look at root and shoot gene expression in Ganges and Prayon plants in response to Cd stress to identify transporter genes that were more highly expressed in either the roots or shoots of the superior Cd accumulator, Ganges. Comparison of the transcriptomes from the two ecotypes of Noccaea caerulescens identified a number of genes that encoded metal transporters that were more highly expressed in the Ganges ecotype in response to Cd stress. Characterization of one of these transporters, NcNramp1, showed that it is involved in the influx of Cd across the endodermal plasma membrane and thus may play a key role in Cd flux into the stele and root-to-shoot Cd transport. NcNramp1 may be one of the main transporters involved in Cd hyperaccumulation in N. caerulescens and copy number variation appears to be the main reason for high NcNramp1 gene expression underlying the increased Cd accumulation in the Ganges ecotype.


Assuntos
Brassicaceae/genética , Brassicaceae/metabolismo , Cádmio/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Brotos de Planta/genética , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Arabidopsis/metabolismo , Cádmio/farmacocinética , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Variações do Número de Cópias de DNA , Ecótipo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ferro/metabolismo , Ferro/farmacologia , Proteínas de Plantas/genética , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Plantas Geneticamente Modificadas , Zinco/metabolismo
13.
J Integr Plant Biol ; 56(3): 271-80, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24433538

RESUMO

To gain a better understanding of the regulation of Zn homeostasis in plants and the degree of conservation of Zn homeostasis between plants and yeast, a cDNA library from the Zn/Cd hyperaccumulating plant species, Noccaea caerulescens, was screened for its ability to restore growth under Zn limiting conditions in the yeast mutant zap1Δ. ZAP1 is a transcription factor that activates the Zn dependent transcription of yeast genes involved in Zn uptake, including ZRT1, the yeast high affinity Zn transporter. From this screen two members of the E2F family of transcription factors were found to activate ZRT1 expression in a Zn independent manner. The activation of ZRT1 by the plant E2F proteins involves E2F-mediated activation of a yeast GATA transcription factor which in turn activates ZRT1 expression. A ZRT1 promoter region necessary for activation by E2F and GATA proteins is upstream of two zinc responsive elements previously shown to bind ZAP1 in ZRT1. This activation may not involve direct binding of E2F to the ZRT1 promoter. The expression of E2F genes in yeast does not replace function of ZAP1; instead it appears to activate a novel GATA regulatory pathway involved in Zn uptake and homeostasis that is not Zn responsive.


Assuntos
Brassicaceae/metabolismo , Fatores de Transcrição GATA/metabolismo , Homeostase , Saccharomyces cerevisiae/metabolismo , Transdução de Sinais , Zinco/metabolismo , Transporte Biológico/efeitos dos fármacos , Transporte Biológico/genética , Brassicaceae/efeitos dos fármacos , Fatores de Transcrição E2F/metabolismo , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Teste de Complementação Genética , Homeostase/efeitos dos fármacos , Homeostase/genética , Ferro/farmacologia , Mutação/genética , Fenótipo , Regiões Promotoras Genéticas/genética , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Deleção de Sequência/genética , Transcrição Gênica/efeitos dos fármacos
14.
J Exp Bot ; 64(1): 369-81, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23264639

RESUMO

A better understanding of the role of the Arabidopsis ZIP family of micronutrient transporters is necessary in order to advance our understanding of plant Zn, Fe, Mn, and Cu homeostasis. In the current study, the 11 Arabidopsis ZIP family members not yet well characterized were first screened for their ability to complement four yeast mutants defective in Zn, Fe, Mn, or Cu uptake. Six of the Arabidopsis ZIP genes complemented a yeast Zn uptake-deficient mutant, one was able partially to complement a yeast Fe uptake-deficient mutant, six ZIP family members complemented an Mn uptake-deficient mutant, and none complemented the Cu uptake-deficient mutant. AtZIP1 and AtZIP2 were then chosen for further study, as the preliminary yeast and in planta analysis suggested they both may be root Zn and Mn transporters. In yeast, AtZIP1 and AtZIP2 both complemented the Zn and Mn uptake mutants, suggesting that they both may transport Zn and/or Mn. Expression of both genes is localized to the root stele, and AtZIP1 expression was also found in the leaf vasculature. It was also found that AtZIP1 is a vacuolar transporter, while AtZIP2 is localized to the plasma membrane. Functional studies with Arabidopsis AtZIP1 and AtZIP2 T-DNA knockout lines suggest that both transporters play a role in Mn (and possibly Zn) translocation from the root to the shoot. AtZIP1 may play a role in remobilizing Mn from the vacuole to the cytoplasm in root stellar cells, and may contribute to radial movement to the xylem parenchyma. AtZIP2, on the other hand, may mediate Mn (and possibly Zn) uptake into root stellar cells, and thus also may contribute to Mn/Zn movement in the stele to the xylem parenchyma, for subsequent xylem loading and transport to the shoot.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Homeostase , Manganês/metabolismo , Zinco/metabolismo , Adaptação Fisiológica/efeitos dos fármacos , Adaptação Fisiológica/genética , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/isolamento & purificação , DNA Bacteriano/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Técnicas de Inativação de Genes , Teste de Complementação Genética , Homeostase/efeitos dos fármacos , Homeostase/genética , Manganês/toxicidade , Mutagênese Insercional/efeitos dos fármacos , Mutagênese Insercional/genética , Mutação/genética , Especificidade de Órgãos/efeitos dos fármacos , Especificidade de Órgãos/genética , Fenótipo , Plantas Geneticamente Modificadas , Transporte Proteico/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Saccharomyces cerevisiae/metabolismo , Frações Subcelulares/efeitos dos fármacos , Frações Subcelulares/metabolismo , Zinco/toxicidade
15.
Front Plant Sci ; 14: 1098175, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36818870

RESUMO

There is a large demand to reduce inputs for current crop production, particularly phosphate and nitrogen inputs which are the two most frequently added supplements to agricultural production. Gene characterization is often limited to the native species from which it was identified, but may offer benefits to other species. To understand if the rice gene Phosphate Starvation Tolerance 1 (PSTOL) OsPSTOL, a gene identified from rice which improves tolerance to low P growth conditions, might improve performance and provide the same benefit in wheat, OsPSTOL was transformed into wheat and expressed from a constitutive promoter. The ability of OsPSTOL to improve nutrient acquisition under low phosphate or low nitrogen was evaluated. Here we show that OsPSTOL works through a conserved pathway in wheat and rice to improve yields under both low phosphate and low nitrogen. This increase is yield is mainly driven by improved uptake from the soil driving increased biomass and ultimately increased seed number, but does not change the concentration of N in the straw or grain. Overexpression of OsPSTOL in wheat modifies N regulated genes to aid in this uptake whereas the putative homolog TaPSTOL does not suggesting that expression of OsPSTOL in wheat can help to improve yields under low input agriculture.

16.
Plant J ; 66(5): 852-62, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21457363

RESUMO

Cadmium (Cd) is a highly toxic heavy metal for plants, but several unique Cd-hyperaccumulating plant species are able to accumulate this metal to extraordinary concentrations in the aboveground tissues without showing any toxic symptoms. However, the molecular mechanisms underlying this hypertolerance to Cd are poorly understood. Here we have isolated and functionally characterized an allelic gene, TcHMA3 (heavy metal ATPase 3) from two ecotypes (Ganges and Prayon) of Thlaspi caerulescens contrasting in Cd accumulation and tolerance. The TcHMA3 alleles from the higher (Ganges) and lower Cd-accumulating ecotype (Prayon) share 97.8% identity, and encode a P(1B)-type ATPase. There were no differences in the expression pattern, cell-specificity of protein localization and transport substrate-specificity of TcHMA3 between the two ecotypes. Both alleles were characterized by constitutive expression in the shoot and root, a tonoplast localization of the protein in all leaf cells and specific transport activity for Cd. The only difference between the two ecotypes was the expression level of TcHMA3: Ganges showed a sevenfold higher expression than Prayon, partly caused by a higher copy number. Furthermore, the expression level and localization of TcHMA3 were different from AtHMA3 expression in Arabidopsis. Overexpression of TcHMA3 in Arabidopsis significantly enhanced tolerance to Cd and slightly increased tolerance to Zn, but did not change Co or Pb tolerance. These results indicate that TcHMA3 is a tonoplast-localized transporter highly specific for Cd, which is responsible for sequestration of Cd into the leaf vacuoles, and that a higher expression of this gene is required for Cd hypertolerance in the Cd-hyperaccumulating ecotype of T. caerulescens.


Assuntos
Adenosina Trifosfatases/metabolismo , Cádmio/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Thlaspi/genética , Adenosina Trifosfatases/genética , Alelos , Arabidopsis/genética , Clonagem Molecular , Dosagem de Genes , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Proteínas de Membrana Transportadoras/metabolismo , Filogenia , Proteínas de Plantas/genética , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Thlaspi/enzimologia , Thlaspi/crescimento & desenvolvimento , Transfecção , Leveduras/genética
17.
New Phytol ; 195(1): 113-23, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22524643

RESUMO

• In this paper, we conducted a detailed analysis of the ZIP family transporter, NcZNT1, in the zinc (Zn)/cadmium (Cd) hyperaccumulating plant species, Noccaea caerulescens, formerly known as Thlaspi caerulescens. NcZNT1 was previously suggested to be the primary root Zn/Cd uptake transporter. Both a characterization of NcZNT1 transport function in planta and in heterologous systems, and an analysis of NcZNT1 gene expression and NcZNT1 protein localization were carried out. • We show that NcZNT1 is not only expressed in the root epidermis, but also is highly expressed in the root and shoot vasculature, suggesting a role in long-distance metal transport. Also, NcZNT1 was found to be a plasma membrane transporter that mediates Zn but not Cd, iron (Fe), manganese (Mn) or copper (Cu) uptake into plant cells. • Two novel regions of the NcZNT1 promoter were identified which may be involved in both the hyperexpression of NcZNT1 and its ability to be regulated by plant Zn status. • In conclusion, we demonstrate here that NcZNT1 plays a role in Zn and not Cd uptake from the soil, and based on its strong expression in the root and shoot vasculature, could be involved in long-distance transport of Zn from the root to the shoot via the xylem.


Assuntos
Brassicaceae/metabolismo , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Zinco/metabolismo , Arabidopsis/genética , Brassicaceae/citologia , Brassicaceae/genética , Cádmio/metabolismo , Cádmio/farmacocinética , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Cobre/metabolismo , Cobre/farmacocinética , Regulação da Expressão Gênica de Plantas , Manganês/metabolismo , Manganês/farmacocinética , Células Vegetais , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas , Deleção de Sequência , Zinco/farmacocinética
18.
Commun Biol ; 5(1): 193, 2022 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-35241776

RESUMO

There is a strong pressure to reduce nitrogen (N) fertilizer inputs while maintaining or increasing current cereal crop yields. We show that overexpression of TaDWF4-B, the dominant shoot expressed homoeologue of OsDWF4, in wheat can increase plant productivity by up to 105% under a range of N levels on marginal soils, resulting in increased N use efficiency (NUE). We show that a two to four-fold increase in TaDWF4 transcript levels enhances the responsiveness of genes regulated by N. The productivity increases seen were primarily due to the maintenance of photosystem II operating efficiency and carbon assimilation in plants when grown under limiting N conditions and not an overall increase in photosynthesis capacity. The increased biomass production and yield per plant in TaDWF4 OE lines could be linked to modified carbon partitioning and changes in expression pattern of the growth regulator Target Of Rapamycin, offering a route towards breeding for sustained yield and lower N inputs.


Assuntos
Nitrogênio , Triticum , Carbono/metabolismo , Fertilizantes , Nitrogênio/metabolismo , Melhoramento Vegetal
19.
Fertil Steril ; 117(3): 612-619, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35105443

RESUMO

OBJECTIVE: To investigate whether endometrial scratching increases the chance of live birth in women with unexplained infertility attempting to conceive without assisted reproductive technology. DESIGN: Randomized, placebo-controlled, participant-blind, multicenter international trial. SETTING: Fertility clinics. PATIENT(S): Women with a diagnosis of unexplained infertility trying to conceive without assistance. INTERVENTION(S): Participants were randomly assigned to receive an endometrial biopsy or a placebo procedure (placement of a biopsy catheter in the posterior fornix, without inserting it into the external cervical os). Both groups performed regular unprotected intercourse with the intention of conceiving over three consecutive study cycles. MAIN OUTCOME MEASURE(S): The primary outcome was live birth. RESULT(S): A total of 220 women underwent randomization. The live birth rate was 9% (10 of 113 women) in the endometrial-scratch group and 7% (7 of 107 women) in the control group (adjusted OR, 1.39; 95% CI, 0.50-4.03). There were no differences between the groups in the secondary outcomes of clinical pregnancy, viable pregnancy, ongoing pregnancy, and miscarriage. Endometrial scratching was associated with a higher pain score on a 10-point scale (adjusted mean difference, 3.07; 95% CI, 2.53-3.60). CONCLUSION(S): This trial did not find evidence that endometrial scratching improves the live birth rate in women with unexplained infertility trying to conceive without assistance. CLINICAL TRIAL REGISTRATION NUMBER: Australian New Zealand Clinical Trials Registry ACTRN12614000656639.


Assuntos
Cateterismo/métodos , Endométrio/fisiologia , Fertilização/fisiologia , Infertilidade Feminina/epidemiologia , Infertilidade Feminina/terapia , Nascido Vivo/epidemiologia , Biópsia , Cateterismo/instrumentação , Endométrio/patologia , Feminino , Humanos , Infertilidade Feminina/diagnóstico , Internacionalidade , Gravidez , Método Simples-Cego , Resultado do Tratamento
20.
Front Plant Sci ; 11: 583374, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33324433

RESUMO

The application of CRISPR/Cas9 technologies has transformed our ability to target and edit designated regions of a genome. It's broad adaptability to any organism has led to countless advancements in our understanding of many biological processes. Many current tools are designed for simple plant systems such as diploid species, however, efficient deployment in crop species requires a greater efficiency of editing as these often contain polyploid genomes. Here, we examined the role of temperature to understand if CRISPR/Cas9 editing efficiency can be improved in wheat. The recent finding that plant growth under higher temperatures could increase mutation rates was tested with Cas9 expressed from two different promoters in wheat. Increasing the temperature of the tissue culture or of the seed germination and early growth phase increases the frequency of mutation in wheat when the Cas9 enzyme is driven by the ZmUbi promoter but not OsActin. In contrast, Cas9 expression driven by the OsActin promoter did not increase the mutations detected in either transformed lines or during the transformation process itself. These results demonstrate that CRISPR/Cas9 editing efficiency can be significantly increased in a polyploid cereal species with a simple change in growth conditions to facilitate increased mutations for the creation of homozygous or null knock-outs.

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