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1.
Plant Direct ; 7(5): e495, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37228331

RESUMO

Manganese (Mn) is an essential micronutrient for plant growth but becomes toxic when present in excess. A number of Arabidopsis proteins are involved in Mn transport including ECA3, MTPs, and NRAMPs; however, their relative contributions to Mn homeostasis remain to be demonstrated. A major focus here was to clarify the importance of ECA3 in responding to Mn deficiency and toxicity using a range of mutants. We show that ECA3 localizes to the trans-Golgi and plays a major role in response to Mn deficiency with severe effects seen in eca3 nramp1 nramp2 under low Mn supply. ECA3 plays a minor role in Mn-toxicity tolerance, but only when the cis-Golgi-localized MTP11 is non-functional. We also use mutants and overexpressors to determine the relative contributions of MTP members to Mn homeostasis. The trans-Golgi-localized MTP10 plays a role in Mn-toxicity tolerance, but this is only revealed in mutants when MTP8 and MTP11 are non-functional and when overexpressed in mtp11 mutants. MTP8 and MTP10 confer greater Mn-toxicity resistance to the pmr1 yeast mutant than MTP11, and an important role for the first aspartate in the fifth transmembrane domain DxxxD motif is demonstrated. Overall, new insight into the relative influence of key transporters in Mn homeostasis is provided.

2.
Sci Rep ; 13(1): 7551, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-37160901

RESUMO

Plants require copper for normal growth and development and have evolved an efficient system for copper management based on transport proteins such as P1B-ATPases, also known as heavy metal ATPases (HMAs). Here, we report HMAs in eleven different Poaceae species, including wheat. Furthermore, the possible role of wheat HMAs in copper stress was investigated. BlastP searches identified 27 HMAs in wheat, and phylogenetic analysis based on the Maximum Likelihood method demonstrated a separation into four distinct clades. Conserved motif analysis, domain identification, gene structure, and transmembrane helices number were also identified for wheat HMAs using computational tools. Wheat seedlings grown hydroponically were subjected to elevated copper and demonstrated toxicity symptoms with effects on fresh weight and changes in expression of selected HMAs TaHMA7, TaHMA8, and TaHMA9 were upregulated in response to elevated copper, suggesting a role in wheat copper homeostasis. Further investigations on these heavy metal pumps can provide insight into strategies for enhancing crop heavy metal tolerance in the face of heavy metal pollution.


Assuntos
Cobre , Metais Pesados , Cobre/toxicidade , Triticum/genética , Poaceae , Filogenia , Metais Pesados/toxicidade , Adenosina Trifosfatases
3.
Front Public Health ; 10: 1067635, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36530724

RESUMO

Background: Preceded by a national media campaign, in May 2020, England switched to a soft opt-out system of organ donation which rests on the assumption that individuals meeting specific criteria have consented to organ donation unless they have expressed otherwise. We aimed to learn more about how the changes were communicated, how people responded and any discrepancies between key messages and how they were interpreted by the public. Methods: Summative content analysis of 286 stories and related reader-generated comments in leading UK online news sources (April 2019 to May 2021). Further detailed thematic analysis of 21 articles with reader-generated content, complemented by thematic content analysis coding of all 286 stories. Results: Most media coverage on both organ donation and the law change was positive, with little variation over time or between publications. The importance of organ donation, benefits of the law change, and emotive stories (often involving children) of those who had donated an organ described as "superheroes" or those who had received organs as benefiting from a "miracle" were frequently cited. In contrast, reader-generated comments were markedly more negative, for example, focusing on loss of individual freedom and lack of trust in the organ donation system. Commentators wished to be able to choose who their organs were donated to, were dismissive and blaming towards minority ethnic groups, including undermining legitimate worries about the compatibility of organ donation with religious beliefs and end of life cultural norms, understanding and acceptance of brain-stem death and systemic racism. Misinformation including use of inflammatory language was common. Conclusion: The portrayal of donors and recipients as extraordinary is unlikely to help to normalise organ donation. Undermining legitimate concerns, in particular those from ethnic minorities, can alienate and encourage harmful misinformation in underrepresented groups. The discrepancies between the tone of the articles and the readers comments suggests a lack of trust across the public, health, policy and media outlets. Easily accessible, ongoing and tailored sources are needed to mitigate misinformation and disinformation and ensure key messages are better understood and accepted in order to realise the ambitions of soft opt-out organ donation policies.


Assuntos
Obtenção de Tecidos e Órgãos , Criança , Humanos , Doadores de Tecidos , Confiança , Comunicação , Consentimento Livre e Esclarecido
4.
Br J Nurs ; 31(17): 876-877, 2022 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-36149429
5.
Ecol Food Nutr ; 61(5): 576-594, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35579381

RESUMO

The quality of food that children eat in early childhood has profound impacts on their future wellbeing. In England, many children eat the majority of meals in early years' settings including nurseries and childminders. We conducted 16 interviews with 18 stakeholders exploring food provision, the use of voluntary nutrition guidelines, and the effects of government support on the early years' sector. Key themes emerging from our thematic analysis included feeling insufficiently consulted, undervalued, support being unequally distributed, needing to fill multiple support roles for families, disagreement about the role and effect of voluntary nutrition standards, and being chronically underfunded.


Assuntos
Serviços de Alimentação , Política Nutricional , Criança , Pré-Escolar , Inglaterra , Humanos , Refeições , Estado Nutricional
6.
SSM Qual Res Health ; 2: 100142, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36606099

RESUMO

As childhood obesity and poor nutrition rates in England continue to rise, parents and childcare practitioners have key partnership roles in ensuring young children have healthy balanced diets. Yet little is known about parents' understanding and involvement in their childcare settings' food decisions and practices, and how this might be strengthened. Semi-structured interviews were carried out with a purposive sample of 59 parents with one or more children attending early years settings in England. Framework analysis was used to explore the interviews. Epstein's model of parental partnerships was adapted as a reflective lens for the findings, and their implication for early years' policy and practice. Parents reported a lack of two-way communication on food, and of opportunities for active, meaningful engagement around food and healthy eating outside of one-to-one discussions of their child's specific needs and requirements. Some parents reported a lack of trust in the food related information provided by their childcare setting. As young children spend more time in formal childcare, it is increasingly important that trusting collaborative relationships are built between parents and childcare practitioners to ensure that children have the best start in life. This study adds to the limited literature on parental involvement in early years settings. Findings suggest that more policy work and development is needed in the early years sector, particularly in ensuring clear and accessible guidelines on food in early years settings are readily available, and that practitioners and parents have more clarity about their mutual roles and responsibilities in this.

7.
BMC Public Health ; 21(1): 1631, 2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34488695

RESUMO

BACKGROUND: Hot weather leads to increased illness and deaths. The Heatwave Plan for England (HWP) aims to protect the population by raising awareness of the dangers of hot weather, especially for those most vulnerable. Individuals at increased risk to the effects of heat include older adults, particularly 75+, and those with specific chronic conditions, such as diabetes, respiratory and heart conditions. The HWP recommends specific protective actions which relate to five heat-health alert levels (levels 0-4). This study examines the attitudes to hot weather of adults in England, and the protective measures taken during a heatwave. METHODS: As part of a wider evaluation of the implementation and effects of the HWP, a survey (n = 3153) and focus groups, a form of group interview facilitated by a researcher, were carried out after the June 2017 level 3 heat-health alert. Survey respondents were categorised into three groups based on their age and health status: 'vulnerable' (aged 75+), 'potentially vulnerable' (aged 18-74 in poor health) and 'not vulnerable' (rest of the adult population) to hot weather. Multivariable logistic regression models identified factors associated with these groups taking protective measures. In-person group discussion, focused on heat-health, were carried out with 25 people, mostly aged 75 + . RESULTS: Most vulnerable and potentially vulnerable adults do not consider themselves at risk of hot weather and are unaware of the effectiveness of important protective behaviours. Only one-quarter of (potentially) vulnerable adults reported changing their behaviour as a result of hearing hot weather-related health advice during the level 3 alert period. Focus group findings showed many vulnerable adults were more concerned about the effects of the sun's ultra-violet radiation on the skin than on the effects of hot temperatures on health. CONCLUSIONS: Current public health messages appear to be insufficient, given the low level of (potentially) vulnerable adults changing their behaviour during hot weather. In the context of increasingly warmer summers in England due to climate change, public health messaging needs to convince (potentially) vulnerable adults of all the risks of hot weather (not just effects of sunlight on the skin) and of the importance of heat protective measures.


Assuntos
Mudança Climática , Temperatura Alta , Idoso , Atitude , Inglaterra/epidemiologia , Humanos , Estações do Ano , Tempo (Meteorologia)
8.
Hisp Health Care Int ; 19(2): 112-117, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33256476

RESUMO

INTRODUCTION: Hispanic women are affected by HIV. "Love, Sex & Choices" (LSC) is an innovative 12-episode urban soap opera video series targeting young adult Black women streamed to smartphones. This study purpose was to determine whether LSC is an acceptable HIV prevention intervention for female Hispanic college students in South Florida. METHOD: After institutional review board approval, female Hispanic college students were recruited from two campuses to watch the LSC video series and complete an online evaluation survey. RESULTS: Study participants (n =101) evaluated LSC as definitely/probably important for women (97.0%), helpful for making relationship decisions (86.2%), changing attitudes about having sex (79.2%), asking partners to use a condom (80.2%), leaving partners who won't use condoms (74.2%), handling oneself in tough situations in a relationship (79.2%), and getting an HIV test (83.2%). Participants liked/related to LSC and thought their friends would also like the series. CONCLUSIONS: Results indicated that young Hispanic women related to the video series, were likely to get HIV tested after watching the video series, found the story lines realistic, and thought their friends would like the series. The next step is to test the effectiveness of LSC to change behaviors of young Hispanic women at risk of HIV.


Assuntos
Infecções por HIV , Amor , Negro ou Afro-Americano , Feminino , Infecções por HIV/prevenção & controle , Hispânico ou Latino , Humanos , Estudantes , Adulto Jovem
9.
Biotechnol Bioeng ; 117(10): 2996-3005, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32579250

RESUMO

The use of microalgal biomass for metal pollutant bioremediation might be improved by genetic engineering to modify the selectivity or capacity of metal biosorption. A plant cadmium (Cd) and zinc (Zn) transporter (AtHMA4) was used as a transgene to increase the ability of Chlamydomonas reinhardtii to tolerate 0.2 mM Cd and 0.3 mM Zn exposure. The transgenic cells showed increased accumulation and internalization of both metals compared to wild-type. AtHMA4 was expressed either as the full-length (FL) protein or just the C-terminal (CT) tail, which is known to have metal-binding sites. Similar Cd and Zn tolerance and accumulation was observed with expression of either the FL protein or CT domain, suggesting that enhanced metal tolerance was mainly due to increased metal binding rather than metal transport. The effectiveness of the transgenic cells was further examined by immobilization in calcium alginate to generate microalgal beads that could be added to a metal contaminated solution. Immobilization maintained metal tolerance, while AtHMA4-expressing cells in alginate showed a concentration-dependent increase in metal biosorption that was significantly greater than alginate beads composed of wild-type cells. This demonstrates that expressing AtHMA4 FL or CT has great potential as a strategy for bioremediation using microalgal biomass.


Assuntos
Adenosina Trifosfatases/genética , Proteínas de Arabidopsis/genética , Bioacumulação , Cádmio/metabolismo , Chlamydomonas reinhardtii/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Transgenes , Zinco/metabolismo , Adenosina Trifosfatases/metabolismo , Proteínas de Arabidopsis/metabolismo , Biodegradação Ambiental , Transporte Biológico , Chlamydomonas reinhardtii/genética
10.
ACS Nano ; 12(6): 6273-6279, 2018 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-29873479

RESUMO

The development of innovative technologies to rapidly detect biomarkers associated with nutritional deficiencies in crops is highly relevant to agriculture and thus could impact the future of food security. Zinc (Zn) is an important micronutrient in plants, and deficiency leads to poor health, quality, and yield of crops. We have developed portable sensors, based on graphene oxide and upconversion nanoparticles, which could be used in the early detection of Zn deficiency in crops, sensing mRNAs encoding members of the ZIP-transporter family in crops. ZIPs are membrane transport proteins, some of which are up-regulated at the early stages of Zn deficiency, and they are part of the biological mechanism by which crops respond to nutritional deficiency. The principle of these sensors is based on the intensity of the optical output resulting from the interaction of oligonucleotide-coated upconversion nanoparticles and graphene oxide in the absence or presence of a specific oligonucleotide target. The sensors can reliably detect mRNAs in RNA extracts from plants using a smartphone camera. Our work introduces the development of accurate and highly sensitive sensors for use in the field to determine crop nutrient status and ultimately facilitate economically important nutrient management decisions.


Assuntos
Produtos Agrícolas/química , Produtos Agrícolas/metabolismo , Grafite/química , Nanopartículas/química , Zinco/deficiência , Oligonucleotídeos/química , Tamanho da Partícula , RNA Mensageiro/análise , Propriedades de Superfície , Zinco/análise
11.
J Plant Physiol ; 228: 158-165, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29933138

RESUMO

Nitrate uptake by plants is mediated by specific transport proteins in roots (NRTs), which are also dependent on the activity of proton pumps that energize the reaction. Nitrogen (N) metabolism in plants is sensitive to copper (Cu) toxicity conditions. To understand how Cu affects the uptake and assimilation processes, this study assesses the inhibitory effects of elevated Cu levels on the expression of genes related to N absorption, transport and assimilation in roots of Arabidopsis. Plants were grown hydroponically for 45 days, being exposed to a range of Cu concentrations in the last 72 h or alternatively exposed to 5.0 µM Cu for the last 15 days. High Cu levels decreased the uptake and accumulation of N in plants. It down-regulated the expression of genes encoding nitrate reductase (NR1), low-affinity nitrate transporters (NRT1 family) and bZIP transcription factors (TGA1 and TGA4) that regulate the expression of nitrate transporters. Cu toxicity also specifically down-regulated the plasma membrane proton pump, AHA2, whilst having little effect on AHA1 and AHA5. In contrast, there was an up-regulation of high-affinity nitrate transporters from the NRT2 family when exposed to medium level of Cu excess, but this was insufficient for restoring N absorption by roots to control levels. These results demonstrate that plants display specific responses to Cu toxicity, modulating the expression of particular genes related to nitrate uptake, such as low-affinity nitrate transporters and proton pumps.


Assuntos
Proteínas de Transporte de Ânions/metabolismo , Arabidopsis/metabolismo , Cobre/toxicidade , Nitratos/metabolismo , Arabidopsis/efeitos dos fármacos , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Nitrato Redutase/metabolismo , Transportadores de Nitrato , Bombas de Próton/metabolismo
12.
Physiol Plant ; 2018 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-29667213

RESUMO

Antioxidant enzymatic responses in Citrus leaves under Cu-induced stress depends on rootstock genotypes. However, there is a lack of information about how woody plants recover growth capacity after exposure to elevated Cu and whether growth is affected by the redistribution of the metal to new vegetative parts and consequently whether photosynthesis is affected. Therefore, the biomass of plants and Cu concentrations in new leaf flushes were determined in young citrus trees grafted onto contrasting rootstocks [Swingle citrumelo (SW) and Rangpur lime (RL)]. Photosynthetic rate, chlorophyll fluorescence and antioxidant enzymatic systems were evaluated in plants previously grown in nutrient solution with Cu varying from low to high levels and with no added Cu. Both rootstocks exhibited reduced plant growth under Cu toxicity. However, trees grafted onto RL exhibited better growth recovery after Cu excess, which was dependent on the modulation of antioxidant enzyme activities in roots and leaves that maintained the integrity of the photosynthetic apparatus. In contrast, plants grafted onto SW exhibited a lower photosynthetic rate at the lowest available Cu concentration. Although the highest accumulation of Cu occurred in citrus roots, the redistribution of the nutrient to new vegetative parts was proportional to the Cu concentration in the roots.

13.
Front Plant Sci ; 9: 185, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29503658

RESUMO

Tobacco has frequently been suggested as a candidate plant species for use in phytoremediation of metal contaminated soil but knowledge on the regulation of its metal-homeostasis is still in the infancy. To identify new tobacco metal transport genes that are involved in Zn homeostasis a bioinformatics study using the tobacco genome information together with expression analysis was performed. Ten new tobacco metal transport genes from the ZIP, NRAMP, MTP, and MRP/ABCC families were identified with expression levels in leaves that were modified by exposure to Zn excess. Following exposure to high Zn there was upregulation of NtZIP11-like, NtNRAMP3, three isoforms of NtMTP2, three MRP/ABCC genes (NtMRP5-like, NtMRP10-like, and NtMRP14 like) and downregulation of NtZIP1-like and NtZIP4. This suggests their involvement in several processes governing the response to Zn-related stress and in the efficiency of Zn accumulation (uptake, sequestration, and redistribution). Further detailed analysis of NtZIP1-like provided evidence that it is localized at the plasma membrane and is involved in Zn but not Fe and Cd transport. NtZIP1-like is expressed in the roots and shoots, and is regulated developmentally and in a tissue-specific manner. It is highly upregulated by Zn deficiency in the leaves and the root basal region but not in the root apical zone (region of maturation and absorption containing root hairs). Thus NtZIP1-like is unlikely to be responsible for Zn uptake by the root apical region but rather in the uptake by root cells within the already mature basal zone. It is downregulated by Zn excess suggesting it is involved in a mechanism to protect the root and leaf cells from accumulating excess Zn.

14.
Front Plant Sci ; 9: 1984, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30687374

RESUMO

Tobacco is frequently considered as a plant useful for phytoremediation of metal-contaminated soil, despite the mechanisms for regulation of uptake and accumulation being largely unknown. Here we cloned and characterized a new tobacco Zn and Cd transporter NtZIP4B from the ZIP family (ZRT-IRT-Like proteins). It complemented the Zn-uptake defective yeast mutant zrt1zrt2, and rendered the wild type DY1457 yeast more sensitive to Cd. Bioinformatic analysis and transient expression of the NtZIP4B-GFP fusion protein in tobacco leaves indicated its localization to the plasma membrane. Real-time q-PCR based analysis showed that it is expressed in all vegetative organs with the highest level in leaves. The Zn status determined transcript abundance; NtZIP4B was upregulated by Zn-deficiency and downregulated by Zn excess. At the tissue level, in roots NtZIP4B is expressed in the vasculature of the middle part of the roots and in surrounding tissues including the root epidermis; in leaves primarily in the vasculature. Bioinformatic analysis identified two copies of ZIP4 in tobacco, NtZIP4A and NtZIP4B with 97.57% homology at the amino acid level, with the same expression pattern for both, indicating a high degree of functional redundancy. Moreover, the present study provides new insights into the coordinated function of NtZIP1, NtZIP2, NtZIP4, NtZIP5, NtZIP8, NtIRT1, and NtIRT1-like in response to low-to-high Zn status. Leaves were the major site of NtZIP4, NtZIP5, and NtZIP8 expression, and roots for NtZIP1, NtZIP2, NtIRT1, and NtIRT1-like. Contrasting expression level in the apical and basal root parts indicates distinct roles in root-specific processes likely contributing to the regulation of Zn root-to-shoot translocation. In summary, new insight into the role of ZIP genes in Zn homeostasis pointing to their overlapping and complementary functions, offers opportunities for strategies to modify Zn and Cd root/shoot partition in tobacco.

15.
Sci Rep ; 7(1): 15258, 2017 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-29127328

RESUMO

Membrane transporters play a key role in obtaining sufficient quantities of manganese (Mn) but also in protecting against Mn toxicity. We have characterized OsMTP11, a member of the Cation Diffusion Facilitator/Metal Tolerance Protein (CDF/MTP) family of metal cation transporters in Oryza sativa. We demonstrate that OsMTP11 functions in alleviating Mn toxicity as its expression can rescue the Mn-sensitive phenotype of the Arabidopsis mtp11-3 knockout mutant. When expressed stably in Arabidopsis and transiently in rice and tobacco, it localises to the Golgi. OsMTP11 partially rescues the Mn-hypersensitivity of the pmr1 yeast mutant but only slightly alleviates the Zn sensitivity of the zrc1 cot1 yeast mutant. Overall, these results suggest that OsMTP11 predominantly functions as a Mn-transporting CDF with lower affinity for Zn. Site-directed mutagenesis studies revealed four substitutions in OsMTP11 that appear to alter its transport activity. OsMTP11 harbouring a substitution of leucine 150 to a serine fully rescued pmr1 Mn-sensitivity at all concentrations tested. The other substitutions, including those at conserved DxxxD domains, reduced complementation of pmr1 to different levels. This indicates their importance for OsMTP11 function and is a starting point for refining transporter activity/specificity.


Assuntos
Proteínas de Transporte de Cátions/metabolismo , Tolerância a Medicamentos , Complexo de Golgi/metabolismo , Manganês/farmacologia , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Transporte de Cátions/genética , Complexo de Golgi/genética , Transporte de Íons/genética , Oryza/genética , Proteínas de Plantas/genética
16.
BMC Plant Biol ; 17(1): 174, 2017 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-29078753

RESUMO

BACKGROUND: P2- type calcium ATPases (ACAs-auto inhibited calcium ATPases and ECAs-endoplasmic reticulum calcium ATPases) belong to the P- type ATPase family of active membrane transporters and are significantly involved in maintaining accurate levels of Ca2+, Mn2+ and Zn2+ in the cytosol as well as playing a very important role in stress signaling, stomatal opening and closing and pollen tube growth. Here we report the identification and possible role of some of these ATPases from wheat. RESULTS: In this study, ACA and ECA sequences of six species (belonging to Poaceae) were retrieved from different databases and a phylogenetic tree was constructed. A high degree of evolutionary relatedness was observed among P2 sequences characterized in this study. Members of the respective groups from different plant species were observed to fall under the same clade. This pattern highlights the common ancestry of P2- type calcium ATPases. Furthermore, qRT-PCR was used to analyse the expression of selected ACAs and ECAs from Triticum aestivum (wheat) under calcium toxicity and calcium deficiency. The data indicated that expression of ECAs is enhanced under calcium stress, suggesting possible roles of these ATPases in calcium homeostasis in wheat. Similarly, the expression of ACAs was significantly different in plants grown under calcium stress as compared to plants grown under control conditions. This gives clues to the role of ACAs in signal transduction during calcium stress in wheat. CONCLUSION: Here we concluded that wheat genome consists of nine P2B and three P2A -type calcium ATPases. Moreover, gene loss events in wheat ancestors lead to the loss of a particular homoeolog of a gene in wheat. To elaborate the role of these wheat ATPases, qRT-PCR was performed. The results indicated that when plants are exposed to calcium stress, both P2A and P2B gene expression get enhanced. This further gives clues about the possible role of these ATPases in wheat in calcium management. These findings can be useful in future for genetic manipulations as well as in wheat genome annotation process.


Assuntos
ATPases Transportadoras de Cálcio/genética , Proteínas de Plantas/genética , Triticum/genética , Cálcio/metabolismo , Retículo Endoplasmático/enzimologia , Estudo de Associação Genômica Ampla , Manganês/metabolismo , Filogenia , Proteínas de Plantas/metabolismo , Proteínas de Plantas/fisiologia , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA , Estresse Fisiológico/fisiologia , Triticum/enzimologia , Triticum/metabolismo , Zinco/metabolismo
17.
Plant J ; 92(2): 291-304, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28771859

RESUMO

Understanding the molecular basis of zinc (Zn) uptake and transport in staple cereal crops is critical for improving both Zn content and tolerance to low-Zn soils. This study demonstrates the importance of group F bZIP transcription factors and ZIP transporters in responses to Zn deficiency in wheat (Triticum aestivum). Seven group F TabZIP genes and 14 ZIPs with homeologs were identified in hexaploid wheat. Promoter analysis revealed the presence of Zn-deficiency-response elements (ZDREs) in a number of the ZIPs. Functional complementation of the zrt1/zrt2 yeast mutant by TaZIP3, -6, -7, -9 and -13 supported an ability to transport Zn. Group F TabZIPs contain the group-defining cysteine-histidine-rich motifs, which are the predicted binding site of Zn2+ in the Zn-deficiency response. Conservation of these motifs varied between the TabZIPs suggesting that individual TabZIPs may have specific roles in the wheat Zn-homeostatic network. Increased expression in response to low Zn levels was observed for several of the wheat ZIPs and bZIPs; this varied temporally and spatially suggesting specific functions in the response mechanism. The ability of the group F TabZIPs to bind to specific ZDREs in the promoters of TaZIPs indicates a conserved mechanism in monocots and dicots in responding to Zn deficiency. In support of this, TabZIPF1-7DL and TabZIPF4-7AL afforded a strong level of rescue to the Arabidopsis hypersensitive bzip19 bzip23 double mutant under Zn deficiency. These results provide a greater understanding of Zn-homeostatic mechanisms in wheat, demonstrating an expanded repertoire of group F bZIP transcription factors, adding to the complexity of Zn homeostasis.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/fisiologia , Proteínas de Membrana Transportadoras/fisiologia , Triticum/metabolismo , Zinco/deficiência , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/fisiologia , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Regulação da Expressão Gênica de Plantas/fisiologia , Genes de Plantas/fisiologia , Proteínas de Membrana Transportadoras/metabolismo , Filogenia , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas/fisiologia , Triticum/genética , Triticum/fisiologia , Zinco/metabolismo
18.
Plant Cell Environ ; 40(11): 2754-2770, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28763829

RESUMO

Zinc (Zn) deficiency negatively impacts the development and health of plants and affects crop yield. When experiencing low Zn, plants undergo an adaptive response to maintain Zn homeostasis. We provide further evidence for the role of F-group transcription factors, AtbZIP19 and AtbZIP23, in responding to Zn deficiency in Arabidopsis and demonstrate the sensitivity and specificity of this response. Despite their economic importance, the role of F-group bZIPs in cereal crops is largely unknown. Here, we provide new insights by functionally characterizing these in barley (Hordeum vulgare), demonstrating an expanded number of F-group bZIPs (seven) compared to Arabidopsis. The F-group barley bZIPs, HvbZIP56 and HvbZIP62, partially rescue the Zn-dependent growth phenotype and ZIP-transporter gene regulation of an Arabidopsis bzip19-4 bzip23-2 mutant. This supports a conserved mechanism of action in adapting to Zn deficiency. HvbZIP56 localizes to the cytoplasm and nucleus when expressed in Arabidopsis and tobacco. Promoter analysis demonstrates that the barley ZIP transporters that are upregulated under Zn deficiency contain cis Zn-deficiency response elements (ZDREs). ZDREs are also found in particular barley bZIP promoters. This study represents a significant step forward in understanding the mechanisms controlling Zn responses in cereal crops, and will aid in developing strategies for crop improvement.


Assuntos
Hordeum/metabolismo , Proteínas de Plantas/metabolismo , Zinco/deficiência , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Clonagem Molecular , Regulação da Expressão Gênica de Plantas , Proteínas de Fluorescência Verde/metabolismo , Hidroponia , Micronutrientes/metabolismo , Mutação/genética , Motivos de Nucleotídeos/genética , Fenótipo , Filogenia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas , Transporte Proteico , Frações Subcelulares/metabolismo
19.
BMJ Open ; 7(2): e011745, 2017 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-28183806

RESUMO

OBJECTIVE: The Health and Social Care Act 2012 ('HSCA 2012') introduced a new, statutory, form of regulation of competition into the National Health Service (NHS), while at the same time recognising that cooperation was necessary. NHS England's policy document, The Five Year Forward View ('5YFV') of 2014 placed less emphasis on competition without altering the legislation. We explored how commissioners and providers understand the complex regulatory framework, and how they behave in relation to competition and cooperation. DESIGN: We carried out detailed case studies in four clinical commissioning groups, using interviews and documentary analysis to explore the commissioners' and providers' understanding and experience of competition and cooperation. SETTING/PARTICIPANTS: We conducted 42 interviews with senior managers in commissioning organisations and senior managers in NHS and independent provider organisations (acute and community services). RESULTS: Neither commissioners nor providers fully understand the regulatory regime in respect of competition in the NHS, and have not found that the regulatory authorities have provided adequate guidance. Despite the HSCA 2012 promoting competition, commissioners chose mainly to use collaborative strategies to effect major service reconfigurations, which is endorsed as a suitable approach by providers. Nevertheless, commissioners are using competitive tendering in respect of more peripheral services in order to improve quality of care and value for money. CONCLUSIONS: Commissioners regard the use of competition and cooperation as appropriate in the NHS currently, although collaborative strategies appear more helpful in respect of large-scale changes. However, the current regulatory framework contained in the HSCA 2012, particularly since the publication of the 5YFV, is not clear. Better guidance should be issued by the regulatory authorities.


Assuntos
Atitude do Pessoal de Saúde , Reforma dos Serviços de Saúde/métodos , Medicina Estatal/legislação & jurisprudência , Humanos , Entrevistas como Assunto , Pesquisa Qualitativa , Medicina Estatal/organização & administração , Reino Unido
20.
J Health Organ Manag ; 29(6): 778-94, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26394257

RESUMO

PURPOSE: The purpose of this paper is to explore government efforts to enhance the autonomy of community health services (CHS) in England through the creation of Foundation Trusts status. It considers why some CHS elected to become nascent Community Foundation Trusts (CFTs) while others had not and what advantages they thought increased levels of autonomy offered. DESIGN/METHODOLOGY/APPROACH: Data are drawn from the evaluation of the Department of Health's CFT pilot programme. Participants were purposively selected from pilot sites, as well as from comparator non-pilot organisations. A total of 44 staff from 14 organisations were interviewed. FINDINGS: The data reveals that regardless of the different pathways that organisations were on, they all shared the same goal, a desire for greater autonomy, but specifically within the NHS. Additionally, irrespective of their organisational form most organisations were considering an almost identical set of initiatives as a means to improve service delivery and productivity. RESEARCH LIMITATIONS/IMPLICATIONS: Despite the expectations of policy makers no CFTs were established during the course of the study, so it is not possible to find out what the effect of such changes were. Nevertheless, the authors were able to investigate the attitudes of all the providers of CHS to the plans to increase their managerial autonomy, whether simply by separating from PCTs or by becoming CFTs. ORIGINALITY/VALUE: As no CFTs have yet been formed, this study provides the only evidence to date about increasing autonomy for CHS in England.


Assuntos
Serviços de Saúde Comunitária/organização & administração , Autonomia Profissional , Medicina Estatal/organização & administração , Serviços de Saúde Comunitária/economia , Serviços de Saúde Comunitária/tendências , Controle de Custos/métodos , Controle de Custos/normas , Inglaterra , Humanos , Medicina Estatal/economia , Medicina Estatal/tendências
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