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诱导多能干细胞新进展 总被引:2,自引:0,他引:2
对近几年来多能干细胞(iPS细胞)的研究进展和安全性问题进行了论述,并对iPS细胞的应用前景进行了展望。 相似文献
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DNA methylation plays an important role in the regulation of gene expression in biotic and abiotic stresses. In the present study, a methylation-sensitive amplified polymorphism (MSAP) analysis was performed to profile DNA methylation changes in seven resistant and sensitive chickpea genotypes following inoculation with Fusarium oxysporum f. sp. ciceris. In all, 27468 DNA fragments, each representing a recognition site cleaved by either or both of two isoschizomers, were amplified using nine selective primer pairs. DNA methylation was evaluated in leaves, stems and roots in control and inoculated plants. Extensive cytosine methylation alterations were found in the pathogen-treated genotypes compared with the corresponding control, including hypermethylation and demethylation as well as the potential conversion of methylation types. For all genotypes, the percentage of demethylated sites were more than methylated sites in infected plants compared with the corresponding control. No significant differences were observed for banding patterns in infected and control leaf tissues, while the differences between percentage of unchanged, methylated and demethylated sites were significant in stem and root tissues. The total numbers of methylated polymorphic bands ranged from 137 to 154 bands in Sel95th1716 and Arman, accounting for 36.81%–44.64% of all bands, respectively. Ten fragments that were differentially amplified between infected and control plants were isolated and sequenced in three tissues separately. Most of sequenced fragments showed homology with disease related genes in GenBank. The results suggest that significant differences in cytosine methylation exist between resistant and sensitive chickpea genotypes, and that hypermethylation or hypomethylation of specific genes may be involved in the chickpea resistance to Fusarium wilt. 相似文献
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谷子杂种优势群的构建方法及研究进展 总被引:1,自引:0,他引:1
根据主要依据地理远缘配制杂交组合、选育杂交种的现状,作者于2007年提出开展"谷子杂种优势群构建、建立杂优利用模式"的构想,并开展了系列研究。目前,已建立了以分子聚类为基础,群体结构分析为主线,数理聚类为辅助,系谱聚类进行验证、校正的类群划分方法,以及双列交试验确定优势类群,建立杂优利用模式的技术路线。并于2009~2010年与美国Kansas State University、USDA-ARS Plant Science and EntomologyResearch Unit Manhattan合作,在国内外率先开展谷子杂种优势群的构建工作,成功地将我国主要谷子育种材料划分为6个类群。目前杂种优势群的构建工作已经完成,杂种优势群的确定和杂优利用模式研究正在进行,预计2011年12月完成。简要介绍了谷子杂种优势群的构建方法及研究进展,以期为谷子杂优利用工作提供一些有益的参考。 相似文献
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