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1.
Braz J Biol ; 84: e281793, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39109722

RESUMO

Genipa americana (Rubiaceae) is a fruit tree with broad phytogeographic domain and suitable for different silvicultural systems in the tropics. The knowledge associated with the relative growth rate of species such as G. americana, provides important guidelines for the effective establishment and survival of seedlings after planting in the field. In this study we investigated differences in growth, biomass allocation and photosynthesis of seedlings originating from different mother plants of G. americana in southern Bahia, Brazil. For this, we evaluated fifteen variables associated with carbon balance at the whole plant and leaf scales of twelve G. americana progenies. All seedlings grew over a period of 198 days under similar microclimatic conditions with approximately 65% full sun. Our results showed significant differences in the relative growth rates (RGR), with the highest and lowest mean values being 29.0 and 38.0 mg g-1 day-1, respectively. Differences in RGR between G. americana progenies were highly related to differences in biomass allocation at both whole plant and leaf scales. From a practical point of view, we demonstrate that the selection of mother plants to produce seedlings with higher growth rates, and consequently greater establishment capacity in field plantings, can be made from evaluations of growth and biomass allocation variables at the whole plant scale.


Assuntos
Biomassa , Fotossíntese , Folhas de Planta , Rubiaceae , Plântula , Folhas de Planta/crescimento & desenvolvimento , Rubiaceae/crescimento & desenvolvimento , Rubiaceae/fisiologia , Plântula/crescimento & desenvolvimento , Fotossíntese/fisiologia , Brasil
2.
Nat Prod Res ; : 1-6, 2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37367484

RESUMO

In the present study, we have evaluated the cytotoxic activity of 282 extracts from 72 native plant species of the Brazilian Atlantic Forest biome. As a result, Casearia arborea and Sorocea hilarii leaves extracts showed cytotoxic activity against three tumour cell lines tested (B16F10, SW480 and Jurkat). After bioassay-guided fractionation, the bioactive fractions were submitted to the dereplication study via High-performance Liquid Chromatography, connected to High-resolution Mass Spectrometry (HPLC-ESI-QTOF/MS) analysis, combined with a Global Natural Products Social Molecular Networking (GNPS) tool. A combination of bioactivity-guided and dereplication approaches resulted in the putative annotation of 27 clerodane diterpenes and 9 flavonoids as main compounds present in the cytotoxic fractions of C. arborea. Regarding the active fraction of S. hilarii, 10 megastigmans, 17 spirostane steroids derivatives and 2 lignans were putatively identified. In conclusion, Casearia arborea and Sorocea hilarii are potential sources of antitumor compounds.

3.
Braz J Med Biol Res ; 55: e12116, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35976270

RESUMO

Cisplatin is an effective antineoplastic agent, but its use is limited by its nephrotoxicity caused by the oxidative stress in tubular epithelium of nephrons. On the other hand, regular exercise provides beneficial adaptations in different tissues and organs. As with many drugs, dosing is extremely important to get the beneficial effects of exercise. Thus, we aimed to investigate the influence of exercise intensity and frequency on cisplatin-induced (20 mg/kg) renal damage in mice. Forty male Swiss mice were divided into five experimental groups (n=8 per group): 1) sedentary; 2) low-intensity forced swimming, three times per week; 3) high-intensity forced swimming, three times per week; 4) low-intensity forced swimming, five times per week; and 5) high-intensity forced swimming, five times per week. Body composition, renal structure, functional indicators (plasma urea), lipid peroxidation, antioxidant enzyme activity, expression of genes related to antioxidant defense, and inflammatory and apoptotic pathways were evaluated. Comparisons considered exercise intensity and frequency. High lipid peroxidation was observed in the sedentary group compared with trained mice, regardless of exercise intensity and frequency. Groups that trained three times per week showed more benefits, as reduced tubular necrosis, plasma urea, expression of CASP3 and Rela (NFkB subunit-p65) genes, and increased total glutathione peroxidase activity. No significant difference in Nfe2l2 (Nrf2) gene expression was observed between groups. Eight weeks of regular exercise training promoted nephroprotection against cisplatin-mediated oxidative injury. Exercise frequency was critical for nephroprotection.


Assuntos
Antioxidantes , Cisplatino , Animais , Antioxidantes/farmacologia , Cisplatino/toxicidade , Peroxidação de Lipídeos , Masculino , Camundongos , Estresse Oxidativo , Natação , Ureia
4.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;55: e12116, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1394127

RESUMO

Cisplatin is an effective antineoplastic agent, but its use is limited by its nephrotoxicity caused by the oxidative stress in tubular epithelium of nephrons. On the other hand, regular exercise provides beneficial adaptations in different tissues and organs. As with many drugs, dosing is extremely important to get the beneficial effects of exercise. Thus, we aimed to investigate the influence of exercise intensity and frequency on cisplatin-induced (20 mg/kg) renal damage in mice. Forty male Swiss mice were divided into five experimental groups (n=8 per group): 1) sedentary; 2) low-intensity forced swimming, three times per week; 3) high-intensity forced swimming, three times per week; 4) low-intensity forced swimming, five times per week; and 5) high-intensity forced swimming, five times per week. Body composition, renal structure, functional indicators (plasma urea), lipid peroxidation, antioxidant enzyme activity, expression of genes related to antioxidant defense, and inflammatory and apoptotic pathways were evaluated. Comparisons considered exercise intensity and frequency. High lipid peroxidation was observed in the sedentary group compared with trained mice, regardless of exercise intensity and frequency. Groups that trained three times per week showed more benefits, as reduced tubular necrosis, plasma urea, expression of CASP3 and Rela (NFkB subunit-p65) genes, and increased total glutathione peroxidase activity. No significant difference in Nfe2l2 (Nrf2) gene expression was observed between groups. Eight weeks of regular exercise training promoted nephroprotection against cisplatin-mediated oxidative injury. Exercise frequency was critical for nephroprotection.

5.
Braz J Med Biol Res ; 52(4): e8154, 2019 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-30970084

RESUMO

Elite judo demands high levels of physical and psychological skills. The brain-derived neurotrophic factor (BDNF) may be of particular interest in sports medicine for its ability to promote neuroplasticity. We investigated the plasma BDNF before and after a judo training session (Randori) and the maximal incremental ramp test (MIRT) in athletes from the Brazilian national judo team and compared the results between both exercise stimuli and sexes. Fifty-six elite judo athletes were recruited who performed each task on a separated day. Anthropometric, physiological, athletic parameters, and plasma BDNF levels were measured before and after the tasks (Randori and MIRT). The groups presented similar anthropometric and physiological characteristics at baseline for the two tasks. All athletes reached maximal performance for the tasks. Plasma levels of BDNF increased significantly after Randori and MIRT for all subjects, both men and women. When comparing both exercise stimuli, a greater increase in BDNF was observed after Randori. There was no significant difference in the delta BDNF between sexes. Our findings indicate that training specificity of sport gestures influenced the increase of blood BDNF levels.


Assuntos
Desempenho Atlético/fisiologia , Fator Neurotrófico Derivado do Encéfalo/sangue , Artes Marciais/fisiologia , Resistência Física/fisiologia , Adulto , Feminino , Humanos , Masculino
6.
Plant Biol (Stuttg) ; 21(5): 844-853, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30927480

RESUMO

Environmental cadmium (Cd) sources have increased in mangrove sediments in recent decades, inducing cellular damage to many plants. Avicennia schaueriana is abundant in mangrove sites and has been subject to Cd contamination. The possible effects of Cd toxicity and the structural and physiological disturbances to this plant were studied. Can this plant express early cellular tolerance mechanisms to such metal contamination? Seedlings of A. schaueriana were collected from sites of their natural occurrence, placed in plastic pots containing nutrient solution for 60 days, and subsequently exposed to increasing Cd concentrations for 5 days under experimental conditions. The anatomical, ultrastructural and physiological changes induced by Cd were analysed. Cd accumulated mainly in the root system and in pneumatophores, stems and leaves, induced differential accumulation of mineral nutrients, but did not induce necrosis or changes in leaf anatomy. However, there was a decrease in starch grains and an increase in deposited electron-dense material in the cortex and vascular bundles. Cd induced both increases in calcium (Ca) content in shoots and Ca oxalate crystal precipitation in leaf mesophyll and was detected in crystals and in the secretion of salt glands. Our observations and experimental results provide evidence of Cd tolerance in A. schaueriana. As a new feature, despite the clear cellular physiological disorders, this plant is able to eliminate Cd through leaf salt glands and immobilise it in Ca crystals, representing fast mechanisms for Cd exclusion and complexation in leaves in heavy metal coastal polluted marine ecosystems.


Assuntos
Avicennia/efeitos dos fármacos , Cádmio/toxicidade , Folhas de Planta/metabolismo , Avicennia/metabolismo , Avicennia/ultraestrutura , Cádmio/metabolismo , Cálcio/metabolismo , Microscopia Eletrônica de Transmissão , Raízes de Plantas/metabolismo , Caules de Planta/metabolismo , Plântula/efeitos dos fármacos , Plântula/metabolismo , Plântula/ultraestrutura
7.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;52(4): e8154, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1001509

RESUMO

Elite judo demands high levels of physical and psychological skills. The brain-derived neurotrophic factor (BDNF) may be of particular interest in sports medicine for its ability to promote neuroplasticity. We investigated the plasma BDNF before and after a judo training session (Randori) and the maximal incremental ramp test (MIRT) in athletes from the Brazilian national judo team and compared the results between both exercise stimuli and sexes. Fifty-six elite judo athletes were recruited who performed each task on a separated day. Anthropometric, physiological, athletic parameters, and plasma BDNF levels were measured before and after the tasks (Randori and MIRT). The groups presented similar anthropometric and physiological characteristics at baseline for the two tasks. All athletes reached maximal performance for the tasks. Plasma levels of BDNF increased significantly after Randori and MIRT for all subjects, both men and women. When comparing both exercise stimuli, a greater increase in BDNF was observed after Randori. There was no significant difference in the delta BDNF between sexes. Our findings indicate that training specificity of sport gestures influenced the increase of blood BDNF levels.


Assuntos
Humanos , Masculino , Feminino , Adulto , Resistência Física/fisiologia , Artes Marciais/fisiologia , Fator Neurotrófico Derivado do Encéfalo/sangue , Desempenho Atlético/fisiologia
8.
Genet Mol Res ; 15(1)2016 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-26910005

RESUMO

The recessive lethal character Luteus-Pa is found in cacao (Theobroma cacao) genotypes of the Parinari series (Pa) and is characterized by expression of leaf chlorosis and seedling death. Several genotypes of the Pa series are bearers of the gene responsible for the expression of the Luteus-Pa character, which can be used as a tool for determining relationships between genotypes of this group. To evaluate this phenomenon, we analyzed the differential expression of genes between mutant seedlings and wild-type hybrid Pa 30 x 169 seedlings, with the aim of elucidating the possible lethal mechanisms of the homozygous recessive character Luteus-Pa. Plant material was harvested from leaves of wild and mutant seedlings at different periods to construct a subtractive library and perform quantitative analysis using real-time PCR. The 649 sequences obtained from the subtractive library had an average length of 500 bp, forming 409 contigs. The probable proteins encoded were grouped into 10 functional categories. Data from ESTs identified genes associated with Rubisco, peroxidases, and other proteins and enzymes related to carbon assimilation, respiration, and photosystem 2. Mutant seedlings were characterized by synthesizing defective PsbO and PsbA proteins, which were overexpressed from 15 to 20 days after seedling emergence.


Assuntos
Cacau/genética , Cacau/metabolismo , Regulação da Expressão Gênica de Plantas , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Plântula/metabolismo , Genótipo , Folhas de Planta/genética , Proteínas de Plantas/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Plântula/genética
9.
Genet Mol Res ; 13(3): 5036-47, 2014 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-25062492

RESUMO

Theobroma cacao is a woody and recalcitrant plant with a very high level of interfering compounds. Standard protocols for protein extraction were proposed for various types of samples, but the presence of interfering compounds in many samples prevented the isolation of proteins suitable for two-dimensional gel electrophoresis (2-DE). An efficient method to extract root proteins for 2-DE was established to overcome these problems. The main features of this protocol are: i) precipitation with trichloroacetic acid/acetone overnight to prepare the acetone dry powder (ADP), ii) several additional steps of sonication in the ADP preparation and extractions with dense sodium dodecyl sulfate and phenol, and iii) adding two stages of phenol extractions. Proteins were extracted from roots using this new protocol (Method B) and a protocol described in the literature for T. cacao leaves and meristems (Method A). Using these methods, we obtained a protein yield of about 0.7 and 2.5 mg per 1.0 g lyophilized root, and a total of 60 and 400 spots could be separated, respectively. Through Method B, it was possible to isolate high-quality protein and a high yield of roots from T. cacao for high-quality 2-DE gels. To demonstrate the quality of the extracted proteins from roots of T. cacao using Method B, several protein spots were cut from the 2-DE gels, analyzed by tandem mass spectrometry, and identified. Method B was further tested on Citrus roots, with a protein yield of about 2.7 mg per 1.0 g lyophilized root and 800 detected spots.


Assuntos
Cacau/química , Extração Líquido-Líquido/métodos , Proteínas de Plantas/isolamento & purificação , Raízes de Plantas/química , Acetona , Eletroforese em Gel Bidimensional , Espectrometria de Massas , Meristema/química , Fenol , Folhas de Planta/química , Proteínas de Plantas/química , Dodecilsulfato de Sódio , Solventes , Sonicação , Ácido Tricloroacético
10.
Oxid Med Cell Longev ; 2013: 194192, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23577220

RESUMO

2-[(2,6-Dichlorobenzylidene)amino]-5,6-dihydro-4H-cyclopenta[b]thiophene-3-carbonitrile, 5TIO1, is a new 2-aminothiophene derivative with promising pharmacological activities. The aim of this study was to evaluate its antioxidant activity in different areas of mice central nervous system. Male Swiss adult mice were intraperitoneally treated with Tween 80 dissolved in 0.9% saline (control group) and 5TIO1 (0.1, 1, and 10 mg kg(-1)). Brain homogenates-hippocampus, striatum, frontal cortex, and cerebellum-were obtained after 24 h of observation. Superoxide dismutase and catalase activities, lipid peroxidation and nitrite content were measured using spectrophotometrical methods. To clarify the 5TIO1's mechanism on oxidative stress, western blot analysis of superoxide dismutase and catalase was also performed. 5TIO1 decreased lipid peroxidation and nitrite content in all brain areas and increased the antioxidant enzymatic activities, specially, in cerebellum. The data of Western blot analysis did not demonstrate evidence of the upregulation of these enzymes after the administration of this compound. Our findings strongly support that 5TIO1 can protect the brain against neuronal damages regularly observed during neuropathologies.


Assuntos
Antioxidantes/farmacologia , Encéfalo/metabolismo , Estresse Oxidativo , Bases de Schiff/farmacologia , Tiofenos/farmacologia , Animais , Antioxidantes/química , Encéfalo/efeitos dos fármacos , Catalase/metabolismo , Cerebelo/enzimologia , Cerebelo/metabolismo , Corpo Estriado/enzimologia , Corpo Estriado/metabolismo , Lobo Frontal/enzimologia , Lobo Frontal/metabolismo , Hipocampo/enzimologia , Hipocampo/metabolismo , Injeções Intraperitoneais , Peroxidação de Lipídeos , Masculino , Camundongos , Nitritos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Bases de Schiff/química , Superóxido Dismutase/metabolismo , Tiofenos/química
11.
Genet Mol Res ; 11(3): 2694-707, 2012 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-22843071

RESUMO

Sibipiruna (Caesalpinia peltophoroides Benth) is a tree of the Brazilian Atlantic Forest. It is a flowering ornamental tree widely planted throughout Brazil and indicated for restoration of degraded areas. We examined protein profile changes in leaves of seedlings of C. peltophoroides grown in nutrient solution under greenhouse conditions, after exposure to cadmium (Cd; 32 mg/L). A two-dimensional gel was used to analyze proteins expressed in response to stress 24 and 72 h after initiation of treatment with Cd. Various protein bands were identified that were related to stress response and/or metabolic adjustments, including proteins involved with resistance to stress, including detoxification, degradation, antioxidant, transport, signal transduction, photosynthesis, electron transport, biosynthesis reactions, and transcription regulation. After 24 h of Cd exposure, the genes of most of these proteins were upregulated. These putative proteins were associated with resistance to stress, including heat shock proteins, heat stress transcriptional factor and other transcriptional factors, aquaporins, glutathione transferase and choline monooxygenase. Most of the putative proteins observed after 72 h of exposure to Cd were downregulated. They were mainly photosynthetic process proteins, such as NAD(P)H-quinone oxidoreductase, photosystem I assembly, and photosystem II CP47 chlorophyll apoprotein. There were also proteins involved with degradation, biosynthesis and antioxidant activity, such as ATP-dependent Clp protease, methylthioribose-1-phosphate and glutathione peroxidase 2. Based on preliminary proteomic analysis, we conclude that proteins related to photosynthetic activity are inhibited, decreasing plant performance under stress conditions and that several proteins related to defense mechanisms are activated, inducing the plant defense response.


Assuntos
Cádmio/toxicidade , Caesalpinia/efeitos dos fármacos , Caesalpinia/metabolismo , Proteínas de Plantas/metabolismo , Proteoma/metabolismo , Proteômica , Plântula/metabolismo , Eletroforese em Gel Bidimensional , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Plântula/efeitos dos fármacos
12.
Genet Mol Res ; 10(4): 2457-71, 2011 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-22009858

RESUMO

We estimated genetic parameters through multivariate analysis of two species of Passiflora and their hybrids, considered of ornamental potential, based on the morphological characteristics: flower diameter, corona diameter, corona filament size, flower peduncle length, petal length and width, sepal length and width, internode length, stem diameter, leaf length, leaf width (mm), and leaf area (cm(2)). Five specimens of Passiflora sublanceolata [ex P. palmeri var. sublanceolata], five of P. foetida var. foetida and 20 F(1) hybrids between the two were evaluated. A randomized block design with four replications was used. The data were submitted to variance analysis and multivariate procedures, principal components analysis and unweighted pair group method with arithmetic mean grouping. We found significant differences between genotypes for all these morphological parameters. The hybrid plants had the highest variability, making them the most indicated for future improvement programs. The various multivariate techniques gave similar results, allowing separation of the plants into three distinct groups, these being the two paternal species and the hybrids. The hybrids were closer to the male genitors, revealing a paternal effect on the inheritance of vegetative and floral characters. Based on estimates of genetic parameters, the floral characteristics are the most indicated for the selection of plants for ornamental purposes, since these characteristics displayed greatest variability, a variation index of more than one, and high genotypic determination coefficients.


Assuntos
Quimera/genética , Flores/genética , Genótipo , Passiflora/genética , Folhas de Planta/genética , Caules de Planta/genética , Análise Multivariada , Especificidade da Espécie
13.
Pharmazie ; 66(8): 623-7, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21901988

RESUMO

We examined the sedative, anxiolytic and antidepressant effects of essential oil (EO) of leaves from Citrus limon, which has been used as one of the most popular compounds in Brazilian traditional herbal medicine. The effects of EO were demonstrated by open-field, elevated-plus-maze, rota rod, pentobarbital-induced sleeping time, and forced swimming tests in mice. In the open-field test, EO at the doses of 50, 100 and 150 mg/kg, after oral administration, significantly decreased the number of crossings, grooming, and rearing. In the elevated-plus-maze (EPM) test, EO increased the time of permanence and the number of entrances in the open arms. On the contrary, the time of permanence and the number of entrances in the closed arms were decreased. In the rota rod test, EO did not alter motor coordination and, thus, was devoid of effects, as related to controls. In the pentobarbital-induced sleeping time test, EO at the same doses significantly increased the animals sleeping time duration. Since EO, at the doses of 50, 100 and 150 mg/kg, did not show a sedative effect in the open field test, these three doses were used in the forced swimming test, producing a decrease in the immobility time, similarly to that of imipramine (positive control). However, the antidepressant effects of EO were not altered by the previous administration of paroxetine. In addition, effects of EO in the forced swimming test were totally blocked by reserpine pretreatment. In conclusion, the present work evidenced sedative and anxiolytic effects of EO that might involve an action on benzodiazepine-type receptors, and also an antidepressant effect where noradrenergic and serotoninergic mechanisms will probably play a role.


Assuntos
Ansiolíticos , Antidepressivos , Citrus/química , Hipnóticos e Sedativos , Óleos Voláteis/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Temperatura Corporal/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Masculino , Camundongos , Atividade Motora/efeitos dos fármacos , Pentobarbital/farmacologia , Equilíbrio Postural/efeitos dos fármacos , Sono/efeitos dos fármacos , Natação/psicologia
14.
Genet Mol Res ; 9(3): 1775-84, 2010 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-20830669

RESUMO

The lethal gene 'Luteus-Pa' is found in cacao genotypes (Theobroma cacao) of the Parinari (Pa) series, from Peru. Seedlings affected by this gene have yellowing leaves and subsequently die. We mapped this gene based on microsatellite markers and RAPDs, in order to elucidate the inheritance of 'Luteus-Pa' and investigate possible lethal mechanisms. DNA samples of genitors were amplified with 87 SSR and 64 RAPD primers. The SSR primers amplified 65 RAPD primers, giving 179 polymorphic bands. After screening with SSR and RAPD markers, we selected 20 SSR primers, two SSR primers with ESTs and 22 RAPD primers that were polymorphic for genitors Pa 30 and Pa 169. Only two of the 22 RAPD primers and three of the 20 SSR primers were informative and polymorphic in the analysis of the bulk samples of progenies. Among these, primer RAPD E11 produced a band linked to the lethal gene (38.5 cM); none of the SSRs were associated with 'Luteus-Pa'.


Assuntos
Malvaceae/genética , Plântula/genética , DNA de Plantas/genética , Genótipo , Malvaceae/crescimento & desenvolvimento , Repetições de Microssatélites/genética , Reação em Cadeia da Polimerase , Técnica de Amplificação ao Acaso de DNA Polimórfico , Plântula/crescimento & desenvolvimento
15.
São Paulo; São Paulo (Cidade). Secretaria da Saúde. Coordenação de Vigilância em Saúde. Gerência do Centro de Controle de Zoonoses; 2010.
Não convencional em Português | LILACS, Coleciona SUS, COVISA-Producao, Sec. Munic. Saúde SP, Sec. Munic. Saúde SP | ID: biblio-937004
17.
18.
Genet Mol Res ; 8(3): 976-89, 2009 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-19731198

RESUMO

We examined leaf CO(2) assimilation and how it varied among species within the orchid genus Cattleya. Measurements of CO(2) assimilation and maximum quantum yield of PS II (Fv/Fm) were made for mature leaves of nine species using a portable system for photosynthesis measurement and a portable fluorometer. Leaf area was measured with an area meter, and the specific leaf mass was determined. DNA of nine Cattleya species and two species of Hadrolaelia was extracted using the CTAB protocol. Each sample was amplified and sequenced using primers for the trnL gene. The phylogenetic analyses, using neighbor-joining and maximum parsimony methods, retrieved a group that included Cattleya and Hadrolaelia species, in which the unifoliate species were separated from the bifoliates. The topologies of the two cladograms showed some similarities. However, C. guttata (bifoliate) was placed in the unifoliate clade in the neighbor-joining tree, while C. warneri (unifoliate) was not placed in this clade in the maximum parsimony tree. Most Cattleya species keep the leaf stomata closed from 6 am to 4 pm. We suggest that C. elongata, C. tigrina and C. tenuis have C(3)-crassulacean acid metabolism since they open their stomata around 12 am. The Fv/Fm values remained relatively constant during the measurements of CO(2) assimilation. The same was observed for the specific leaf mass values, although great variations were found in the leaf area values. When the species were grouped using molecular data in the neighbor-joining analysis, no relation was observed with CO(2) assimilation.


Assuntos
Carbono/metabolismo , Orchidaceae/genética , Orchidaceae/metabolismo , Filogenia , Folhas de Planta/genética , Folhas de Planta/metabolismo , Biomassa , Dióxido de Carbono/metabolismo , Fotossíntese
20.
Genet Mol Res ; 7(4): 1282-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19065763

RESUMO

Many cell functions are redundantly executed in cells, and the experimental approaches that analyze the group of proteins, whose expression is modified in a specific functional condition, enable the identification of the group of proteins that are expressed under stress conditions. The objective of the present study was the evaluation of the genetic expression induced by cadmium (Cd) in Genipa americana L. (Rubiaceae) plants cultivated in nutritive solution, in order to help further studies concerning its use as a plant phytoremediator of such a metallic element. Plants were exposed to increasing concentrations of Cd (0.5, 1, 2, 4, 8, and 16 mg/L), together with the control, in nutritive solution. After the application of the treatments, root tips were harvested for the construction of a cDNA library. Of the 165 expressed sequence tags (ESTs) generated with the construction of the cDNA library, 81 showed homology to genes deposited in the NCBI database, 67 did not show similarity to any available gene, and 17 ESTs demonstrated homology with unknown genes. Of the most abundant cDNAs, 16 ESTs were similar to sequences of metallothionein genes. The analysis of ESTs, obtained from the root of G. americana through the construction of a cDNA library, allowed the identification of genes probably associated with proteins and enzymes related to the defense mechanisms of plants when they undergo biotic and abiotic stresses.


Assuntos
Cádmio/farmacologia , Etiquetas de Sequências Expressas , Regulação da Expressão Gênica de Plantas , Raízes de Plantas/genética , Rubiaceae/genética , Biodegradação Ambiental , DNA Complementar/genética , Alimentos , Biblioteca Gênica
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