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Grape breeding programs are mostly focused on developing new varieties with high production volume, sugar contents, and phenolic compound diversity combined with resistance and tolerance to the main pathogens under culture and adverse environmental conditions. The 'Niagara' variety (Vitis labrusca × Vitis vinifera) is one of the most widely produced and commercialized table grapes in Brazil. In this work, we selected three Niagara somatic variants with contrasting berry phenotypes and performed morphological and transcriptomic analyses of their berries. Histological sections of the berries were also performed to understand anatomical and chemical composition differences of the berry skin between the genotypes. An RNA-Seq pipeline was implemented, followed by global coexpression network modeling. 'Niagara Steck', an intensified russet mutant with the most extreme phenotype, showed the largest difference in expression and showed selection of coexpressed network modules involved in the development of its russet-like characteristics. Enrichment analysis of differently expressed genes and hub network modules revealed differences in transcription regulation, auxin signaling and cell wall and plasmatic membrane biogenesis. Cutin- and suberin-related genes were also differently expressed, supporting the anatomical differences observed with microscopy.
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Vitis , Vitis/metabolismo , Melhoramento Vegetal , Perfilação da Expressão Gênica , Frutas/metabolismo , BrasilRESUMO
Despite the use of digital communication technologies in neurocognitive rehabilitation has been widely used in face-to-face interventions, the difficulties of using ICT-based tools to provide rehabilitation services and the unfamiliarity of the neuropsychologists with internet interventions limited the use of these kinds of interventions in their clinical practices. The lockdown and mitigating measures associated with the COVID-19 pandemic, on the other hand, forced the use of at-distance and online interventions as a means to mitigate the impact of those measures on the mental health and rehabilitation processes of people with neurological disorders. Overall, little is known about the perspectives of patients with acquired neurological conditions about rehabilitation services delivered at distance. Therefore, the main goal of this study was to explore the perceptions that patients with neurological disorders have on at-distance online neurocognitive rehabilitation, namely during the COVID-19 pandemic. Sixteen patients with acquired neurological conditions attending an online neurocognitive rehabilitation program in a Portuguese rehabilitation center filled in an online questionnaire during the mandatory lockdown. The results of this study highlight the potential of delivering rehabilitation services at distance, presenting its advantages and limitations from patients' perspectives, as well as suggestions for improving both neurorehabilitation processes and the online rehabilitation platform used.
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Objective: The study aimed to evaluate whether a pilot communication rehabilitation programme improves different communicative modalities in people who have sustained a moderate to severe TBI immediately following the training and at 3 months follow up.Methods: We have recruited 12 participants who had moderate-to-severe TBI. Subjects were randomly divided into two groups, EG and CG. We have assessed the groups before and after treatment and we have performed a follow-up three months later, through of the ABaCo. The EG followed a very structured programme. In the CG, a programme to stimulate communication through free conversation was carried out. Each programme consisted of 24 group sessions, of 1h30 min, twice a week, for 12 weeks.Results: Improvements were observed in both groups, although more evident in the EG. Both groups had better results in extralinguistic production. In the EG, there was still an improvement in the paralinguistic production and extralinguistic comprehension, after ending the training. These improvements persisted 3 months after ending the programme.Conclusion: The results demonstrated the effectiveness of the intervention of a structured pragmatic rehabilitation programme. However, the existence of a communication group based solely on conversation can also have positive results and should be implemented whenever a more specific intervention is not possible. In future research, it will be important to increase the sample size and involve caregivers in person and regularly in the EG programme.
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Lesões Encefálicas Traumáticas , Cuidadores , Comunicação , Compreensão , Humanos , Projetos PilotoRESUMO
In this work, several attributes of the internal morphology of drupaceous fruits found in the archaeological site Monte Castelo (Rondonia, Brazil) are analyzed by means of two different imaging methods. The aim is to explore similarities and differences in the visualization and analytical properties of the images obtained via High Resolution Light Microscopy and X-ray micro-computed tomography (X-ray MicroCT) methods. Both provide data about the three-layered pericarp (exo-, meso- and endocarp) of the studied exemplars, defined by cell differentiation, vascularisation, cellular contents, presence of sclerenchyma cells and secretory cavities. However, it is possible to identify a series of differences between the information that can be obtained through each of the methods. These variations are related to the definition of contours and fine details of some characteristics, their spatial distribution, size attributes, optical properties and material preservation. The results obtained from both imaging methods are complementary, contributing to a more exhaustive morphological study of the plant remains. X-ray MicroCT in phase-contrast mode represents a suitable non-destructive analytic technique when sample preservation is required.
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Frutas/fisiologia , Imageamento Tridimensional/métodos , Olea/fisiologia , Microtomografia por Raio-X/métodos , Brasil , Frutas/anatomia & histologia , Microscopia de Contraste de Fase , Olea/anatomia & histologiaRESUMO
ABSTRACT Purpose: to perform the transcultural adaptation and translation of the ABaCo battery for the Portuguese population and check its psychometric properties. Methods: initially, the translation and retroversion of ABaCo was done. A total of 40 participants without pathology were recruited. Two equivalent Forms (Form A and Form B) were used, consisting of linguistic, extralinguistic, paralinguistic and context scales. The instrument was also applied to 12 people who were in the chronic phase after severe or moderate traumatic brain injury (TBI). For statistical analysis the following tests were used: Mann-Whitney U test, Student t test for independent samples, Pearson's correlation (the value is considered significant when p ≤ 0.05) and Cronbach's alpha (the value is considered minimally acceptable when superior to 0.65). Results: TBIs' participants showed lower results as compared to those without neurological pathology. The evidence was discriminatory for the population with TBI, although, on some scales, it was not, due to the ceiling effect. Differences were not found between the two Forms. The results also showed the existence of correlation of schooling and age with some of the components of ABaCo, as verified in the original version. No differences in gender-conditioned responses were found. The battery showed good metrical qualities with a Cronbach's alpha of 0.90 (Form A) and 0.71 (Form B), for the total sample. Conclusion: ABaCo has proved to be an appropriate instrument for assessing communication in the Portuguese adult population. Despite the limitations, this instrument is expected to be useful in the evaluation of the communication, following TBI.
RESUMO Objetivo: realizar a tradução e adaptação transcultural da bateria ABaCo para a população portuguesa e verificar as suas propriedades psicométricas. Métodos: foi realizada a tradução e retroversão da ABaCo. Foram recrutados 40 participantes sem patologia. Foram utilizadas as duas Formas equivalentes (Forma A e B), constituídas por quatro escalas: linguística, extralinguística, paralinguística e de contexto. A prova foi também aplicada a 12 pessoas que se encontravam na fase crónica após traumatismo crânio-encefálico (TCE) grave ou moderado. Para análise estatística foram utilizados os seguintes testes: Mann-Whitney U test, teste t de Student para amostras independentes, a correlação de Pearson (o valor é considerado significante se p ≤ 0.05) e o alpha de Cronbach (o valor é considerado minimamente aceitável se for superior a 0.65). Resultados: os TCE apresentaram resultados mais baixos, comparativamente a população sem patologia neurológica. A prova mostrou ser discriminativa para a população com TCE, embora em algumas escalas tal fato não aconteça, devido ao ceiling effect. Verificou-se não haver diferenças entre as duas Formas. Os resultados mostraram, ainda, a existência de correlação da escolaridade e da idade com algumas das componentes da ABaCo, tal como se verificou na versão original. Não foram verificadas diferenças nas respostas condicionadas pelo gênero. A bateria mostrou ter boas qualidades métricas, com um alpha de Cronbach de 0.90 (Forma A) e de 0.71 (Forma B) para a amostra total. Conclusão: a ABaCo mostrou ser um instrumento adequado para avaliação da comunicação na população adulta portuguesa. Apesar das limitações, é esperado que esta prova seja útil na avaliação da comunicação em indivíduos acometidos por TCE.
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Introdução: Para o estudo das emoções têm-se utilizado técnicas de autorrelato, nomeadamente, as escalas de valência e de arousal do Self-Assessment Manikin (SAM), que proporcionam uma apreciação cognitiva subjetiva das diferentes dimensões emocionais. No entanto, é legítimo equacionar que esta capacidade de avaliação cognitiva possa estar alterada em pacientes com lesão encefálica adquirida (LEA). Consequentemente, pode haver incongruência na avaliação das suas respostas emocionais. Assim, a avaliação deve incluir outras técnicas complementares, como são as medidas fisiológicas periféricas empiricamente validadas para o estudo das emoções. Métodos: Avaliamos 36 pacientes com LEA em referência a 33 participantes saudáveis. Ambos os grupos observaram imagens agradáveis, desagradáveis e neutras selecionadas do International Affective Picture System (IAPS), que tinham de classificar através das escalas de valência e de arousal do SAM, enquanto eram registadas as suas respostas fisiológicas periféricas: condutância elétrica da pele (CEP) e ritmo cardíaco (RC). Resultados: Nas técnicas de autorrelato, os pacientes com LEA fazem uma avaliação da valência diferente, independentemente dos estímulos, em relação aos controles. Já quando consideramos a escala de arousal os pacientes sentem-se mais ativados do que os controles, exceto nos estímulos desagradáveis. Contudo, os resultados obtidos na medição objetiva dos seus correlatos fisiológicos não são congruentes com a avaliação cognitiva que realizam, uma vez que mostraram menor reatividade aos estímulos independentemente da sua condição emocional. Conclusão: Estes resultados mostram que indivíduos com LEA têm dificuldade em fazer uma avaliação coerente do seu estado de ativação fisiológico. Por essa razão, é altamente recomendado o uso simultâneo de medidas psicofisiológicas.(AU)
Introduction: Self-report measures have been used in the study of emotions, namely the valence and arousal scales of the Self-Assessment Manikin (SAM), which provide a subjective cognitive appraisal of different emotional dimensions. However, cognitive assessment ability in patients with acquired brain injury (ABI) may be compromised. Consequently, their emotional responses measured by self-report may be inconsistent. In these cases, the assessment should include complementary techniques, such as peripheral physiological measures empirically validated for the study of emotions. Method: We evaluated 36 patients with ABI and 33 healthy controls. Both groups watched pleasant, unpleasant and neutral images from the International Affective Picture System (IAPS) and rated them using SAM valence and arousal scales, while their peripheral physiological responses, consisting of skin conductance response (SCR) and heart rate (HR), were recorded. Results: In self-report measures, patients with ABI evaluated valence differently, regardless of stimuli, compared to controls. Regarding the arousal scale, patients with ABI reported feeling more aroused when compared to controls, except in unpleasant stimuli. However, the results obtained in the physiological assessment are not consistent with those of the cognitive assessment, as they showed lower reactivity to stimuli regardless of their emotional condition. Conclusion: These results show that patients with ABI have more difficulty in making a coherent assessment of their physiological arousal. For this reason, the simultaneous use of psychophysiological measures is highly recommended. (AU)
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Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/psicologia , Autoavaliação (Psicologia) , Cognição , Emoções , Autoavaliação Diagnóstica , AutorrelatoRESUMO
Flowers of Anacardiaceae and other Sapindales typically produce nectar, but scent, often associated with a reward for pollinators, has surprisingly been mentioned only rarely for members of the family and order. However, flowers of Anacardium humile and Mangifera indica produce a strong sweet scent. The origin and composition of these floral scents is the subject of this study. Screening of potential osmophores on the petals and investigations of their anatomy were carried out by light, scanning and transmission electron microscopy. The composition of the floral fragrance was characterized by gas chromatography-mass spectrometry. In both species, the base of the adaxial side of each petal revealed specialized secretory epidermal cells which are essentially similar in structure and distinct from all other neighbouring cells. These cells also showed evidence of granulocrine secretory mechanisms and slight specific variations in their subcellular apparatus coinciding with the respective composition of the floral fragrance, predominantly composed of sesquiterpenes in A. humile and monoterpenes in M. indica. This study reports the presence of osmophores for the first time in flowers of Anacardiaceae and confirms the link between the ultrastructural features of their secretory cells and the volatiles produced by the flowers. The flowers of most Sapindales, including Anacardiaceae, are nectariferous. However, the presence of osmophores has only been described for very few genera of Rutaceae and Sapindaceae. Both the occurrence of osmophores and fragrance may have largely been overlooked in Anacardiaceae and Sapindales until now. Further studies are needed to better understand the nature and diversity of the interactions of their nectariferous flowers with their pollinators.
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The purpose of this study is to present an fMRI paradigm, based on the Williams inhibition test (WIT), to study attentional and inhibitory control and their neuroanatomical substrates. We present an index of the validity of the proposed paradigm and test whether the experimental task discriminates the behavioral performances of healthy participants from those of individuals with acquired brain injury. Stroop and Simon tests present similarities with WIT, but this latter is more demanding. We analyze the BOLD signal in 10 healthy participants performing the WIT. The dorsolateral prefrontal cortex, the inferior prefrontal cortex, the anterior cingulate cortex, and the posterior cingulate cortex were defined for specified region of interest analysis. We additionally compare behavioral data (hits, errors, reaction times) of the healthy participants with those of eight acquired brain injury patients. Data were analyzed with GLM-based random effects and Mann-Whitney tests. Results show the involvement of the defined regions and indicate that the WIT is sensitive to brain lesions. This WIT-based block design paradigm can be used as a research methodology for behavioral and neuroimaging studies of the attentional and inhibitory components of executive functions.
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Atenção/fisiologia , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Inibição Psicológica , Imageamento por Ressonância Magnética , Testes Neuropsicológicos , Adulto , Encéfalo/fisiopatologia , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Lesões Encefálicas Traumáticas/fisiopatologia , Lesões Encefálicas Traumáticas/psicologia , Mapeamento Encefálico , Circulação Cerebrovascular/fisiologia , Função Executiva/fisiologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Oxigênio/sangue , Tempo de Reação , Autocontrole , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/psicologiaRESUMO
The goal of this study was to propose a new functional magnetic resonance imaging (fMRI) paradigm using a language-free adaptation of a 2-back working memory task to avoid cultural and educational bias. We additionally provide an index of the validity of the proposed paradigm and test whether the experimental task discriminates the behavioural performances of healthy participants from those of individuals with working memory deficits. Ten healthy participants and nine patients presenting working memory (WM) deficits due to acquired brain injury (ABI) performed the developed task. To inspect whether the paradigm activates brain areas typically involved in visual working memory (VWM), brain activation of the healthy participants was assessed with fMRIs. To examine the task's capacity to discriminate behavioural data, performances of the healthy participants in the task were compared with those of ABI patients. Data were analysed with GLM-based random effects procedures and t-tests. We found an increase of the BOLD signal in the specialized areas of VWM. Concerning behavioural performances, healthy participants showed the predicted pattern of more hits, less omissions and a tendency for fewer false alarms, more self-corrected responses, and faster reaction times, when compared with subjects presenting WM impairments. The results suggest that this task activates brain areas involved in VWM and discriminates behavioural performances of clinical and non-clinical groups. It can thus be used as a research methodology for behavioural and neuroimaging studies of VWM in block-design paradigms.
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Mapeamento Encefálico , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Memória de Curto Prazo/fisiologia , Processamento Espacial/fisiologia , Adulto , Discriminação Psicológica , Feminino , Humanos , Imageamento Tridimensional , Masculino , Testes Neuropsicológicos , Oxigênio/sangue , Estimulação Luminosa , Adulto JovemRESUMO
Sugarcane (Saccharum spp.) is currently one of the most efficient crops in the production of first-generation biofuels. However, the bagasse represents an additional abundant lignocellulosic resource that has the potential to increase the ethanol production per plant. To achieve a more efficient conversion of bagasse into ethanol, a better understanding of the main factors affecting biomass recalcitrance is needed. Because several studies have shown a negative effect of lignin on saccharification yield, the characterization of lignin biosynthesis, structure, and deposition in sugarcane is an important goal. Here, we present, to our knowledge, the first systematic study of lignin deposition during sugarcane stem development, using histological, biochemical, and transcriptional data derived from two sugarcane genotypes with contrasting lignin contents. Lignin amount and composition were determined in rind (outer) and pith (inner) tissues throughout stem development. In addition, the phenolic metabolome was analyzed by ultra-high-performance liquid chromatography-mass spectrometry, which allowed the identification of 35 compounds related to the phenylpropanoid pathway and monolignol biosynthesis. Furthermore, the Sugarcane EST Database was extensively surveyed to identify lignin biosynthetic gene homologs, and the expression of all identified genes during stem development was determined by quantitative reverse transcription-polymerase chain reaction. Our data provide, to our knowledge, the first in-depth characterization of lignin biosynthesis in sugarcane and form the baseline for the rational metabolic engineering of sugarcane feedstock for bioenergy purposes.
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Regulação da Expressão Gênica de Plantas , Estudos de Associação Genética , Lignina/metabolismo , Saccharum/genética , Saccharum/metabolismo , Teorema de Bayes , Vias Biossintéticas/genética , Perfilação da Expressão Gênica , Genes de Plantas/genética , Genótipo , Lignina/biossíntese , Lignina/química , Fenóis/metabolismo , Caules de Planta/citologia , Caules de Planta/genética , Caules de Planta/crescimento & desenvolvimento , Caules de Planta/metabolismo , Análise de Componente Principal , SolubilidadeRESUMO
Objetivou-se, neste trabalho, estudar a influência do lactato de cálcio e do tipo de açúcar nas propriedades mecânicas e na estrutura celular de pedaços de melão desidratados osmoticamente. O processo foi conduzido por duas horas com agitação de 120 rpm e temperatura controlada (30º C), utilizando-se soluções desidratantes de sacarose ou maltose a 40ºBrix, contendo lactato de cálcio em concentrações de 0, 0,5, 1,0 e 1,5 por cento (p/v). As amostras foram submetidas às determinações de perda de água, ganho de sólidos, incorporação de cálcio, propriedades mecânicas (tensão e deformação na ruptura) e microscopia óptica. Os ensaios com maltose, em ação conjunta com o sal, promoveram uma maior perda de água e um menor ganho de sólidos. A adição de lactato de cálcio na solução osmótica de sacarose ou maltose resultou em maiores valores de tensão na ruptura para as frutas, sendo que tal aumento foi mais pronunciado nos ensaios com sacarose, devido à maior incorporação de cálcio observada nesses tratamentos. O lactato de cálcio mostrou-se eficiente na preservação da estrutura celular das amostras, quando utilizado em concentrações de até 1,0 por cento. A maltose apresentou um maior efeito protetor na manutenção da funcionalidade da membrana celular, enquanto que o processo realizado apenas com soluções de sacarose, assim como os ensaios realizados com concentração de sal igual a 1,5 por cento provocaram danos na parede celular e intensa plasmólise do citoplasma.
The purpose of this work was to study the influence of calcium lactate and sugar type on mechanical properties and cellular structure of osmodehydrated melon pieces. The process was carried out for two hours under controlled temperature (30º C) and agitation (120 rpm), using a 40ºBrix sucrose or maltose solution containing calcium lactate (0 to 2,0 percent). Samples were analyzed with respect to water loss, solids and calcium gain, mechanical properties (stress and strain at rupture) and structure by light microscopy. Maltose treatments in combination with the salt action promoted higher water loss and lower solids gain rates. The calcium lactate addition in the sucrose or maltose solution resulted in higher stress at rupture values. This increase was more pronounced for sucrose treatments, due to the higher calcium uptake observed in these experiments. Calcium lactate was efficient in the maintenance of melon cellular structure when used at concentrations up to 1,0 percent. Maltose showed a higher protector effect in cellular membrane functionality, while the treatment performed only with sucrose solution as well as both treatments with salt concentration at 1,5 percentcaused an intense cytoplasm plasmolysis and cell wall damages.
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The characterization of a coffee gene encoding a protein similar to miraculin-like proteins, which are members of the plant Kunitz serine trypsin inhibitor (STI) family of proteinase inhibitors (PIs), is described. PIs are important proteins in plant defence against insects and in the regulation of proteolysis during plant development. This gene has high identity with the Richadella dulcifica taste-modifying protein miraculin and with the tomato protein LeMir; and was named as CoMir (Coffea miraculin). Structural protein modelling indicated that CoMir had structural similarities with the Kunitz STI proteins, but suggested specific folding structures. CoMir was up-regulated after coffee leaf miner (Leucoptera coffella) oviposition in resistant plants of a progeny derived from crosses between C. racemosa (resistant) and C. arabica (susceptible). Interestingly, this gene was down-regulated during coffee leaf miner herbivory in susceptible plants. CoMir expression was up-regulated after abscisic acid application and wounding stress and was prominent during the early stages of flower and fruit development. In situ hybridization revealed that CoMir transcripts accumulated in the anther tissues that display programmed cell death (tapetum, endothecium and stomium) and in the metaxylem vessels of the petals, stigma and leaves. In addition, the recombinant protein CoMir shows inhibitory activity against trypsin. According to the present results CoMir may act in proteolytic regulation during coffee development and in the defence against L. coffeella. The similarity of CoMir with other Kunitz STI proteins and the role of CoMir in plant development and plant stress are discussed.
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Café/genética , Café/parasitologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas/genética , Glicoproteínas/genética , Mariposas/fisiologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Southern Blotting , Café/citologia , Café/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento , Modelos Moleculares , Dados de Sequência Molecular , Especificidade de Órgãos/genética , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Processamento de Proteína Pós-Traducional , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNARESUMO
The effect of calcium lactate on osmodehydrated guavas in sucrose and maltose solutions was monitored during storage under passive modified atmosphere for 24 d at 5 °C. Sample texture and color characteristics, microbial spoilage, sensory acceptance, structural changes, and gas composition inside the packages were periodically evaluated. Calcium lactate inhibited microbial growth on guavas, with yeast and mold counts in the order of 10(2) CFU/g throughout storage. The calcium salt reduced respiration rate of guava products, showing O(2) and CO(2) concentrations around 18% and 3% inside the packages. A firming effect on fruit texture, with up to 5 and 2 times higher stress and strain at failure values and tissue structure preservation could also be attributed to calcium lactate use. However, fruits treated with calcium lactate, osmodehydrated in maltose and sucrose solutions, showed sensory acceptance scores below the acceptability limit (4.5) after 13 and 17 d of storage, respectively.
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Anti-Infecciosos/farmacologia , Compostos de Cálcio/farmacologia , Microbiologia de Alimentos , Conservação de Alimentos , Frutas/efeitos dos fármacos , Lactatos/farmacologia , Psidium/efeitos dos fármacos , Dióxido de Carbono/análise , Contagem de Colônia Microbiana , Contaminação de Alimentos/análise , Embalagem de Alimentos , Frutas/microbiologia , Concentração de Íons de Hidrogênio , Oxigênio/análise , Pigmentação/efeitos dos fármacos , Psidium/microbiologia , Salmonella/crescimento & desenvolvimento , Salmonella/patogenicidadeRESUMO
Sucrose metabolism and the role of sucrose synthase were investigated in the fruit tissues (pericarp, perisperm, and endosperm) of Coffea arabica during development. Acid invertase, sucrose phosphate synthase, and sucrose synthase activities were monitored and compared with the levels of sucrose and reducing sugars. Among these enzymes, sucrose synthase showed the highest activities during the last stage of endosperm and pericarp development and this activity paralleled closely the accumulation of sucrose in these tissues at this stage. Carbon partitioning in fruits was studied by pulse-chase experiments with (14)C-sugars and revealed high rates of sucrose turnover in perisperm and endosperm tissues. Additional feeding experiments with (14)CO(2) showed that leaf photosynthesis contributed more to seed development than the pericarp in terms of photosynthate supply to the endosperm. Sugar analysis, feeding experiments, and histological studies indicated that the perisperm plays an important role in this downloading process. It was observed that the perisperm presents a transient accumulation of starch which is degraded as the seed develops. Two full-length cDNAs (CaSUS1 and CaSUS2) and the complete gene sequence of the latter were also isolated. They encode sucrose synthase isoforms that are phylogenetically distinct, indicating their involvement in different physiological functions during cherry development. Contrasting expression patterns were observed for CaSUS1 and CaSUS2 in perisperm, endosperm, and pericarp tissues: CaSUS1 mRNAs accumulated mainly during the early development of perisperm and endosperm, as well as during pericarp growing phases, whereas those of CaSUS2 paralleled sucrose synthase activity in the last weeks of pericarp and endosperm development. Taken together, these results indicate that sucrose synthase plays an important role in sugar metabolism during sucrose accumulation in the coffee fruit.
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Coffea/metabolismo , Frutas/metabolismo , Genoma de Planta , Sacarose/metabolismo , Transporte Biológico , Southern Blotting , Carbono/metabolismo , Dióxido de Carbono/metabolismo , Radioisótopos de Carbono , Coffea/genética , Coffea/crescimento & desenvolvimento , Frutose/metabolismo , Frutas/genética , Frutas/crescimento & desenvolvimento , Genômica , Glucosiltransferases/classificação , Glucosiltransferases/metabolismo , Glucosiltransferases/fisiologia , Dados de Sequência Molecular , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , RNA Mensageiro/metabolismo , beta-Frutofuranosidase/metabolismoRESUMO
O fruto de Lithraea molleoides (Vell.) Engl. é uma drupa globosa, branca-acinzentada, lisa, com exocarpo friável e lignificado quando maduro. O mesocarpo é parenquimático com grandes canais secretores associados aos feixes vasculares. O endocarpo é composto de quatro camadas: na camada mais externa as células são poliédricas, com cristais prismáticos de oxalato de cálcio, e nas três camadas internas as células são esclereides em paliçada. O envoltório da semente é membranáceo, liso, amarelo-pálido com uma mancha marrom escura. O óvulo é anátropo, unitegumentado, crassinucelado, inserido em posição basal-lateral. O funículo é crasso e cresce em direção à micrópila formando o obturador funicular. Na região calazal uma zona com células parenquimáticas de conteúdo tanífero formam a hipóstase. A semente em desenvolvimento apresenta uma forma circinótropa, originada a partir da curvatura do funículo crasso e longo que circunda o tegumento e o saco embrionário. A semente madura é endotestal com as paredes das células da endotesta espessadas e lignificadas em forma de barras ou pontuações.