RESUMO
Soybean is globally cultivated primarily for its protein and oil. The protein and oil contents of the seeds are quantitatively inherited traits determined by the interaction of numerous genes. In order to gain a better understanding of the molecular foundation of soybean protein and oil content for the marker-assisted selection (MAS) of high quality traits, a population of 185 soybean germplasms was evaluated to identify the quantitative trait loci (QTLs) associated with the seed protein and oil contents. Using specific length amplified fragment sequencing (SLAF-seq) technology, a total of 12,072 single nucleotide polymorphisms (SNPs) with a minor allele frequency (MAF)â¯≥â¯0.05 were detected across the 20 chromosomes (Chr), with a marker density of 78.7 kbp. A total of 31 SNPs located on 12 of the 20 soybean chromosomes were correlated with seed protein and oil content. Of the 31 SNPs that were associated with the two target traits, 31 beneficial alleles were identified. Two SNP markers, namely rs15774585 and rs15783346 on Chr 07, were determined to be related to seed oil content both in 2015 and 2016. Three SNP markers, rs53140888 on Chr 01, rs19485676 on Chr 13, and rs24787338 on Chr 20 were correlated with seed protein content both in 2015 and 2016. These beneficial alleles may potentially contribute towards the MAS of favorable soybean protein and oil characteristics.
Assuntos
Mapeamento Cromossômico , Genoma de Planta , Estudo de Associação Genômica Ampla , Glycine max/genética , Óleo de Soja/genética , Proteínas de Soja/genética , Biomarcadores , Cromossomos de Plantas/genética , Genótipo , Herança Multifatorial , Estruturas Vegetais/genética , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Sementes/genética , Seleção GenéticaRESUMO
Fifteen tissues of 4-year-old fruit repining stage Jilin ginseng were chosen as materials, six kinds of monomer saponins (ginsenosides Rg1, Re, Rb1, Rc, Rb2 and Rd) content in 15 tissues was measured by HPLC and vanillin-sulfuric acid method. The relative expression of FPS, SQS, SQE, OSC, ß-AS and P450 genes in 15 tissues was analyzed by real-time PCR. The correlations between ginseng saponin content in 15 tissues of Jilin ginseng and biosynthetic pathway -related genes were obtained. The results showed that was a synergistic increase and decrease trend of positive linear correlation among six kinds of monomer saponin content, and there was a significantly (P < 0.01) positive correlation between monomer saponin content and total saponins content. Monomer saponin content and 6 kinds of enzyme gene correlation were different. Biosynthesis of ginseng total saponins and monomer saponin were regulated by six kinds of participation ginsenoside biosynthesis enzyme genes, the expression of these six kinds of genes in different tissues of ginseng showed collaborative increase and decrease trend, and regulated biosynthesis of ginseng ginsenoside by group coordinative manner.
Assuntos
Medicamentos de Ervas Chinesas/análise , Panax/genética , Proteínas de Plantas/genética , Saponinas/análise , Perfilação da Expressão Gênica , Panax/química , Panax/metabolismo , Proteínas de Plantas/metabolismo , Estruturas Vegetais/química , Estruturas Vegetais/genética , Estruturas Vegetais/metabolismo , Plantas Medicinais/química , Plantas Medicinais/genética , Plantas Medicinais/metabolismo , Saponinas/metabolismoRESUMO
BACKGROUND: Panax ginseng C. A. Meyer is one of the most widely used medicinal plants. Complete genome information for this species remains unavailable due to its large genome size. At present, analysis of expressed sequence tags is still the most powerful tool for large-scale gene discovery. The global expressed sequence tags from P. ginseng tissues, especially those isolated from stems, leaves and flowers, are still limited, hindering in-depth study of P. ginseng. RESULTS: Two 454 pyrosequencing runs generated a total of 2,423,076 reads from P. ginseng roots, stems, leaves and flowers. The high-quality reads from each of the tissues were independently assembled into separate and shared contigs. In the separately assembled database, 45,849, 6,172, 4,041 and 3,273 unigenes were only found in the roots, stems, leaves and flowers database, respectively. In the jointly assembled database, 178,145 unigenes were observed, including 86,609 contigs and 91,536 singletons. Among the 178,145 unigenes, 105,522 were identified for the first time, of which 65.6% were identified in the stem, leaf or flower cDNA libraries of P. ginseng. After annotation, we discovered 223 unigenes involved in ginsenoside backbone biosynthesis. Additionally, a total of 326 potential cytochrome P450 and 129 potential UDP-glycosyltransferase sequences were predicted based on the annotation results, some of which may encode enzymes responsible for ginsenoside backbone modification. A BLAST search of the obtained high-quality reads identified 14 potential microRNAs in P. ginseng, which were estimated to target 100 protein-coding genes, including transcription factors, transporters and DNA binding proteins, among others. In addition, a total of 13,044 simple sequence repeats were identified from the 178,145 unigenes. CONCLUSIONS: This study provides global expressed sequence tags for P. ginseng, which will contribute significantly to further genome-wide research and analyses in this species. The novel unigenes identified here enlarge the available P. ginseng gene pool and will facilitate gene discovery. In addition, the identification of microRNAs and the prediction of targets from this study will provide information on gene transcriptional regulation in P. ginseng. Finally, the analysis of simple sequence repeats will provide genetic makers for molecular breeding and genetic applications in this species.
Assuntos
Perfilação da Expressão Gênica , Ginsenosídeos/biossíntese , MicroRNAs/genética , Repetições de Microssatélites/genética , Panax/genética , Panax/metabolismo , Cruzamento , Etiquetas de Sequências Expressas/metabolismo , Genes de Plantas/genética , Anotação de Sequência Molecular , Especificidade de Órgãos , Estruturas Vegetais/genéticaRESUMO
Maytenus ilicifolia e M. aquifolium (espinheira-santa) são espécies medicinais nativas do Brasil ameaçadas de extinção devido à forte ação antrópica nas populações naturais. O objetivo deste trabalho foi avaliar a divergência genética em germoplasma de espinheira-santa, e agrupar os acessos através de análises multivariadas, com base em caracteres morfo-fisiológicos das progênies. Foram avaliados 89 acessos do banco ativo de germoplasma de espinheira-santa da Embrapa Clima Temperado/Universidade Federal de Pelotas. Os caracteres avaliados foram dias da semeadura à emergência; altura e diâmetro à base do caule, aos 90, 180, 270 e 360 dias; crescimento em altura e diâmetro à base do caule; comprimento e largura de folha e número de espinhos por folha. O delineamento experimental foi em blocos casualizados, com quatro repetições e cinco plantas por parcela. Os dados foram submetidos à análise de variância e análise de variância multivariada, sendo estimadas as variáveis canônicas. Os caracteres avaliados foram eficientes para separar os acessos em três grupos. As variáveis altura, diâmetro à base do caule aos 360 dias e número de folhas aos 180 dias são as mais importantes para caracterização do germoplasma de espinheira-santa.
Maytenus ilicifolia and M. aquifolium (espinheira-santa) are medicinal species native to Brazil. They are endangered due to the strong anthropic action in natural populations. The aim of this work was to evaluate the genetic divergence in "espinheira-santa" germplasm and to cluster accessions by multivariate analyses based on morphophysiological traits of progenies. Eighty-nine accessions of the "espinheira-santa" active germplasm bank from the Brazilian Agricultural Research Corporation (EMBRAPA) Temperate Agriculture, Pelotas Federal University, Pelotas Municipality, Rio Grande do Sul State, Brazil, were evaluated regarding days from sowing to emergence; height and stem-base diameter at 90, 180, 270 and 360 days; height and stem-base diameter growth; leaf length and width; and number of thorns per leaf. Experimental design was in randomized blocks, with four replicates and five plants per plot. The results were subjected to analysis of variance and multivariate analysis of variance, and canonical variables were estimated. The evaluated traits were efficient for separating the accessions into three clusters. Height and stem-basal diameter at 360 days and leaf number at 180 days were the most important for "espinheira-santa" germplasm characterization.
Assuntos
Estruturas Vegetais/genética , Maytenus , Fisiologia , Variação Genética/genética , Genética/organização & administração , Análise MultivariadaRESUMO
BACKGROUND: Pistacia vera 'Kerman' is the predominant pistachio nut cultivar in the United States (California), the world's second largest producer. Despite several reports on the essential oil (EO) content in the genus Pistacia, data on 'Kerman' are limited. The EO content and volatile organic compound (VOC) emissions of tree nut orchards are of current interest to researchers investigating insect pests and the potential role of EO and VOCs as semiochemicals. To establish a basis for the VOC output of pistachios, the EO content of fruits, peduncles, and leaves was analyzed. RESULTS: Evaluated plant parts contained limonene as the primary EO component, followed by alpha-terpinolene. Peduncles were unique in containing relatively high levels of alpha-thujene. The results were reproducible between two different geographical locations. In situ solid phase microextraction (SPME) studies demonstrated the volatile emission was representative of the EO composition. CONCLUSION: This is the first report detailing the content and distribution of EO and the unique limonene-dominant profile for this Pistacia vera cultivar which may influence pistachio insect pest semiochemical research.
Assuntos
Óleos Voláteis/análise , Pistacia/química , Extratos Vegetais/análise , Estruturas Vegetais/química , Animais , California , Cicloexenos/análise , Genótipo , Geografia , Controle de Insetos , Insetos , Limoneno , Óleos Voláteis/química , Pistacia/genética , Extratos Vegetais/química , Estruturas Vegetais/genética , Terpenos/análise , Compostos Orgânicos Voláteis/química , VolatilizaçãoRESUMO
A cDNA clone containing a catalase (CAT1) gene, designated PgCat1, was isolated from Panax ginseng C.A. Meyer (Korean ginseng). PgCat1 is predicted to encode a precursor protein of 492 amino acid residues, and its sequence shares high degrees of homology with a number of other CAT1s. Genomic DNA hybridization analysis indicated that PgCat1 represents a multi-gene family. Reverse transcriptase (RT)-PCR results showed that PgCat1 expressed at different levels in leaves, stem, roots of P. ginseng seedlings. Different stresses, heavy metals, plant hormones, osmotic agents, high light irradiance, abiotic stresses, triggered a significant induction of PgCat1. The positive responses of PgCat1 to the various stimuli suggested that P. ginseng PgCat1 may help to protect the plant against reactive oxidant related environmental stresses.
Assuntos
Adaptação Fisiológica/genética , Catalase/genética , DNA de Plantas/isolamento & purificação , Expressão Gênica , Genes de Plantas , Panax/genética , Proteínas de Plantas/genética , Estresse Fisiológico/genética , Sequência de Aminoácidos , Sequência de Bases , Catalase/metabolismo , DNA Complementar , Genoma de Planta , Dados de Sequência Molecular , Família Multigênica , Estresse Oxidativo/genética , Panax/metabolismo , Proteínas de Plantas/metabolismo , Estruturas Vegetais/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência , Homologia de SequênciaRESUMO
The distribution of phenolic compounds in young and developing leaves, stems, main and lateral roots and cotyledons of 8-week-old tea (Camellia sinensis) seedlings was investigated using HPLC-MS(2). Fourteen compounds, flavan-3-ols, chlorogenic acids, and kaempferol-O-glycosides, were identified on the basis of their retention time, absorbance spectrum, and MS fragmentation pattern. The major phenolics were (-)-epigallocatechin-3-O-gallate and (-)-epicatechin-3-O-gallate, located principally in the green parts of the seedlings. Considerable amounts of radioactivity from [ring-(14)C]phenylalanine were incorporated in (-)-epicatechin, (-)-epigallocatechin, (-)-epicatechin-3-O-gallate and (-)-epigallocatechin-3-O-gallate, by tissues of young and developing leaves and stems. Expression of genes encoding enzymes involved in flavan-3-ol biosynthesis, CHS, CHI, F3H, F3'5'H, DFR, ANS, ANR and LAR was investigated. Transcripts of all genes, except LAR, were more abundant in leaves and stems than in roots and cotyledons. No significant difference was found in the amount of transcript of LAR. These findings indicate that in tea seedlings flavan-3-ols are produced by a naringenin-chalcone-->naringenin-->dihydrokaempferol pathway. Dihydrokaempferol is a branch point in the synthesis of (-)-epigallocatechin-3-O-gallate and other flavan-3-ols which can be formed by routes beginning with either a flavonoid 3'-hydroxylase mediated conversion of the flavonol to dihydroquercetin or a flavonoid 3',5'-hydroxylase-catalysed conversion to dihydromyricetin with subsequent steps involving sequential reactions catalysed by dihydroflavanol 4-reductase, anthocyanidin synthase, anthocyanidin reductase and flavan-3-ol gallate synthase.
Assuntos
Camellia sinensis/química , Flavonoides/análise , Expressão Gênica , Genes de Plantas , Fenóis/análise , Plântula/química , Camellia sinensis/genética , Camellia sinensis/metabolismo , Cromatografia Líquida de Alta Pressão , Flavonoides/biossíntese , Fenilalanina/metabolismo , Estruturas Vegetais/química , Estruturas Vegetais/genética , Plântula/genéticaRESUMO
Myrothecium roridum and M. verrucaria are two plant pathogenic species causing foliar spots in a large number of cultivated plants. This paper aims to study the causal agents of foliar spots in vegetable crops (sweet pepper, tomato and cucumber), ornamental plants (Spathiphyllum wallisii, Solidago canadensis, Anthurium andreanum, Dieffenbachia amoena) and a solanaceous weed plant (Nicandra physaloides). Most of the isolates were identified as M. roridum; only the isolate 'Myr-02' from S. canadensis was identified as M. verrucaria. All the isolates were pathogenic to their original plant hosts and also to some other plants. Some fungicides were tested in vitro against an isolate of M. roridum and the mycelial growth recorded after seven days. Fungicides with quartenary ammonium, tebuconazole and copper were highly effective in inhibiting the mycelial growth of M. roridum. This paper confirms the first record of M. roridum causing leaf spots in sweet pepper, tomato, Spathiphyllum, Anthurium, Dieffenbachia and N. physaloides in Brazil. We also report M. roridum as causal agent of cucumber fruit rot and M. verrucaria as a pathogen of tango plants.
Assuntos
Doenças das Plantas/etiologia , Estruturas Vegetais/genética , Fungicidas Industriais , Técnicas In Vitro , Micélio/crescimento & desenvolvimento , Micélio/isolamento & purificação , Folhas de Planta , Plantas Comestíveis , Solidago/crescimento & desenvolvimento , Métodos , Métodos , Verduras , VirulênciaRESUMO
It has been documented that the plant-specific NAC (for NAM, ATAF1,2 and CUC2) transcription factors play an important role in plant development and stress responses. In this study, a chickpea NAC gene CarNAC5 (for Cicer arietinum L. NAC gene 5) was isolated from a cDNA library from chickpea leaves treated by polyethylene glycol (PEG). CarNAC5, as a single/low copy gene, contained three exons and two introns within genomic DNA sequence and encoded a polypeptide with 291 amino acids. CarNAC5 protein had a conserved NAC domain in the N-terminus and showed high similarity to other NACs, especially ATAF subgroup members. The CarNAC5:GFP fusion protein was localized in the nucleus of onion epidermal cells. Furthermore, CarNAC5 protein activated the reporter genes LacZ and HIS3 in yeast. The transactivation activity was mapped to the C-terminal region. The transcripts of CarNAC5 appeared in many chickpea tissues including seedling leaves, stems, roots, flowers, seeds and pods, but mostly accumulated in flowers. Meanwhile, CarNAC5 was strongly expressed during seed maturation and in embryos of the early germinating seeds. It was also significantly induced by drought, heat, wounding, salicylic acid (SA), and indole-3-acetic acid (IAA) treatments. Our results suggest that CarNAC5 encodes a novel NAC-domain protein and acts as a transcriptional activator involved in plant developmental regulation and various stress responses.
Assuntos
Adaptação Fisiológica/genética , Cicer/genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Fatores de Transcrição/genética , Fatores de Transcrição/isolamento & purificação , Sequência de Aminoácidos , Sequência de Bases , Sequência Conservada , DNA Complementar , Éxons , Biblioteca Gênica , Genes Reporter , Íntrons , Dados de Sequência Molecular , Família Multigênica , Cebolas/citologia , Cebolas/genética , Estruturas Vegetais/genética , Sementes , Homologia de Sequência , Estresse Fisiológico , Fatores de Transcrição/metabolismo , Leveduras/genéticaRESUMO
A SiPf40 gene was identified from an immature seed cDNA library of foxtail millet (Setaria italica). This gene encodes for a 29.4 KDa protein containing eight potential transmembrane domains and a highly conserved ZIP signature motif typical of ZIPs (zinc or iron transporter proteins) family. Other SiPf40 potential homologous genes have also been identified in rice, maize, wheat and Arabidopsis by Southern analysis. Expression data showed that this gene is preferentially expressed in millet hypocotyl and bud; however, a minimal level of constitutive expression could be detected in other foxtail millet tissues. Overexpression of SiPf40 gene causes extra branches in tobacco and extra tillering in millet associated with vessel enlarging and xylary fibers increasing, whereas the tiller number decreases in SiPf40 gene silenced plants. Moreover, IAA content decreased significantly in shoot apex of the transgenic tobacco overexpressing SiPf40 gene. All together, these morphological alterations indicate that SiPf40 gene is essential for lateral shoots growth.
Assuntos
Expressão Gênica , Genes de Plantas , Proteínas de Membrana Transportadoras/genética , Nicotiana/metabolismo , Estruturas Vegetais/metabolismo , Setaria (Planta)/metabolismo , Fatores de Transcrição/metabolismo , Motivos de Aminoácidos , Proteínas de Transporte/genética , DNA Complementar , Biblioteca Gênica , Ácidos Indolacéticos/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Estruturas Vegetais/genética , Estruturas Vegetais/crescimento & desenvolvimento , Plantas Geneticamente Modificadas , Sementes , Homologia de Sequência , Setaria (Planta)/genética , Setaria (Planta)/crescimento & desenvolvimento , Nicotiana/genética , Nicotiana/crescimento & desenvolvimentoRESUMO
A cotton (Gossypium hirsutum L.) genomic clone encompassing a 17.9-kb DNA fragment was found to contain a delta-12 fatty acid desaturase gene (designated FAD2-4). The FAD2-4 open reading frame has 1,155bp and is uninterrupted, encoding a conceptual FAD2-4 polypeptide of 384 amino acids that has 98% identity with the cotton FAD2-3 polypeptide. The FAD2-4 gene has a single intron of 2,780 bp in its 5'-untranslated region (5'-UTR). The 3'-flanking regions and 5'-UTR introns in the FAD2-4 and FAD2-3 genes are quite different, indicating that the genes might be paralogs in the cotton genome. Reverse transcriptase (RT)-PCR analysis indicated that the FAD2-4 and FAD2-3 genes were expressed in all tissues examined, including seeds, seedling tissues, young and mature leaves, roots, stems, developing flower buds, and ovule fibers. These constitutive patterns of expression were notably different from that of the FAD2-1 gene, which was restricted to seeds and developing flower buds, or to the expression of a newly-identified FAD2-2 gene isoform, which was barely detectable in roots, hypocotyls, stems, and fibers, but was expressed in all other tissues. The FAD2-4 coding region was expressed in yeast and shown to encode a functional delta-12 desaturase, converting oleic acid (C18:1) to linoleic acid (C18:2) in recombinant yeast cells. In addition, both the FAD2-4 and the FAD2-3 genes were transferred into the Arabidopsis thaliana fad2-1 mutant background where they effectively restored wild type fatty acid composition and growth characteristics. Finally, the cotton FAD2-4 green fluorescent protein (GFP) fusion polypeptide appeared to be localized in the endomembrane system of transgenic Arabidopsis plants in the complemented fad2-1 mutant background, supporting a functional ER location for the cotton FAD2-4 polypeptide in this heterologous plant system. Thus, a new functional member of the FAD2 gene family in cotton has been characterized, indicating a complex regulation of membrane lipid desaturation in this important fiber/oilseed crop.
Assuntos
Arabidopsis/genética , Ácidos Graxos Dessaturases/genética , Expressão Gênica , Genes de Plantas , Gossypium/genética , Saccharomyces cerevisiae/genética , Arabidopsis/enzimologia , DNA de Plantas/genética , Retículo Endoplasmático , Ácidos Graxos Dessaturases/metabolismo , Gossypium/enzimologia , Ácido Linoleico/genética , Ácido Linoleico/metabolismo , Dados de Sequência Molecular , Ácido Oleico/genética , Ácido Oleico/metabolismo , Óleos de Plantas/metabolismo , Estruturas Vegetais/enzimologia , Estruturas Vegetais/genética , Estruturas Vegetais/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Saccharomyces cerevisiae/enzimologia , Transformação GenéticaRESUMO
Periderm is a tissue of secondary origin that replaces damaged epidermis. It can be found in underground plant organs, as an above-ground tissue of woody species (cork), and as a wound-healing tissue. Its outer layers are composed of phellem cells with suberized walls that constitute a protective barrier, preventing pathogen invasion and fluid loss. In potato, a model for periderm studies, periderm tissue replaces the epidermis early in tuber development and the suberized phellems constitute the tuber's skin. To identify factors involved in phellem/skin development and that play a role in its defensive characteristics, two-dimensional gel electrophoresis was used to compare the skin and parenchymatic flesh proteomes of young developing tubers. Proteins exhibiting differentially high signal intensity in the skin were sorted by functional categories. As expected, the differential skin proteome was enriched in proteins whose activity is characteristic of actively dividing tissues such as cell proliferation, C(1) metabolism, and the oxidative respiratory chain. Interestingly, the major functional category consisted of proteins (63%) involved in plant defence responses to biotic and abiotic stresses. This group included three isozymes of caffeoyl-CoA O-methyltransferase and five isozymes of peroxidase that may play a role in suberization processes. The differential expression of these proteins in the skin was further verified by RT-PCR of their corresponding transcripts in skin and tuber flesh samples. The results presented here shed light on the early events in skin development and further expand the concept of the periderm as a protective tissue containing an array of plant defence components.
Assuntos
Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteômica , Solanum tuberosum/genética , Solanum tuberosum/metabolismo , Eletroforese em Gel Bidimensional , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/química , Estruturas Vegetais/química , Estruturas Vegetais/genética , Estruturas Vegetais/metabolismo , Tubérculos/química , Tubérculos/genética , Tubérculos/crescimento & desenvolvimento , Tubérculos/metabolismo , Solanum tuberosum/química , Solanum tuberosum/crescimento & desenvolvimentoRESUMO
The tropical plant Bixa orellana L. (annatto) produces an array of natural products, including the pigment bixin used in the food and cosmetics industries. In order to understand the biochemical and molecular basis of the biosynthesis of these natural products, a reliable method for isolating high yields of high-quality RNA is required. Here we described a successful and reproducible method for isolation and purification of high-quantity and high-quality RNA from different tissues of annatto. This protocol overcomes the usual problems associated with large amounts of polyphenols, polysaccharides, pigments, and other secondary metabolites that are not easily removed by conventional extraction procedures. Furthermore, the proposed protocol can be easily carried out in any laboratory and it could also be extended to isolate RNA from other plant species showing similar abundance of compounds that interfere with RNA extractions. The yield and quality of the RNA were monitored by spectrophotometric analysis, separation on agarose gel, Reverse Transcription-Polymerase Chain Reaction (RT-PCR), and construction of a cDNA library.
Assuntos
Bixaceae/genética , Carotenoides/metabolismo , Flavonoides/metabolismo , Fenóis/metabolismo , Extratos Vegetais/metabolismo , Estruturas Vegetais/química , Polissacarídeos/metabolismo , RNA de Plantas/isolamento & purificação , Bixaceae/química , Bixaceae/metabolismo , Clonagem Molecular , Biblioteca Gênica , Pigmentos Biológicos/metabolismo , Extratos Vegetais/química , Extratos Vegetais/genética , Estruturas Vegetais/genética , Estruturas Vegetais/metabolismo , PolifenóisRESUMO
Maintenance of F-actin turnover is essential for plant cell morphogenesis. Actin-binding protein mutants reveal that plants place emphasis on particular aspects of actin biochemistry distinct from animals and fungi. Here we show that mutants in CAP1, an A. thaliana member of the cyclase-associated protein family, display a phenotype that establishes CAP1 as a fundamental facilitator of actin dynamics over a wide range of plant tissues. Plants homozygous for cap1 alleles show a reduction in stature and morphogenetic disruption of multiple cell types. Pollen grains exhibit reduced germination efficiency, and cap1 pollen tubes and root hairs grow at a decreased rate and to a reduced length. Live cell imaging of growing root hairs reveals actin filament disruption and cytoplasmic disorganisation in the tip growth zone. Mutant cap1 alleles also show synthetic phenotypes when combined with mutants of the Arp2/3 complex pathway, which further suggests a contribution of CAP1 to in planta actin dynamics. In yeast, CAP interacts with adenylate cyclase in a Ras signalling cascade; but plants do not have Ras. Surprisingly, cap1 plants show disruption in plant signalling pathways required for co-ordinated organ expansion suggesting that plant CAP has evolved to attain plant-specific signalling functions.
Assuntos
Citoesqueleto de Actina/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Citoesqueleto de Actina/genética , Actinas/metabolismo , Arabidopsis/citologia , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Citoesqueleto/metabolismo , Morfogênese , Mutação , Estruturas Vegetais/genética , Estruturas Vegetais/crescimento & desenvolvimento , Pólen/fisiologiaRESUMO
Bulb color in onions (Allium cepa) is an important trait whose complex inheritance mechanism involves epistatic interactions among major color-related loci. Recent studies revealed that inactivation of dihydroflavonol 4-reductase (DFR) in the anthocyanin synthesis pathway was responsible for the color differences between yellow and red onions, and two recessive alleles of the anthocyanidin synthase (ANS) gene were responsible for a pink bulb color. Based on mutations in the recessive alleles of these two genes, PCR-based markers for allelic selection were developed. In this study, genotype analysis of onions from segregating populations was carried out using these PCR-based markers. Segregating populations were derived from the cross between yellow and red onions. Five yellow and thirteen pink bulbs from one segregating breeding line were genotyped for the two genes. Four pink bulbs were heterozygous for the DFR gene, which explains the continuous segregation of yellow and pink colors in this line. Most pink onions were homozygous recessive for the ANS gene, except for two heterozygotes. This finding indicated that the homozygous recessive ANS gene was primarily responsible for the pink color in this line. The two pink onions, heterozygous for the ANS gene, were also heterozygous for the DFR gene, which indicated that the pink color was produced by incomplete dominance of a red color gene over that of yellow. One pink line and six other segregating breeding lines were also analyzed. The genotyping results matched perfectly with phenotypic color segregation.
Assuntos
Oxirredutases do Álcool/metabolismo , Cebolas/genética , Oxigenases/metabolismo , Pigmentação/genética , Estruturas Vegetais/fisiologia , Oxirredutases do Álcool/genética , Alelos , Antocianinas/biossíntese , Cruzamento , Genes de Plantas , Genes Recessivos , Marcadores Genéticos , Genótipo , Cebolas/metabolismo , Oxigenases/genética , Pigmentação/fisiologia , Estruturas Vegetais/genéticaRESUMO
Pollen abortion is one of the major reasons causing the inter-subspecific F(1) hybrid sterility in rice and is due to allelic interaction of F(1) pollen sterility genes. The microsporogenesis and microgametogenesis of Taichung 65 and its three F(1) hybrids were comparatively studied by using techniques of differential interference contrast microscopy, semi-thin section light microscopy, epifluorescence microscopy and TEM. The results showed that there were differences among the cytological mechanisms of pollen abortion due to allelic interaction at the three F(1) pollen sterility loci. The allelic interaction at S-a locus resulted in microspores unable to extend the protoplasm membrane with the enlargement of the microspore at the middle microspore stage and finally producing empty abortive pollen. The allelic interaction at S-b locus caused asynchronous development of microspores at the middle microspore stage producing stainable abortive pollen. The allelic interaction at S-c locus mainly led to the non-dissolution of the generative cell wall and finally caused the hybrid F(1) mainly producing stainable abortive pollen. Genotypic identification indicated that the abortive pollen were those with S ( j ) allele.
Assuntos
Alelos , Oryza/genética , Infertilidade das Plantas/genética , Pólen/citologia , Pólen/genética , Cruzamentos Genéticos , Fertilidade/genética , Genótipo , Estruturas Vegetais/genética , Pólen/ultraestruturaRESUMO
We have cloned a ZRT (Zn-regulated transporter), IRT (Fe-regulated transporter)-like protein (ZIP) gene from the strawberry plant (Fragaria x ananassa Duch). This gene, designated as FaZIP1, is composed of three exons and two introns. The locations of the two introns (546 and 157 base pairs) in the gene were confirmed by sequence analysis of cDNA clones obtained by using 3' and 5' RNA ligase mediated-rapid amplification of cDNA ends (RLM-RACE) PCR. Also, based on the cDNA sequence, the transcriptional start site of FaZIP1 was assigned. FaZIP1 is predicted to code for a protein of 353 amino acids containing a signal peptide and eight potential transmembrane domains. Southern blot analysis indicated that FaZIP1 is a member of a multi-gene family. Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis revealed that the FaZIP1 gene is constitutively expressed in strawberry leaves and roots.
Assuntos
Proteínas de Transporte/genética , Fragaria/genética , Genes de Plantas , Sequência de Aminoácidos , Sequência de Bases , Southern Blotting , DNA Complementar/isolamento & purificação , Expressão Gênica , Variação Genética , Dados de Sequência Molecular , Estruturas Vegetais/genética , Rosaceae/genéticaRESUMO
In higher plants, P450s participate in the biosynthesis of many important secondary metabolites. Here we reported for the first time the isolation of a new cytochrome P450 cDNA that expressed in a stem-specific manner from Camptotheca acuminata (designated as CaSS), a native medicinal plant species in China, using RACE-PCR. The full-length cDNA of CaSS was 1735 bp long containing a 1530 bp open reading frame (ORF) encoding a polypeptide of 509 amino acids. Bioinformatic analysis revealed that CASS contained a heme-binding domain PFGXGRRXCX and showed homology to other plant cytochrome P450 monooxygenases and hydroxylases. Southern blotting analysis revealed that there was only one copy of the CaSS present in the genome of Camptotheca acuminata. Northern blotting analysis revealed that CaSS expressed, in a tissuespecific manner, highly in stem and lowly in root, leaf and flower. Our study suggests that CaSS is likely to be involved in the phenylpropanoid pathway.
Assuntos
Camptotheca , Sistema Enzimático do Citocromo P-450/metabolismo , Proteínas de Plantas/metabolismo , Estruturas Vegetais/enzimologia , Sequência de Aminoácidos , Sequência de Bases , Camptotheca/anatomia & histologia , Camptotheca/enzimologia , Camptotheca/genética , Clonagem Molecular , Sistema Enzimático do Citocromo P-450/química , Sistema Enzimático do Citocromo P-450/genética , Modelos Moleculares , Dados de Sequência Molecular , Proteínas de Plantas/química , Proteínas de Plantas/genética , Estruturas Vegetais/genética , Plantas Medicinais/anatomia & histologia , Plantas Medicinais/enzimologia , Plantas Medicinais/genética , Conformação Proteica , Alinhamento de Sequência , Homologia de Sequência de AminoácidosRESUMO
One full length (PrCESA10) and seven other cDNA clones (PrCESA2, 3, 5-8, 11) encoding cellulose synthases (CESAs) were isolated from the coniferous gymnosperm Pinus radiata. PrCESA10 encodes a protein predicted to contain the same domains and regions as angiosperm CESA genes: a zinc finger domain, a hypervariable region 1 (HVR1), a plant-conserved region (CR-P), a class-specific region or hypervariable region 2 (HVR2), in addition to the four conserved domains U1-U4 that are characteristic of the family 2 processive beta-glycosyltransferases. The P. radiata protein is also predicted to contain eight transmembrane domains. The zinc finger domain, the CR-P and the C-terminal portion of the proteins, are highly conserved between P. radiata and the nearest angiosperm CESA protein from Solanum tuberosum. Reverse transcriptase-PCR showed that all the P. radiata genes were expressed in all organs tested, although to different extents. In situ hybridization studies with PrCESA10 in stems of 2- and 12-month-old seedlings showed that it was expressed in the secondary xylem in the two-to-three most recently developed tracheids, which were laying down secondary cell walls.
Assuntos
Celulose/biossíntese , Glucosiltransferases/genética , Pinus/genética , Estruturas Vegetais/genética , Sequência de Aminoácidos , DNA Complementar/química , DNA Complementar/genética , DNA Complementar/isolamento & purificação , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Glucosiltransferases/metabolismo , Hibridização In Situ , Isoenzimas/genética , Isoenzimas/metabolismo , Dados de Sequência Molecular , Filogenia , Pinus/crescimento & desenvolvimento , Pinus/metabolismo , Estruturas Vegetais/crescimento & desenvolvimento , Estruturas Vegetais/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de AminoácidosRESUMO
Little is known about the molecular processes involved in the phloem response to aphid feeding. We investigated molecular responses to aphid feeding on celery (Apium graveolenscv. Dulce) plants infested with the aphid Myzus persicae, as a means of identifying changes in phloem function. We used celery as our model species as it is easy to separate the phloem from the surrounding tissues in the petioles of mature leaves of this species. We generated a total of 1187 expressed sequence tags (ESTs), corresponding to 891 non-redundant genes. We analysed these ESTs in silico after cDNA macroarray hybridisation. Aphid feeding led to significant increase in RNA accumulation for 126 different genes. Different patterns of deregulation were observed, including transitory or stable induction 3 or 7 days after infestation. The genes affected belonged to various functional categories and were induced systemically in the phloem after infestation. In particular, genes involved in cell wall modification, water transport, vitamin biosynthesis, photosynthesis, carbon assimilation and nitrogen and carbon mobilisation were up-regulated in the phloem. Further analysis of the response in the phloem or xylem suggested that a component of the response was developed more specifically in the phloem. However, this component was different from the stress responses in the phloem driven by pathogen infection. Our results indicate that the phloem is actively involved in multiple adjustments, recruiting metabolic pathways and in structural changes far from aphid feeding sites. However, they also suggest that the phloem displays specific mechanisms that may not be induced in other tissues.