RESUMO
Arguably, the nitrogen (N) is an important and essential component for plant growth and development. Among the sources of N available, the ammonium is a major inorganic nitrogen source for plants is mobilized by ammonium transporter (AMT). In this study, data mining revealed that the Ananas comosus L. genome was identified eight genes of the AMT family. Based on this information, we conducted a comprehensive analysis using some bioinformatics tools in order to individually characterize the identified genes. The comprehensive analysis of AMT will provide an important foundation for further investigation of the regulatory mechanisms of AcoAMTs in A. comosus L.(AU)
Indiscutivelmente, o nitrogênio (N) é um componente importante e essencial para o crescimento e desenvolvimento das plantas. Dentre as fontes de N disponíveis, o amônio é a principal fonte de nitrogênio inorgânico para as plantas, sendo mobilizado pelo transportador de amônio (AMT). Neste estudo, a mineração de dados revelou que no genoma de Ananas comosus L. foram identificados oito genes da família AMT. Com base nessas informações, realizamos uma análise abrangente usando algumas ferramentas de bionformática com a finalidade de caracterizar individualmente os genes identificados. A análise abrangente do AMT fornecerá uma base importante para uma investigação mais aprofundada dos mecanismos regulatórios de AcoAMTs em A. comosus L.(AU)
Assuntos
Ananas/genética , Mineração de Dados , NitrogênioRESUMO
Arguably, the nitrogen (N) is an important and essential component for plant growth and development. Among the sources of N available, the ammonium is a major inorganic nitrogen source for plants is mobilized by ammonium transporter (AMT). In this study, data mining revealed that the Ananas comosus L. genome was identified eight genes of the AMT family. Based on this information, we conducted a comprehensive analysis using some bioinformatics tools in order to individually characterize the identified genes. The comprehensive analysis of AMT will provide an important foundation for further investigation of the regulatory mechanisms of AcoAMTs in A. comosus L.
Indiscutivelmente, o nitrogênio (N) é um componente importante e essencial para o crescimento e desenvolvimento das plantas. Dentre as fontes de N disponíveis, o amônio é a principal fonte de nitrogênio inorgânico para as plantas, sendo mobilizado pelo transportador de amônio (AMT). Neste estudo, a mineração de dados revelou que no genoma de Ananas comosus L. foram identificados oito genes da família AMT. Com base nessas informações, realizamos uma análise abrangente usando algumas ferramentas de bionformática com a finalidade de caracterizar individualmente os genes identificados. A análise abrangente do AMT fornecerá uma base importante para uma investigação mais aprofundada dos mecanismos regulatórios de AcoAMTs em A. comosus L.
Assuntos
Ananas/genética , Mineração de Dados , NitrogênioRESUMO
Due to the increasing search for renewable resources, plant fibers have become an alternative when creating new products. Studies demonstrate the potential use of pineapple fibers in composites. The objective of this work was to evaluate the genetic diversity and verify any association between ISSR (Inter Simple Sequence Repeats) bands and quality of pineapple fibers for use in cements in the civil construction. The study analyzed the genetic variability of 11 pineapple genotypes, as well as the possible association of 131 bands from 16 ISSR markers with fiber quality characteristics. Eleven bands were selected based on their high correlations (0.64578* to 0.72457*) with three fiber quality variables. Of these, two bands were purified, sequenced, and blasted against sequences in GenBank at NCBI. These markers can be used in marker assisted selection to genetically improve the quality of pineapple fiber. Bands that returned no hits in the NCBI BLAST search can be deposited as new sequences in the GenBank. Therefore, the SCAR markers, once validated, can be useful in pineapple genetic breeding programs worldwide by using molecular marker assisted selection for fiber resistance, which could subsidize the development of more promising genotypes for industrial use and contribute to the sustainability of this new production sector.
Assuntos
Ananas/genética , Marcadores Genéticos , Repetições de Microssatélites/genética , Cruzamento , Variação Genética , Genótipo , Filogenia , Polimorfismo Genético , Estatísticas não ParamétricasRESUMO
Natural flowering can cause serious scheduling problems in the pineapple (Ananas comosus) industry and increase harvest costs. Pineapple flowering is thought to be triggered by increased ethylene levels and artificial forcing of pineapple flowering is a common practice to promote flowering synchronisation. However, little is known about the early hormonal and molecular changes of pineapple flowering induction and development. Here, we aimed to analyse the molecular, hormonal, and histological changes during artificial pineapple flowering by Ethrel®48 treatment. Histological analyses of the shoot apical meristem, leaf gibberellic acid (GA3), and ethylene quantification were carried out during the first 72h after Ethrel®48 treatment. Expression profiles from ethylene biosynthesis (AcACS2 and AcACO1), gibberellin metabolism (AcGA2-ox1 and AcDELLA1), and flower development (FT-like gene (AcFT), LFY-like gene (AcLFY), and a PISTILLATA-like gene (AcPI)) genes were analysed during the first 24h after Ethrel®48 treatment. Differentiation processes of the shoot apical meristem into flower buds were already present in the first 72h after Ethrel®48 treatment. Ethrel®48 lead to a reduction in GA3 levels, probably triggered by elevated ethylene levels and the positive regulation AcGA2-ox1. AcLFY activation upon Ethrel®48 may also have contributed to the reduction of GA3 levels and, along with the up-regulation of AcPI, are probably associated with the flower induction activation. AcFT and AcDELLA1 do not seem to be regulated by GA3 and ethylene. Decreased GA3 and increased ethylene levels suggest an accumulation of AcDELLA1, which may display an important role in pineapple flowering induction. Thus, this study shows that molecular, hormonal, and histological changes are present right after Ethrel®48 treatment, providing new insights into how pineapple flowering occurs under natural conditions.
Assuntos
Ananas/anatomia & histologia , Ananas/citologia , Flores/fisiologia , Reguladores de Crescimento de Plantas/metabolismo , Sequência de Aminoácidos , Ananas/genética , Etilenos/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Giberelinas/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMO
The genetic relationships among 27 pineapple [Ananas comosus (L.) Merr.] cultivars and lines were examined using 16 simple sequence repeat (SSR) markers. The number of alleles per locus of the SSR markers ranged from 2 to 6 (average 3.19), for a total of 51 alleles. Similarity coefficients were calculated on the basis of 51 amplified bands. A dendrogram was created according to the 16 SSR markers by the unweighted pair-group method. The banding patterns obtained from the SSR primers allowed most of the cultivars and lines to be distinguished, with the exception of vegetative clones. According to the dendrogram, the 27 pineapple cultivars and lines were clustered into three main clusters and four individual clusters. As expected, the dendrogram showed that derived cultivars and lines are closely related to their parental cultivars; the genetic relationships between pineapple cultivars agree with the genealogy of their breeding history. In addition, the analysis showed that there is no obvious correlation between SSR markers and morphological characters. In conclusion, SSR analysis is an efficient method for pineapple cultivar identification and can offer valuable informative characters to identify pineapple cultivars in Taiwan.
Assuntos
Ananas/genética , Repetições de Microssatélites/genética , Alelos , Ananas/classificação , Cruzamento , Análise por Conglomerados , Marcadores Genéticos/genética , Variação Genética , Especificidade da Espécie , TaiwanRESUMO
Blackheart is a physiological disorder induced by postharvest chilling storage during pineapple fruit export shipping. The aim of this study was to check the involvement of bromelain, the cysteine protease protein family abundantly present in pineapple fruits, and AcCYS1, an endogenous inhibitor of bromelain, in the development of blackheart. For this we checked the response to postharvest chilling treatment of two pineapple varieties (MD2 and Smooth Cayenne) differing in their resistance to blackheart. Quantitative RT-PCR analyses showed that postharvest chilling treatment induced a down-regulation of bromelain transcript accumulation in both varieties with the most dramatic drop in the resistant variety. Regarding AcCYS1 transcript accumulation, the varieties showed opposite trends with an up-regulation in the case of the resistant variety and a down-regulation in the susceptible one. Taken together our results suggest that the control of bromelain and AcCYS1 expression levels directly correlates to the resistance to blackheart development in pineapple fruits.
Assuntos
Ananas/fisiologia , Bromelaínas/genética , Cistatinas/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Ananas/genética , Bromelaínas/metabolismo , Temperatura Baixa , Cistatinas/metabolismo , Frutas/genética , Frutas/fisiologia , Dados de Sequência Molecular , Proteínas de Plantas/metabolismo , Reação em Cadeia da Polimerase , Análise de Sequência de DNARESUMO
The events involved in the structural interaction between the diazotrophic endophytic bacterium Herbaspirillum seropedicae, strain RAM10, labeled with green fluorescent protein, and pineapple plantlets 'Vitória' were evaluated by means of bright-field and fluorescence microscopy, combined with scanning electron microscopy for 28 days after inoculation. After 6 hours of inoculation, H. seropedicae was already adhered to the roots, colonizing mainly root hair surface and bases, followed by epidermal cell wall junctions. Bacteria adherence in the initial periods occurred mainly in the form of solitary cells and small aggregates with pleomorphic cells. Bacteria infection of root tissue occurred through the cavities caused by the disruption of epidermal cells during the emergence of lateral roots and the endophytic establishment by the colonization of intercellular spaces of the cortical parenchyma. Moreover, within 1 day after inoculation the bacteria were colonizing the shoots. In this region, the preferred sites of epiphytic colonization were epidermal cell wall junctions, peltate scutiform trichomes and non-glandular trichomes. Subsequently, the bacteria occupied the outer periclinal walls of epidermal cells and stomata. The penetration into the shoot occurred passively through stoma aperture followed by the endophytic establishment on the substomatal chambers and spread to the intercellular spaces of spongy chlorenchyma. After 21 days of inoculation, bacterial biofilm were seen at the root hair base and on epidermal cell wall surface of root and leaf, also confirming the epiphytic nature of H. seropedicae.
Assuntos
Ananas/crescimento & desenvolvimento , Ananas/genética , Biofilmes , Parede Celular , Fixação de Nitrogênio/genética , Herbaspirillum/crescimento & desenvolvimento , Herbaspirillum/isolamento & purificação , Técnicas In Vitro , Microscopia Eletrônica , Proteínas de Fluorescência Verde/análise , Técnicas Genéticas , Métodos , Microscopia de Fluorescência , PlantasRESUMO
Pineapple internal browning (IB) is a chilling injury that produces enzymatic browning associated with flesh translucency. Pineapple biodiversity allowed the investigation of how polyphenol oxidase (PPO) and peroxidase (POD) activities with their different isoforms are involved in the IB mechanism. Fruits of four varieties that expressed IB symptoms differently, Smooth Cayenne (SCay) and the hybrids MD2, Flhoran 41 (Flh 41), and Flhoran 53 (Flh 53), were stressed by cold. The susceptible varieties showed classical brown spots but different patterns of IB, whereas MD2 and controls showed no IB. Enzymatic activities were measured on fruit protein extracts and PPO and POD isoforms separated on mini-gels (PhastSystem). Only PPO activity was significantly enhanced in the presence of IB. Up to six PPO isoforms were identified in the susceptible varieties. PPO was barely detectable in the nonsusceptible variety MD2 and in controls. The number of PPO isoforms and the total PPO activity after chilling are varietal characteristics.
Assuntos
Ananas/enzimologia , Catecol Oxidase/genética , Regulação Enzimológica da Expressão Gênica , Peroxidase/genética , Proteínas de Plantas/genética , Ananas/genética , Catecol Oxidase/metabolismo , Temperatura Baixa , Frutas/enzimologia , Frutas/genética , Peroxidase/metabolismo , Proteínas de Plantas/metabolismoRESUMO
Nitrate reductase (NR, EC 1.6.6.1) activity in higher plants is regulated by a variety of environmental factors and oscillates with a characteristic diurnal rhythm. In this study, we have demonstrated that the diurnal cycle of NR expression and activity in pineapple (Ananas comosus, cv. Smooth Cayenne) can be strongly modified by changes in the day/night temperature regime. Plants grown under constant temperature (28 degrees C light/dark) showed a marked increase in the shoot NR activity (NRA) during the first half of the light period, whereas under thermoperiodic conditions (28 degrees C light/15 degrees C dark) significant elevations in the NRA were detected only in the root tissues at night. Under both conditions, increases in NR transcript levels occurred synchronically about 4 h prior to the corresponding elevation of the NRA. Diurnal analysis of endogenous cytokinins indicated that transitory increases in the levels of zeatin, zeatin riboside and isopentenyladenine riboside coincided with the accumulation of NR transcripts and preceded the rise of NRA in the shoot during the day and in the root at night, suggesting these hormones as mediators of the temperature-induced modifications of the NR cycle. Moreover, these cytokinins also induced NRA in pineapple when applied exogenously. Altogether, these results provide evidence that thermoperiodism can modify the diurnal cycle of NR expression and activity in pineapple both temporally and spatially, possibly by modulating the day/night changes in the cytokinin levels. A potential relationship between the day/night NR cycle and the photosynthetic pathway performed by the pineapple plants (C(3) or CAM) is also discussed.
Assuntos
Ananas/enzimologia , Ritmo Circadiano , Citocininas/metabolismo , Nitrato Redutase/metabolismo , Proteínas de Plantas/metabolismo , Ananas/genética , DNA de Plantas/genética , Regulação da Expressão Gênica de Plantas , Nitrato Redutase/genética , Proteínas de Plantas/genética , Análise de Sequência de DNA , TemperaturaRESUMO
The objective of the present study was to evaluate the genetic variability in micropropagated plantlets of ornamental pineapple, after the fourth period of subculture. The basal culture medium consisted of MS salts, vitamins, 3% sucrose, liquid formulation, supplemented with 6-benzylaminopurine (BAP) at concentrations of 0.125, 0.25, 0.5, 1.0, and 2.0 mg/L. The addition of BAP influenced the occurrence of genetic variation revealed using random amplified polymorphic DNA (RAPD) markers. Of a total of 520 primers tested, 44 were selected and amplified; 402 monomorphic bands (97.2%) and 18 polymorphic bands (2.8%) resulted among regenerated plantlets. The polymorphic fragments were produced by 12 primers (OPA-01, OPA-20, OPB-01, OPB-19, OPC-19, OPF-13, OPL-17, OPM-13, OPP-16, OPT-07, OPV-19, and OPX-03). Among the primers that identified polymorphism, OPA-01, OPA-20, OPB-19, OPC-19, OPL-17, OPP-16, and OPX-3 each showed, one polymorphic band and OPF-13 amplified a maximum of three bands. In this study, the RAPD technique was effective in showing the occurrence of somaclonal variations that occur during the micropropagation process of ornamental pineapple cultivation in BAP-supplemented medium, and it is possible to detect the presence of genetic variation in early stages of plant development.
Assuntos
Ananas/genética , Variação Genética , Técnica de Amplificação ao Acaso de DNA Polimórfico/métodos , Primers do DNA/genética , DNA de Plantas/genética , DNA de Plantas/metabolismo , Marcadores Genéticos/genéticaRESUMO
A procedure for pineapple [Ananas comosus (L.) Merr.] genetic transformation is described, which involves temporary immersion bioreactors (TIB) for selection of transgenic plants. Success in the production of transgenic pineapple plants combines tissue culture factors. Firstly, the use of regenerable pineapple callus as starting material for transformation whose cells shown to be competent for Agrobacterium infection. Secondly, the used of filtered callus, resulting in homogeneously sized clusters, thereby increasing the contact between the cell surfaces and A. tumefaciens and releasing phenolic compounds which induce Agrobacterium virulence. Thirdly, regeneration of primary plants without selection pressure, that allowing a massive production of putative transgenic pineapples. Finally, we support that TIB technology is a powerful system to recover nonchimera transgenic plants by micropropagation with the use of an adequate selection agent.