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1.
FEMS Microbiol Ecol ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38599638

RESUMO

Coffee leaf rust, caused by the fungus Hemileia vastatrix, became a major concern for coffee-producing countries. Additionally, there is an increase in the resistance of certain races of the fungus to fungicides and breeding cultivars, making producers to use alternative control methods. In this work, we transplanted the leaf surface microbiota of rust-resistant coffee species (Coffea racemosa and Coffea stenophylla) to Coffea arabica and tested whether the new microbiota would be able to minimize the damage caused by H. vastatrix. It was seen that the transplant was successful in controlling rust, especially from C. stenophylla, but the protection depended on the concentration of the microbiota. Certain fungi such as Acrocalymma, Bipolaris, Didymella, Nigrospora, Setophaeosphaeria, Simplicillium, Stagonospora, Torula and bacteria such as Chryseobacterium, Sphingobium and especially Enterobacter and have their populations increased and may be related to the antagonism seen against H. vastatrix. Interestingly, relative population of bacteria from genera Pantoea, Methylobacterium and Sphingomonas decreased after transplant, suggesting a positive interaction between them and H. vastatrix development. Our findings may help to better understand the role of the microbiota in coffee leaf rust as well as help to optimize the development of biocontrol agents.

2.
Anal Biochem ; 675: 115225, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37364681

RESUMO

An efficient method of genomic DNA extraction that provides high quality and yield is a crucial pre-requisite and limiting factor in plant genetic analysis. However, pure genomic DNA can be challenging to obtain from some plant species due to their sugar and secondary metabolite contents. Lippia alba is an important aromatic and medicinal plant, chemically characterized by the presence of tannins, flavonoids, anthocyanins, and essential oils, which interfere with the extraction of pure genomic DNA. In this scenario, optimizing the extraction methods and minimizing the effects of these compounds are necessary. This study compares six plant DNA extraction protocols based on the CTAB method. The quality and quantity of DNA samples obtained were determined by physical appearance by electrophoresis in agarose gels and spectrophotometry. The results highlight the difficulty in obtaining pure and clear bands for all tested methods, except for the polyvinylpyrrolidone (PVP)-based protocol created by our team, which was the better option for obtaining high-quality genomic DNA of L. alba. We conclude that adding PVP-40 into DNA extraction buffers can optimize the DNA extraction of L. alba and indicate this protocol for DNA extraction from other aromatic plants.


Assuntos
Lippia , Óleos Voláteis , Plantas Medicinais , Lippia/genética , Lippia/química , Antocianinas , Óleos Voláteis/química , DNA de Plantas/genética
3.
Curr Microbiol ; 80(4): 130, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36890285

RESUMO

The analysis of large-scale sequence data has revealed that plants over time recruit certain microbes that are efficient colonizers of the rhizosphere. This enrichment phenomenon is especially seen in annual crops, but we suggest that there could have been some type of enrichment in perennial crops such as coffee plants. To verify this hypothesis, we performed a metagenomic and chemical analysis in rhizosphere with three different plant ages (young, mature, and old) and cultivated on the same farm. We verified that from mature to old plants, there was a decrease in diversity, particularly Fusarium and Plenodomus, while there was an increase in Aspergillus, Cladosporium, Metarhizium, and Pseudomonas. We also detected that the abundance of anti-microbials and ACC-deaminase grows as plants age, although denitrification and carbon fixation had reduced abundances. In summary, we detected an enrichment in the microbial community, especially in the great increase in the participation of Pseudomonas, passing from 50% of the relative abundance as the plants get older. Such enrichment can occur through the dynamics of nutrients such as magnesium and boron.


Assuntos
Coffea , Rizosfera
4.
BMC Microbiol ; 22(1): 222, 2022 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-36131235

RESUMO

BACKGROUND: Pseudomonas spp. promotes plant growth and colonizes a wide range of environments. During the annotation of a Coffea arabica ESTs database, we detected a considerable number of contaminant Pseudomonas sequences, specially associated with leaves. The genome of a Pseudomonas isolated from coffee leaves was sequenced to investigate in silico information that could offer insights about bacterial adaptation to coffee phyllosphere. In parallel, several experiments were performed to confirm certain physiological characteristics that could be associated with phyllospheric behavior. Finally, in vivo and in vitro experiments were carried out to verify whether this isolate could serve as a biocontrol agent against coffee rust and how the isolate could act against the infection.  RESULTS: The isolate showed several genes that are associated with resistance to environmental stresses, such as genes encoding heat/cold shock proteins, antioxidant enzymes, carbon starvation proteins, proteins that control osmotic balance and biofilm formation. There was an increase of exopolysaccharides synthesis in response to osmotic stress, which may protect cells from dessication on phyllosphere. Metabolic pathways for degradation and incorporation into citrate cycle of phenolic compounds present in coffee were found, and experimentally confirmed. In addition, MN1F was found to be highly tolerant to caffeine. The experiments of biocontrol against coffee leaf rust showed that the isolate can control the progress of the disease, most likely through competition for resources. CONCLUSION: Genomic analysis and experimental data suggest that there are adaptations of this Pseudomonas to live in association with coffee leaves and to act as a biocontrol agent.


Assuntos
Basidiomycota , Coffea , Antioxidantes , Basidiomycota/genética , Cafeína , Carbono , Citratos , Coffea/microbiologia , Proteínas e Peptídeos de Choque Frio , Genômica , Pseudomonas/genética
5.
Microbiol Res ; 263: 127129, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35907286

RESUMO

Many Pseudomonas species promote plant growth and colonize a wide range of environments. The annotation of a Coffea arabica ESTs database revealed a considerable number of Pseudomonas sequences. To evaluate the genomic and physiology of Pseudomonas that inhabit coffee plants, fluorescent Pseudomonas from C. arabica root environment were isolated. Two of them had their genomes sequenced; one from rhizospheric soil, named as MNR3A, and one from internal part of the root, named as EMN2. In parallel, we performed biochemical and physiological experiments to confirm genomic analyses results. Interestingly, EMN2 has achromobactin and aerobactin siderophore receptors, but does not have the genes responsible for the production of these siderophores, suggesting an interesting bacterial competition strategy. The two bacterial isolates were able to degrade and catabolize plant phenolic compounds for their own benefit. Surprisingly, MNR3A and EMN2 do not contain caffeine methylases that are responsible for the catabolism of caffeine. In fact, bench experiments confirm that the bacteria did not metabolize caffeine, but were resistant and chemically attracted to it. Furthermore, both bacteria, most especially MNR3A, were able to increase growth of lettuce plants. Our results indicate MNR3A as a potential plant growth promoting bacteria.


Assuntos
Coffea , Bactérias/metabolismo , Cafeína/metabolismo , Genômica , Pseudomonas/genética , Pseudomonas/metabolismo , Sideróforos/metabolismo
6.
Microbiol Spectr ; 10(2): e0044422, 2022 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-35289671

RESUMO

Coffee is one of the most important commodities in the global market. Of the 130 species of Coffea, only Coffea arabica and Coffea canephora are actually cultivated on a large scale. Despite the economic and social importance of coffee, little research has been done on the coffee tree microbiome. To assess the structure and function of the rhizosphere microbiome, we performed a deep shotgun metagenomic sequencing of the rhizospheres of five different species, C. arabica, C. canephora, Coffea stenophylla, Coffea racemosa, and Coffea liberica. Our findings indicated that C. arabica and C. stenophylla have different microbiomes, while no differences were detected between the other Coffea species. The core rhizosphere microbiome comprises genera such as Streptomyces, Mycobacterium, Bradyrhizobium, Burkholderia, Sphingomonas, Penicillium, Trichoderma, and Rhizophagus, several of which are potential plant-beneficial microbes. Streptomyces and mycorrhizal fungi dominate the microbial communities. The concentration of sucrose in the rhizosphere seems to influence fungal communities, and the concentration of caffeine/theobromine has little effect on the microbiome. We also detected a possible relationship between drought tolerance in Coffea and known growth-promoting microorganisms. The results provide important information to guide future studies of the coffee tree microbiome to improve plant production and health. IMPORTANCE The microbiome has been identified as a fundamental factor for the maintenance of plant health, helping plants to fight diseases and the deleterious effects of abiotic stresses. Despite this, in-depth studies of the microbiome have been limited to a few species, generally with a short life cycle, and perennial species have mostly been neglected. The coffee tree microbiome, on the other hand, has gained interest in recent years as Coffea trees are perennial tropical species of enormous importance, especially for developing countries. A better understanding of the microorganisms associated with coffee trees can help to mitigate the deleterious effects of climate change on the crop, improving plant health and making the system more sustainable.


Assuntos
Coffea , Micobioma , Café/química , Rizosfera , Árvores
7.
Sci Rep ; 9(1): 8446, 2019 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-31186437

RESUMO

Coffea arabica is an allotetraploid of high economic importance. C. arabica transcriptome is a combination of the transcripts of two parental genomes (C. eugenioides and C. canephora) that gave rise to the homeologous genes of the species. Previous studies have reported the transcriptional dynamics of C. arabica. In these reports, the ancestry of homeologous genes was identified and the overall regulation of homeologous differential expression (HDE) was explored. One of these genes is part of the FRIGIDA-like family (FRL), which includes the Arabidopsis thaliana flowering-time regulation protein, FRIGIDA (FRI). As nonfunctional FRI proteins give rise to rapid-cycling summer annual ecotypes instead of vernalization-responsive winter-annuals, allelic variation in FRI can modulate flowering time in A. thaliana. Using bioinformatics, genomic analysis, and the evaluation of gene expression of homeologs, we characterized the FRL gene family in C. arabica. Our findings indicate that C. arabica expresses 10 FRL homeologs, and that, throughout flower and fruit development, these genes are differentially transcribed. Strikingly, in addition to confirming the expression of FRL genes during zygotic embryogenesis, we detected FRL expression during direct somatic embryogenesis, a novel finding regarding the FRL gene family. The HDE profile of FRL genes suggests an intertwined homeologous gene regulation. Furthermore, we observed that FLC gene of C. arabica has an expression profile similar to that of CaFRL genes.


Assuntos
Proteínas de Arabidopsis/genética , Coffea/crescimento & desenvolvimento , Desenvolvimento Vegetal/genética , Técnicas de Embriogênese Somática de Plantas , Arabidopsis/genética , Coffea/genética , Flores/genética , Regulação da Expressão Gênica de Plantas/genética , Genes de Plantas , Genoma de Planta , Reprodução/genética , Transcriptoma/genética
8.
Genet Mol Biol ; 41(2): 455-465, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29782032

RESUMO

Coffee is one of the most valuable agricultural commodities and the plants' leaves are the primary site of infection for most coffee diseases, such as the devastating coffee leaf rust. Therefore, the use of bacterial microbiota that inhabits coffee leaves to fight infections could be an alternative agricultural method to protect against coffee diseases. Here, we report the leaf-associated bacteria in three coffee genotypes over the course of a year, with the aim to determine the diversity of bacterial microbiota. The results indicate a prevalence of Enterobacteriales in Coffea canephora, Pseudomonadales in C. arabica 'Obatã', and an intriguing lack of bacterial dominance in C. arabica 'Catuaí'. Using PERMANOVA analyses, we assessed the association between bacterial abundance in the coffee genotypes and environmental parameters such as temperature, precipitation, and mineral nutrients in the leaves. We detected a close relationship between the amount of Mn and the abundance of Pseudomonadales in 'Obatã' and the amount of Ca and the abundance of Enterobacteriales in C. canephora. We suggest that mineral nutrients can be key drivers that shape leaf microbial communities.

9.
Biochem Biophys Res Commun ; 466(4): 629-36, 2015 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-26367180

RESUMO

Thaumatin-like proteins (TLPs) are found in diverse eukaryotes. Plant TLPs, known as Pathogenicity Related Protein (PR-5), are considered fungal inhibitors. However, genes encoding TLPs are frequently found in fungal genomes. In this work, we have identified that Moniliophthora perniciosa, a basidiomycete pathogen that causes the Witches' Broom Disease (WBD) of cacao, presents thirteen putative TLPs from which four are expressed during WBD progression. One of them is similar to small TLPs, which are present in phytopathogenic basidiomycete, such as wheat stem rust fungus Puccinia graminis. Fungi genomes annotation and phylogenetic data revealed a larger number of TLPs in basidiomycetes when comparing with ascomycetes, suggesting that these proteins could be involved in specific traits of mushroom-forming species. Based on the present data, we discuss the contribution of TLPs in the combat against fungal competitors and hypothesize a role of these proteins in M. perniciosa pathogenicity.


Assuntos
Agaricales/genética , Agaricales/patogenicidade , Cacau/microbiologia , Proteínas Fúngicas/genética , Genoma Fúngico , Doenças das Plantas/microbiologia , Sequência de Aminoácidos , Proteínas Fúngicas/fisiologia , Expressão Gênica , Dados de Sequência Molecular , Família Multigênica , Filogenia , RNA Fúngico/genética , Homologia de Sequência de Aminoácidos , Virulência/genética , Virulência/fisiologia
10.
Plant Cell ; 26(11): 4245-69, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25371547

RESUMO

Witches' broom disease (WBD), caused by the hemibiotrophic fungus Moniliophthora perniciosa, is one of the most devastating diseases of Theobroma cacao, the chocolate tree. In contrast to other hemibiotrophic interactions, the WBD biotrophic stage lasts for months and is responsible for the most distinctive symptoms of the disease, which comprise drastic morphological changes in the infected shoots. Here, we used the dual RNA-seq approach to simultaneously assess the transcriptomes of cacao and M. perniciosa during their peculiar biotrophic interaction. Infection with M. perniciosa triggers massive metabolic reprogramming in the diseased tissues. Although apparently vigorous, the infected shoots are energetically expensive structures characterized by the induction of ineffective defense responses and by a clear carbon deprivation signature. Remarkably, the infection culminates in the establishment of a senescence process in the host, which signals the end of the WBD biotrophic stage. We analyzed the pathogen's transcriptome in unprecedented detail and thereby characterized the fungal nutritional and infection strategies during WBD and identified putative virulence effectors. Interestingly, M. perniciosa biotrophic mycelia develop as long-term parasites that orchestrate changes in plant metabolism to increase the availability of soluble nutrients before plant death. Collectively, our results provide unique insight into an intriguing tropical disease and advance our understanding of the development of (hemi)biotrophic plant-pathogen interactions.


Assuntos
Agaricales/fisiologia , Cacau/genética , Interações Hospedeiro-Patógeno , Doenças das Plantas/microbiologia , Transcriptoma , Agaricales/patogenicidade , Sequência de Bases , Cacau/citologia , Cacau/microbiologia , Análise por Conglomerados , Perfilação da Expressão Gênica , Regulação Fúngica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Sequenciamento de Nucleotídeos em Larga Escala , Modelos Biológicos , Dados de Sequência Molecular , Micélio , Fotossíntese , Proteínas de Plantas/metabolismo , Análise de Sequência de RNA , Virulência
11.
DNA Res ; 20(6): 567-81, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23857904

RESUMO

We present the sequencing and annotation of the Leishmania (Leishmania) amazonensis genome, an etiological agent of human cutaneous leishmaniasis in the Amazon region of Brazil. L. (L.) amazonensis shares features with Leishmania (L.) mexicana but also exhibits unique characteristics regarding geographical distribution and clinical manifestations of cutaneous lesions (e.g. borderline disseminated cutaneous leishmaniasis). Predicted genes were scored for orthologous gene families and conserved domains in comparison with other human pathogenic Leishmania spp. Carboxypeptidase, aminotransferase, and 3'-nucleotidase genes and ATPase, thioredoxin, and chaperone-related domains were represented more abundantly in L. (L.) amazonensis and L. (L.) mexicana species. Phylogenetic analysis revealed that these two species share groups of amastin surface proteins unique to the genus that could be related to specific features of disease outcomes and host cell interactions. Additionally, we describe a hypothetical hybrid interactome of potentially secreted L. (L.) amazonensis proteins and host proteins under the assumption that parasite factors mimic their mammalian counterparts. The model predicts an interaction between an L. (L.) amazonensis heat-shock protein and mammalian Toll-like receptor 9, which is implicated in important immune responses such as cytokine and nitric oxide production. The analysis presented here represents valuable information for future studies of leishmaniasis pathogenicity and treatment.


Assuntos
Genoma de Protozoário , Leishmania/genética , Interações Hospedeiro-Parasita , Humanos , Leishmania/metabolismo , Leishmaniose Cutânea/parasitologia , Modelos Genéticos , Anotação de Sequência Molecular , Dados de Sequência Molecular , Filogenia
12.
Theor Appl Genet ; 126(10): 2451-65, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23832048

RESUMO

Angular leaf spot (ALS) causes major yield losses in the common bean (Phaseolus vulgaris L.), an important protein source in the human diet. This study describes the saturation around a major quantitative trait locus (QTL) region, ALS10.1, controlling resistance to ALS located on linkage group Pv10 and explores the genomic context of this region using available data from the P. vulgaris genome sequence. DArT-derived markers (STS-DArT) selected by bulk segregant analysis and SCAR and SSR markers were used to increase the resolution of the QTL, reducing the confidence interval of ALS10.1 from 13.4 to 3.0 cM. The position of the SSR ATA220 coincided with the maximum LOD score of the QTL. Moreover, a new QTL (ALS10.2(UC)) was identified at the end of the same linkage group. Sequence analysis using the P. vulgaris genome located ten SSRs and seven STS-DArT on chromosome 10 (Pv10). Coincident linkage and genome positions of five markers enabled the definition of a core region for ALS10.1 spanning 5.3 Mb. These markers are linked to putative genes related to disease resistance such as glycosyl transferase, ankyrin repeat-containing, phospholipase, and squamosa-promoter binding protein. Synteny analysis between ALS10.1 markers and the genome of soybean suggested a dynamic evolution of this locus in the common bean. The present study resulted in the identification of new candidate genes and markers closely linked to a major ALS disease resistance QTL, which can be used in marker-assisted selection, fine mapping and positional QTL cloning.


Assuntos
Resistência à Doença/genética , Phaseolus/genética , Phaseolus/microbiologia , Doenças das Plantas/genética , Folhas de Planta/genética , Folhas de Planta/microbiologia , Locos de Características Quantitativas/genética , Cromossomos de Plantas/genética , Duplicação Gênica/genética , Genes de Plantas/genética , Ligação Genética , Marcadores Genéticos , Genótipo , Humanos , Repetições de Microssatélites/genética , Phaseolus/imunologia , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Folhas de Planta/imunologia , Reação em Cadeia da Polimerase , Polimorfismo Genético , Sintenia/genética
13.
Mol Plant Pathol ; 14(6): 602-9, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23573899

RESUMO

Members of the pathogenesis-related protein 1 (PR-1) family are well-known markers of plant defence responses, forming part of the arsenal of the secreted proteins produced on pathogen recognition. Here, we report the identification of two cacao (Theobroma cacao L.) PR-1s that are fused to transmembrane regions and serine/threonine kinase domains, in a manner characteristic of receptor-like kinases (RLKs). These proteins (TcPR-1f and TcPR-1g) were named PR-1 receptor kinases (PR-1RKs). Phylogenetic analysis of RLKs and PR-1 proteins from cacao indicated that PR-1RKs originated from a fusion between sequences encoding PR-1 and the kinase domain of a LecRLK (Lectin Receptor-Like Kinase). Retrotransposition marks surround TcPR-1f, suggesting that retrotransposition was involved in the origin of PR-1RKs. Genes with a similar domain architecture to cacao PR-1RKs were found in rice (Oryza sativa), barrel medic (Medicago truncatula) and a nonphototrophic bacterium (Herpetosiphon aurantiacus). However, their kinase domains differed from those found in LecRLKs, indicating the occurrence of convergent evolution. TcPR-1g expression was up-regulated in the biotrophic stage of witches' broom disease, suggesting a role for PR-1RKs during cacao defence responses. We hypothesize that PR-1RKs transduce a defence signal by interacting with a PR-1 ligand.


Assuntos
Cacau/enzimologia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Filogenia , Doenças das Plantas , Proteínas de Plantas/classificação
14.
BMC Genomics ; 14: 201, 2013 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-23521840

RESUMO

BACKGROUND: Eucalyptus is one of the most important sources of industrial cellulose. Three species of this botanical group are intensively used in breeding programs: E. globulus, E. grandis and E. urophylla. E. globulus is adapted to subtropical/temperate areas and is considered a source of high-quality cellulose; E. grandis grows rapidly and is adapted to tropical/subtropical climates; and E. urophylla, though less productive, is considered a source of genes related to robustness. Wood, or secondary xylem, results from cambium vascular differentiation and is mostly composed of cellulose, lignin and hemicelluloses. In this study, the xylem transcriptomes of the three Eucalyptus species were investigated in order to provide insights on the particularities presented by each of these species. RESULTS: Data analysis showed that (1) most Eucalyptus genes are expressed in xylem; (2) most genes expressed in species-specific way constitutes genes with unknown functions and are interesting targets for future studies; (3) relevant differences were observed in the phenylpropanoid pathway: E. grandis xylem presents higher expression of genes involved in lignin formation whereas E. urophylla seems to deviates the pathway towards flavonoid formation; (4) stress-related genes are considerably more expressed in E. urophylla, suggesting that these genes may contribute to its robustness. CONCLUSIONS: The comparison of these three transcriptomes indicates the molecular signatures underlying some of their distinct wood characteristics. This information may contribute to the understanding of xylogenesis, thus increasing the potential of genetic engineering approaches aiming at the improvement of Eucalyptus forest plantations productivity.


Assuntos
Eucalyptus/genética , Transcriptoma , Parede Celular/genética , Parede Celular/metabolismo , Mapeamento de Sequências Contíguas , Bases de Dados Factuais , Eucalyptus/metabolismo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Análise de Sequência de RNA , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Xilema/genética , Xilema/metabolismo
15.
Genet Mol Biol ; 35(1 (suppl)): 331-4, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22802718

RESUMO

The legume Glycine max (soybean) plays an important economic role in the international commodities market, with a world production of almost 260 million tons for the 2009/2010 harvest. The increase in drought events in the last decade has caused production losses in recent harvests. This fact compels us to understand the drought tolerance mechanisms in soybean, taking into account its variability among commercial and developing cultivars. In order to identify single nucleotide polymorphisms (SNPs) in genes up-regulated during drought stress, we evaluated suppression subtractive libraries (SSH) from two contrasting cultivars upon water deprivation: sensitive (BR 16) and tolerant (Embrapa 48). A total of 2,222 soybean genes were up-regulated in both cultivars. Our method identified more than 6,000 SNPs in tolerant and sensitive Brazilian cultivars in those drought stress related genes. Among these SNPs, 165 (in 127 genes) are positioned at soybean chromosome ends, including transcription factors (MYB, WRKY) related to tolerance to abiotic stress.

16.
Planta ; 233(1): 123-37, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20931223

RESUMO

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.


Assuntos
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 DNA
17.
Genet. mol. biol ; 34(1): 88-102, 2011. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-573697

RESUMO

A wide array of molecular markers has been used to investigate the genetic diversity among common bean species. However, the best combination of markers for studying such diversity among common bean cultivars has yet to be determined. Few reports have examined the genetic diversity of the carioca bean, commercially one of the most important common beans in Brazil. In this study, we examined the usefulness of two molecular marker systems (simple sequence repeats - SSRs and amplified fragment length polymorphisms - AFLPs) for assessing the genetic diversity of carioca beans. The amount of information provided by Roger's modified genetic distance was used to analyze SSR data and Jaccards similarity coefficient was used for AFLP data. Seventy SSRs were polymorphic and 20 AFLP primer combinations produced 635 polymorphic bands. Molecular analysis showed that carioca genotypes were quite diverse. AFLPs revealed greater genetic differentiation and variation within the carioca genotypes (Gst = 98 percent and Fst = 0.83, respectively) than SSRs and provided better resolution for clustering the carioca genotypes. SSRs and AFLPs were both suitable for assessing the genetic diversity of Brazilian carioca genotypes since the number of markers used in each system provided a low coefficient of variation. However, fingerprint profiles were generated faster with AFLPs, making them a better choice for assessing genetic diversity in the carioca germplasm.

18.
Plant Physiol ; 154(3): 1053-66, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20864545

RESUMO

Polyploidization constitutes a common mode of evolution in flowering plants. This event provides the raw material for the divergence of function in homeologous genes, leading to phenotypic novelty that can contribute to the success of polyploids in nature or their selection for use in agriculture. Mounting evidence underlined the existence of homeologous expression biases in polyploid genomes; however, strategies to analyze such transcriptome regulation remained scarce. Important factors regarding homeologous expression biases remain to be explored, such as whether this phenomenon influences specific genes, how paralogs are affected by genome doubling, and what is the importance of the variability of homeologous expression bias to genotype differences. This study reports the expressed sequence tag assembly of the allopolyploid Coffea arabica and one of its direct ancestors, Coffea canephora. The assembly was used for the discovery of single nucleotide polymorphisms through the identification of high-quality discrepancies in overlapped expressed sequence tags and for gene expression information indirectly estimated by the transcript redundancy. Sequence diversity profiles were evaluated within C. arabica (Ca) and C. canephora (Cc) and used to deduce the transcript contribution of the Coffea eugenioides (Ce) ancestor. The assignment of the C. arabica haplotypes to the C. canephora (CaCc) or C. eugenioides (CaCe) ancestral genomes allowed us to analyze gene expression contributions of each subgenome in C. arabica. In silico data were validated by the quantitative polymerase chain reaction and allele-specific combination TaqMAMA-based method. The presence of differential expression of C. arabica homeologous genes and its implications in coffee gene expression, ontology, and physiology are discussed.


Assuntos
Coffea/genética , Etiquetas de Sequências Expressas , Genoma de Planta , Polimorfismo de Nucleotídeo Único , DNA de Plantas/genética , Mineração de Dados , Regulação da Expressão Gênica de Plantas , Frequência do Gene , Haplótipos , Análise de Sequência de DNA , Tetraploidia
19.
J Mol Evol ; 70(1): 85-97, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20033398

RESUMO

Moniliophthora perniciosa and Moniliophthora roreri are phytopathogenic basidiomycete species that infect cacao causing two important diseases in this crop: "Witches' Broom" and "Frosty Pod Rot", respectively. The ability of species from this genus (Moniliophthora) to cause disease is exceptional in the family Marasmiaceae. Species in closely related genera including, Marasmius, Crinipellis, and Chaetocalathus, are mainly saprotrophs and are not known to cause disease. In this study, the possibility that this phytopathogenic lifestyle has been acquired by horizontal gene transfer (HGT) was investigated. A stringent genome comparison pipeline was used to identify potential genes that have been obtained by Moniliophthora through HGT. This search led to the identification of three genes: a metallo-dependent hydrolase (MDH), a mannitol phosphate dehydrogenase (MPDH), and a family of necrosis-inducing proteins (NEPs). Phylogenetic analysis of these genes suggests that Moniliophthora acquired NEPs from oomycetes, MDH from actinobacteria and MPDH from firmicutes. Based on the known gene functions and on previous studies of M. perniciosa infection and development, a correlation between gene acquisition and the evolution of the phytopathogenic genus Moniliophthora can be postulated.


Assuntos
Basidiomycota/genética , Basidiomycota/patogenicidade , Evolução Biológica , Cacau/microbiologia , Transferência Genética Horizontal/genética , Genes Fúngicos/genética , Basidiomycota/enzimologia , Teorema de Bayes , Proteínas Fúngicas/genética , Hidrolases/genética , Necrose , Oxirredutases/genética , Filogenia
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