Characterization and Role of SAR Elements Flanking the HSC80Locus of Tomato

番茄 HSC80 基因座两侧 SAR 元件的特征和作用

• 批准号: 9205573
• 负责人: Luca Comai
• 金额: $ 19.01万
• 依托单位: University of Washington
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-09-15 至 1995-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9205573&HistoricalAwards=false
• 关键词: Characterization; Role; SAR; Elements; Flanking

The relationship between chromatin organization, nuclear architecture and gene expression in all eukaryotes and, specifically, in terrestrial plants is a complex and unresolved question. Chromosomal domains, consisting of chromatin loops attached to the chromosomal scaffold, may provide a specialized environment for gene expression. Supporting this hypothesis, transgenes inserted at different loci in a plant genome very in expression levels. Scaffold Attachment Regions (SAR) are DNA elements that bind to the nuclear scaffolds and could anchor loop domains. We have discovered that the HSC80 gene of tomato is flanked by SAR regions, suggesting that, in vivo, the association of these SAR elements with the scaffold. The putative loop domain will be compared to a DNAase I-hypersensitivity map of the same region. Using transgenic plants, we will determine whether flanking SARs are necessary for position-independent, copy-number- dependent expression of a HSC80-Gus chimeric gene and of a mannopine synthase (Mas)-Gus chimeric gene. To avoid a selection bias, we will characterize the expression pattern of Mas-Gus transgenes that were not directly selected. We will obtain unselected insertion of the chimeric Gus gene by co-transformation with a separate T-DNA carrying the kanamycin resistance gene. %%% It has been clear for some time that the programmed regulation of gene expression during development and in different tissues is too complex to be totally explained by cis and trans acting factors. One idea which has become more and more acceptable is that chromosome structure somehow plays a part in such precise control of gene expression and the information which should result from the successful completion of this work will give greater insight into possible mechanisms of regulation.

染色质组织、细胞核 所有真核生物的结构和基因表达， 特别是在陆生植物中， 问题 染色体结构域，由染色质环组成 附着在染色体支架上，可以提供一个专门的 基因表达的环境。 支持这一假设， 在植物基因组的不同位点插入的转基因， 表达水平。 支架附着区（SAR）是DNA 与核支架结合并能锚环的元件 域. 我们已经发现番茄的HSC 80基因是 两侧是SAR区域，这表明，在体内， 这些SAR元件的支架。 推定的环结构域 将与相同的DNA酶I-超敏反应图谱进行比较。 地区 利用转基因植物，我们将确定 侧翼SAR是位置独立的，拷贝数， HSC 80-Gus嵌合基因的依赖性表达和HSC 80-Gus嵌合基因的依赖性表达， 甘露碱合酶（Mas）-Gus嵌合基因。 避免选择 偏见，我们将描述Mas-Gus的表达模式 不是直接选择的转基因。 我们将获得 通过共转化的嵌合Gus基因的快速插入 带有卡那霉素抗性基因的T-DNA %%% 一段时间以来，很明显， 在发育过程中和不同组织中的基因表达也是 复杂的顺式和反式作用因子完全解释。 一个越来越被人们接受的观点是， 染色体结构在这种精确控制中起着某种作用 基因表达和信息应该产生于 这项工作的成功完成将使我们更深入地了解 可能的监管机制。