Functional characterization of the plant centromeric histone variant CENH3 as a prerequisite to understand kinetochore formation

植物着丝粒组蛋白变体 CENH3 的功能表征是了解着丝粒形成的先决条件

• 批准号: 36126121
• 负责人: Professor Dr. Ingo Schubert
• 金额: --
• 依托单位: Abteilung Züchtungsforschung
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2006
• 资助国家: 德国
• 起止时间: 2005-12-31 至 2009-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/36126121?language=en
• 关键词: Functional; characterization; plant; centromeric; histone

Substitution of histone H3 by the variant CENH3 is a common feature of centromeric nucleosomes of all eukaryotes studied so far. Despite the evolutionary conservation of this process it is unknown what triggers CENH3 deposition and how it becomes targeted to the highly variable centromeric DNA sequences. Such knowledge forms the basis to understand centromere formation and to generate artificial centromeres. The aim of this proposal is to get insight into CENTO deposition in plants by studying consequences of depletion (T-DNA insertion mutants, RNAi) and overexpression of recombinant CENH3 in A. thaliana. Transgenic approaches applying fluorescently tagged CENH3 from species of different phylogenetic affiliation to wild-type and mutant A. thaliana plants should reveal CENH3 functionality across species borders. Reciprocally, the capability of AtCENH3 to target centromeric DNA sequences of other species with different degrees of similarity to A. thaliana centromeric repeats will be tested. Furthermore we will study i) whether in allopolyploids (A. suecica) both parental CENH3 genes are active, ii) the functional requirement of N- and C-terminal parts of CENH3 and iii) the hypotheisis of CENH3 expression during G2 when deposition occurs.

组蛋白H3被变体CENH 3取代是迄今为止研究的所有真核生物的着丝粒核小体的共同特征。尽管这一过程在进化上是保守的，但尚不清楚是什么触发了CENH 3沉积，以及它如何靶向高度可变的着丝粒DNA序列。这些知识形成了理解着丝粒形成和产生人工着丝粒的基础。该提案的目的是通过研究重组CENH 3在A中的缺失（T-DNA插入突变体，RNAi）和过表达的后果来深入了解CENTO在植物中的沉积。thaliana.转基因方法应用荧光标记的CENH 3从物种的不同系统发育从属野生型和突变体A。thaliana植物应该揭示CENH 3跨物种边界的功能。反过来，AtCENH 3靶向与A.将测试拟南芥着丝粒重复。此外，我们将研究i）是否在异源多倍体（A。suecica）两个亲本CENH 3基因都是活性的，ii）CENH 3的N-和C-末端部分的功能要求，和iii）当沉积发生时，CENH 3在G2期间表达的假设。