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DNA甲基化在植物研究中的应用现状与前景 总被引:2,自引:0,他引:2
DNA甲基化是主要发生在CpG双核苷酸序列中的胞嘧啶上的一种表面遗传修饰。它以S-腺苷甲硫氨酸为甲基供体,在DNA甲基酶的催化下,将甲基转移到胞嘧啶上,生成5-甲基胞嘧啶。DNA甲基化在植物的很多生命过程中具有重要的作用。本文就其作用机制、主要研究应用以及未来的前景进行简单阐述,从而为DNA甲基化在植物遗传学研究中的研究提供理论参考。 相似文献
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植物表观遗传与DNA甲基化 总被引:1,自引:0,他引:1
表观遗传在植物生长发育过程中起着极其重要的作用。甲基化是基因组DNA的一种主要表观遗传修饰形式,是调节基因功能的重要手段。介绍了植物体中胞嘧啶甲基化现象,RNA指导的DNA甲基化的信号分子、作用机制,以及与RNA介导的基因沉默机制之间的区别和RNA对转座子的表观控制。 相似文献
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DNA甲基化是主要发生在CpG双核苷酸序列中胞嘧啶上的一种表面遗传修饰.它以S-腺苷甲硫氨酸为甲基供体,在DNA甲基酶的催化下,将甲基转移到胞嘧啶上,生成5-甲基胞嘧啶.DNA甲基化在植物的很多生命过程中具有重要的作用.本文就其作用机制、主要研究应用以及未来的前景进行综述,从而为DNA甲基化在植物遗传学中的研究提供理论参考. 相似文献
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DNA甲基化与植物的生长发育 总被引:13,自引:0,他引:13
文章就DNA甲基化与植物生长发育的关系、催化甲基化的酶、5-甲基胞嘧啶在植物基因组中的分布、甲基化的发生和遗传的研究进展作了介绍。 相似文献
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R. Cremonini M. Ruffini Castiglione V.G. Grif V.V. Kotseruba E.O. Punina A.V. Rodionov O.V. Muravenko K.V. Popov T.E. Samatadze A.V. Zelenin 《Biologia Plantarum》2003,46(4):543-550
Chromosome structure and chromatin organisation of a two-chromosome model cereal Zingeria biebersteiniana (Claus) P. Smirnov were studied: nuclear DNA content was determined by microdensitometric analysis after Feulgen staining;
Feulgen absorption at different thresholds of absorbance in interphase nuclei also provided evidence on the organisation of
chromatin, allowing quantitative estimation of condensed chromatin within interphasic nucleus. The DNA methylation pattern
of Z. biebersteiniana metaphase chromosomes was examined with a specific monoclonal antibody. 5-methyl-cytosine residues are present in several
chromosome sites and differences may be present between corresponding regions of homologues. Chromosome banding pattern reveals
large bands in the centromeric regions of each chromosome, showing constitutive heterochromatin; by fluorochromes staining
pericentromeric blocks are evidenced. After the cold and 9-aminoacridine pre-treatments and after aceto-carmine and aceto-orceine
staining, respectively, the metaphase chromosomes were analysed by image analysis system revealing a segmentation of the chromosome
body that resembles Giemsa/Reverse banding in animal chromosomes.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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植物离体培养过程中DNA甲基化变异研究进展 总被引:1,自引:0,他引:1
表现遗传变异对于植物的生长发育起着重要作用,主要包括DNA甲基化、组蛋白修饰、染色体重塑和RNA干涉等.DNA甲基化是一种最重要的表现遗传机制,在植物离体培养过程中广泛存在,本文对植物离体培养过程的DNA甲基化变异现象、影响因素及机理等情况进行综述. 相似文献
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Shay Shilo Cathy Melamed-Bessudo Yanniv Dorone Naama Barkai Avraham A. Levy 《The Plant cell》2015,27(9):2427-2436
The rate of crossover, the reciprocal exchanges of homologous chromosomal segments, is not uniform along chromosomes differing between male and female meiocytes. To better understand the factors regulating this variable landscape, we performed a detailed genetic and epigenetic analysis of 737 crossover events in Arabidopsis thaliana. Crossovers were more frequent than expected in promoters. Three DNA motifs enriched in crossover regions and less abundant in crossover-poor pericentric regions were identified. One of these motifs, the CCN repeat, was previously unknown in plants. The A-rich motif was preferentially associated with promoters, while the CCN repeat and the CTT repeat motifs were preferentially associated with genes. Analysis of epigenetic modifications around the motifs showed, in most cases, a specific epigenetic architecture. For example, we show that there is a peak of nucleosome occupancy and of H3K4me3 around the CCN and CTT repeat motifs while nucleosome occupancy was lowest around the A-rich motif. Cytosine methylation levels showed a gradual decrease within ∼2 kb of the three motifs, being lowest at sites where crossover occurred. This landscape was conserved in the decreased DNA methylation1 mutant. In summary, the crossover motifs are associated with epigenetic landscapes corresponding to open chromatin and contributing to the nonuniformity of crossovers in Arabidopsis. 相似文献
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胁迫是指生物体持续地暴露在环境的刺激下,并且植物有能力建立保护和适应的机制.逆境胁迫抑制生物体的生长、发育和繁殖,它通常决定了物种的分布,更重要的是它对特定的种群提供了一种选择性进化动力.植物可以通过忍受、抗性和避免或最终逃避这三种不同的策略来应对胁迫.DNA甲基化作为一种表观遗传现象,是指在甲基化酶的作用下,不涉及基因的DNA序列改变,而使基因功能发生变化,以对外界的环境刺激作出应答反应.这种变化常常可以传递给后代,并形成表观遗传记忆,这对培育植物抗性新品种提供了可能.综述了植物响应逆境胁迫中的DNA甲基化修饰的研究进展,旨在深入了解DNA甲基化变化对植物抗逆性的影响. 相似文献
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