共查询到20条相似文献,搜索用时 31 毫秒
1.
S. Y. Park H. N. Murthy D. Chakrabarthy K. Y. Paek 《In vitro cellular & developmental biology. Plant》2009,45(1):104-108
Somaclones exhibiting variations with flower characteristics were recovered from the tissue-culture-derived plants of Doritaenopsis. Two molecular techniques, random amplified polymorphic DNA (RAPD) and methylation-sensitive amplification polymorphism (MSAP)
analyses, were used to characterize the somaclones. RAPD analysis, using 100 randomly selected primers, failed to differentiate
variants and normal plants, even though some primers (six out of 100 primers) exhibited 6–10 distinct banding patterns. However,
MSAP analysis revealed the differences in the DNA methylation patterns in the normal and variant plants which were correlated
with phenotypic variation. In all, 311, 337, 366, and 343 fragments were obtained with normal and V1, V2, and V3 variant plants,
respectively; each representing recognition site cleaved by either or both of the isoshizomers were amplified using 12 combination
of primers. A total of 36 (11.6%), 77 (22.9%), 73 (19.9%), and 47 (13.7%) sites were found to be methylated at cytosine in
the genomes of normal and V1, V2, and V3 variant Doritaenopsis plants. This study demonstrates usefulness of MSAP to detect DNA methylation events in tissue cultured Doritaenopsis plants. 相似文献
2.
Background
Floral traits within plants can vary with flower position or flowering time. Within an inflorescence, sexual allocation of early produced basal flowers is often female-biased while later produced distal flowers are male-biased. Such temporal adjustment of floral resource has been considered one of the potential advantages of modularity (regarding a flower as a module) in hermaphrodites. However, flowers are under constraints of independent evolution of a given trait. To understand flower diversification within inflorescences, here we examine variation and covariation in floral traits within racemes at the individual and the maternal family level respectively in an alpine herb Aconitum gymnandrum (Ranunculaceae). 相似文献3.
Background
Azalea (Rhododendron simsii hybrids) is the most important flowering pot plant produced in Belgium, being exported world-wide. In the breeding program, flower color is the main feature for selection, only in later stages cultivation related plant quality traits are evaluated. As a result, plants with attractive flowering are kept too long in the breeding cycle. The inheritance of flower color has been well studied; information on the heritability of cultivation related quality traits is lacking. For this purpose, QTL mapping in diverse genetic backgrounds appeared to be a must and therefore 4 mapping populations were made and analyzed. 相似文献4.
Premise
Intersexual mating facilitation in flowering plants has been largely underexplored. Duodichogamy is a rare flowering system in which individual plants flower in the sequence male-female-male. We studied the adaptive advantages of this flowering system using chestnuts (Castanea spp., Fagaceae) as models. These insect-pollinated trees produce many unisexual male catkins responsible for a first staminate phase and a few bisexual catkins responsible for a second staminate phase. We hypothesized that duodichogamy increases female mating success by facilitating pollen deposition on stigmas of the rewardless female flowers through their proximity with attractive male flowers responsible for the minor staminate phase.Methods
We monitored insect visits to 11 chestnut trees during the entire flowering period and explored reproductive traits of all known duodichogamous species using published evidence.Results
In chestnuts, insects visited trees more frequently during the first staminate phase but visited female flowers more frequently during the second staminate phase. All 21 animal-pollinated duodichogamous species identified are mass-flowering woody plants at high risk of self-pollination. In 20 of 21 cases, gynoecia (female flower parts) are located close to androecia (male flower parts), typically those responsible for the second minor staminate phase, whereas androecia are often distant from gynoecia.Conclusions
Our results suggest that duodichogamy increases female mating success by facilitating pollen deposition on stigmas by means of the attractiveness of the associated male flowers while effectively limiting self-pollination.5.
Background
Whole genome sequencing of bisulfite converted DNA (‘methylC-seq’) method provides comprehensive information of DNA methylation. An important application of these whole genome methylation maps is classifying each position as a methylated versus non-methylated nucleotide. A widely used current method for this purpose, the so-called binomial method, is intuitive and straightforward, but lacks power when the sequence coverage and the genome-wide methylation level are low. These problems present a particular challenge when analyzing sparsely methylated genomes, such as those of many invertebrates and plants.Results
We demonstrate that the number of sequence reads per position from methylC-seq data displays a large variance and can be modeled as a shifted negative binomial distribution. We also show that DNA methylation levels of adjacent CpG sites are correlated, and this similarity in local DNA methylation levels extends several kilobases. Taking these observations into account, we propose a new method based on Bayesian classification to infer DNA methylation status while considering the neighborhood DNA methylation levels of a specific site. We show that our approach has higher sensitivity and better classification performance than the binomial method via multiple analyses, including computational simulations, Area Under Curve (AUC) analyses, and improved consistencies across biological replicates. This method is especially advantageous in the analyses of sparsely methylated genomes with low coverage.Conclusions
Our method improves the existing binomial method for binary methylation calls by utilizing a posterior odds framework and incorporating local methylation information. This method should be widely applicable to the analyses of methylC-seq data from diverse sparsely methylated genomes. Bis-Class and example data are provided at a dedicated website (http://bibs.snu.ac.kr/software/Bisclass).Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-608) contains supplementary material, which is available to authorized users. 相似文献6.
Whole‐genome DNA methylation patterns and complex associations with gene structure and expression during flower development in Arabidopsis
下载免费PDF全文
![点击此处可从《The Plant journal : for cell and molecular biology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Hongxing Yang Fang Chang Chenjiang You Jie Cui Genfeng Zhu Lei Wang Yu Zheng Ji Qi Hong Ma 《The Plant journal : for cell and molecular biology》2015,81(2):268-281
7.
Weiguo Han Tao Wang Andrew A Reilly Steven M Keller Simon D Spivack 《Respiratory research》2009,10(1):86
Background
There is a need for new, noninvasive risk assessment tools for use in lung cancer population screening and prevention programs.Methods
To investigate the technical feasibility of determining DNA methylation in exhaled breath condensate, we applied our previously-developed method for tag-adapted bisulfite genomic DNA sequencing (tBGS) for mapping of DNA methylation, and adapted it to exhaled breath condensate (EBC) from lung cancer cases and non-cancer controls. Promoter methylation patterns were analyzed in DAPK, RASSF1A and PAX5β promoters in EBC samples from 54 individuals, comprised of 37 controls [current- (n = 19), former- (n = 10), and never-smokers (n = 8)] and 17 lung cancer cases [current- (n = 5), former- (n = 11), and never-smokers (n = 1)].Results
We found: (1) Wide inter-individual variability in methylation density and spatial distribution for DAPK, PAX5β and RASSF1A. (2) Methylation patterns from paired exhaled breath condensate and mouth rinse specimens were completely divergent. (3) For smoking status, the methylation density of RASSF1A was statistically different (p = 0.0285); pair-wise comparisons showed that the former smokers had higher methylation density versus never smokers and current smokers (p = 0.019 and p = 0.031). For DAPK and PAX5β, there was no such significant smoking-related difference. Underlying lung disease did not impact on methylation density for this geneset. (4) In case-control comparisons, CpG at -63 of DAPK promoter and +52 of PAX5β promoter were significantly associated with lung cancer status (p = 0.0042 and 0.0093, respectively). After adjusting for multiple testing, both loci were of borderline significance (padj = 0.054 and 0.031). (5) The DAPK gene had a regional methylation pattern with two blocks (1)~-215~-113 and (2) -84 ~+26); while similar in block 1, there was a significant case-control difference in methylation density in block 2 (p = 0.045); (6)Tumor stage and histology did not impact on the methylation density among the cases. (7) The results of qMSP applied to EBC correlated with the corresponding tBGS sequencing map loci.Conclusion
Our results show that DNA methylation in exhaled breath condensate is detectable and is likely of lung origin. Suggestive correlations with smoking and lung cancer case-control status depend on individual gene and CpG site examined. 相似文献8.
Lessi F Beggs A de Palo M Anti M Macarone Palmieri R Francesconi S Gomes V Bevilacqua G Tomlinson I Segditsas S 《PloS one》2010,5(11):e13840
Background
We have previously shown that serum/glucocorticoid regulated kinase 1 (SGK1) is down-regulated in colorectal cancers (CRC) with respect to normal tissue. As hyper-methylation of promoter regions is a well-known mechanism of gene silencing in cancer, we tested whether the SGK1 promoter region was methylated in colonic tumour samples.Methodology/Principal Findings
We investigated the methylation profile of the two CpG islands present in the promoter region of SGK1 in a panel of 5 colorectal cancer cell lines by sequencing clones of bisulphite-treated DNA samples. We further confirmed our findings in a panel of 10 normal and 10 tumour colonic tissue samples of human origin. We observed CpG methylation only in the smaller and more distal CpG island in the promoter region of SGK1 in both normal and tumour samples of colonic origin. We further identified a single nucleotide polymorphism (SNP, rs1743963) which affects methylation of the corresponding CpG.Conclusions/Significance
Our results show that even though partial methylation of the promoter region of SGK1 is present, this does not account for the different expression levels seen between normal and tumour tissue. 相似文献9.
Inhibition of SAH-hydrolase activity during seed germination leads to deregulation of flowering genes and altered flower morphology in tobacco 总被引:1,自引:0,他引:1
Fulneček J Matyášek R Votruba I Holý A Křížová K Kovařík A 《Molecular genetics and genomics : MGG》2011,285(3):225-236
Developmental processes are closely connected to certain states of epigenetic information which, among others, rely on methylation
of chromatin. S-adenosylmethionine (SAM) and S-adenosylhomocysteine (SAH) are key cofactors of enzymes catalyzing DNA and histone methylation. To study the consequences
of altered SAH/SAM levels on plant development we applied 9-(S)-(2,3-dihydroxypropyl)-adenine (DHPA), an inhibitor of SAH-hydrolase, on tobacco seeds during a short phase of germination
period (6 days). The transient drug treatment induced: (1) dosage-dependent global DNA hypomethylation mitotically transmitted
to adult plants; (2) pleiotropic developmental defects including decreased apical dominance, altered leaf and flower symmetry,
flower whorl malformations and reduced fertility; (3) dramatic upregulation of floral organ identity genes NTDEF, NTGLO and NAG1 in leaves. We conclude that temporal SAH-hydrolase inhibition deregulated floral genes expression probably via chromatin
methylation changes. The data further show that plants might be particularly sensitive to accurate setting of SAH/SAM levels
during critical developmental periods. 相似文献
10.
Background
DNA-dependent RNA polymerase IV and V (Pol IV and V) are multi-subunit enzymes occurring in plants. The origin of Pol V, specific to angiosperms, from Pol IV, which is present in all land plants, is linked to the duplication of the gene encoding the largest subunit and the subsequent subneofunctionalization of the two paralogs (NRPD1 and NRPE1). Additional duplication of the second-largest subunit, NRPD2/NRPE2, has happened independently in at least some eudicot lineages, but its paralogs are often subject to concerted evolution and gene death and little is known about their evolution nor their affinity with Pol IV and Pol V. 相似文献11.
Artemisinin is a promising and potent antimalarial drug naturally produced by the plant Artemisia annua L. but in very low yield. Its artemisinin content is known to be greatly affected by both genotype and environmental factors.
In this study, the production of artemisinin and leaf biomass in Artemisia annua L. was significantly increased by exogenous GA3 treatment. The effect of GA3 application on expression of proposed key enzymes involved in artemisinin yield was examined in both wild type (007) and
FPS-overexpression (253-2) lines of A. annua. In the wild type (007) at 6 h post GA3 application there was an abrupt rise in FPS, ADS and CYP71AV1 expression and at 24 h a temporary and significant peak in artemisinin (1.45-fold higher than the control). After GA3 application in line 253-2, there was a dramatic rise in expression of FPS at 3 h, CYP71AV1 at 9 h and ADS at 72 h and accumulation of artemisinin after 7 days, which was a delay when compared with the wild type plant. Thus, increased
artemisinin content from exogenous GA3 treatment was associated with increased expression of key enzymes in the artemisinin biosynthesis pathway. Interestingly,
exogenous GA3 continuously enhanced artemisinin content from the vegetative stage to flower initiation in both plant lines and gave significantly
higher leaf biomass than in control plants. Consequently, the artemisinin yield in GA3-treated plants was much higher than in control plants. Although the maximum artemisinin content was found at the full blooming
stage [2.1% dry weight (DW) in 007 and 2.4% DW in 253-2], the highest artemisinin yield in GA3-treated plants was obtained during the flower initiation stage (2.4 mg/plant in 007 and 2.3 mg/plant in 235-2). This was
26.3 and 27.8% higher, respectively, than in non-treated plants 007 and 253-2. This study showed that exogenous GA3 treatment enhanced artemisinin production in pot experiments and should be suitable for field application. 相似文献
12.
Background
Methyl-DNA binding proteins help to translate epigenetic information encoded by DNA methylation into covalent histone modifications. MBD2/3 is the only candidate gene in the Drosophila genome with extended homologies to mammalian MBD2 and MBD3 proteins, which represent a co-repressor and an integral component of the Nucleosome Remodelling and Deacetylase (NuRD) complex, respectively. An association of Drosophila MBD2/3 with the Drosophila NuRD complex has been suggested previously. We have now analyzed the molecular interactions between MBD2/3 and the NuRD complex in greater detail. 相似文献13.
Frédéric Ngezahayo Chunming Xu Hongyan Wang Lily Jiang Jinsong Pang Bao Liu 《BMC plant biology》2009,9(1):91
Background
mPing is an endogenous MITE in the rice genome, which is quiescent under normal conditions but can be induced towards mobilization under various stresses. The cellular mechanism responsible for modulating the activity of mPing remains unknown. Cytosine methylation is a major epigenetic modification in most eukaryotes, and the primary function of which is to serve as a genome defense system including taming activity of transposable elements (TEs). Given that tissue-culture is capable of inducing both methylation alteration and mPing transposition in certain rice genotypes, it provides a tractable system to investigate the possible relationship between the two phenomena. 相似文献14.
Camilo Salazar Chris D Jiggins Jesse E Taylor Marcus R Kronforst Mauricio Linares 《BMC evolutionary biology》2008,8(1):132
Background
The neotropical butterfly Heliconius heurippa has a hybrid colour pattern, which also contributes to reproductive isolation, making it a likely example of hybrid speciation. Here we used phylogenetic and coalescent-based analyses of multilocus sequence data to investigate the origin of H. heurippa. 相似文献15.
Premise
Characterizing the developmental processes in the transition from hermaphroditism to unisexuality is crucial for understanding floral evolution. Amaranthus palmeri, one of the most devastating weeds in the United States, is an emerging model system for studying a dioecious breeding system and understanding the biological traits of this invasive weed. The objectives of this study were to characterize phases of flower development in A. palmeri and compare organogenesis of flower development in female and male plants.Methods
Flower buds from male and female plants were dissected for light microscopy. Segments of male and female inflorescences at different stages of development were cut longitudinally and visualized using scanning electron microscopy.Results
Pistillate flowers have two to three styles, one ovary with one ovule, and five obtuse tepals. Staminate flowers have five stamens with five acute tepals. Floral development was classified into 10 stages. The distinction between the two flower types became apparent at stage four by the formation of stamen primordia in staminate flowers, which developed female and male reproductive organs initially, as contrasted to pistillate flowers, which produced carpel primordia only. In staminate flowers, the putative carpel primordia changed little in size and remained undeveloped.Conclusions
Timing of inappropriate organ termination varies across the two sexes in A. palmeri. Our study suggests that the evolution of A. palmeri from a cosexual ancestral state to complete dioecy is still in progress since males exhibited transient hermaphroditism and females produced strictly pistillate flowers. 相似文献16.
Diana Lucifero Sophie La Salle Déborah Bourc'his Josée Martel Timothy H Bestor Jacquetta M Trasler 《BMC developmental biology》2007,7(1):36
Background
Normal mammalian development requires the action of DNA methyltransferases (DNMTs) for the establishment and maintenance of DNA methylation within repeat elements and imprinted genes. Here we report the expression dynamics of Dnmt3a and Dnmt3b, as well as a regulator of DNA methylation, Dnmt3L, in isolated female germ cells. 相似文献17.
Katriina Mouhu Timo Hytönen Kevin Folta Marja Rantanen Lars Paulin Petri Auvinen Paula Elomaa 《BMC plant biology》2009,9(1):122-16
Background
We are studying the regulation of flowering in perennial plants by using diploid wild strawberry (Fragaria vesca L.) as a model. Wild strawberry is a facultative short-day plant with an obligatory short-day requirement at temperatures above 15°C. At lower temperatures, however, flowering induction occurs irrespective of photoperiod. In addition to short-day genotypes, everbearing forms of wild strawberry are known. In 'Baron Solemacher' recessive alleles of an unknown repressor, SEASONAL FLOWERING LOCUS (SFL), are responsible for continuous flowering habit. Although flower induction has a central effect on the cropping potential, the molecular control of flowering in strawberries has not been studied and the genetic flowering pathways are still poorly understood. The comparison of everbearing and short-day genotypes of wild strawberry could facilitate our understanding of fundamental molecular mechanisms regulating perennial growth cycle in plants. 相似文献18.
19.