Molecular and Genetic Studies on Maize Elements

玉米中Ac转座因子的功能是 由它自己的产物转座酶控制， 反式激活蛋白导致稳态条件。 Ac的活化与 启动子区 结构改变，有缺陷的Ac元件 不同之处在于它们的启动子的去甲基化， 转座酶将用于一项旨在确定 启动子去甲基化的分子基础 第二 该项目的一部分涉及对远程独联体的分析 Ac-Ds系统的元素之间的相互作用。 当Ac 和Ds元件偶联在相同的染色体臂上， 末端元件被甲基化，并且不被 甲基化酶敏感性限制酶。 这种效果是 仅限于在同一染色体臂上偶联的元件，但 它们可以相距50个地图单位。 许多不同的双 Ac、Ds和其他标记基因的三重组合将 来研究这种远程CIS的性质 互动 在以前的NSF支持期间，本文的作者 一项研究发现，一个基因可以影响 同一染色体上的另一个基因的行为 比以前想象的更远。 他现在提议 继续这一发现，并试图阐明 这种基因间的长距离相互作用 发生.

The functioning of the Ac transposable element in maize is controlled by its own product, transposase, that acts as a transactivating protein resulting in a steady state condition. Activation of Ac is associated with the demethylation of the promoter region. Structurally altered, defective Ac elements that differ in the demethylation of their promoter by transposase will be employed in a study designed to determine the molecular basis for the promoter demethylation. The second part of this project involves an analysis of the long range cis interaction between elements of the Ac-Ds system. When an Ac and a Ds element are coupled on the same chromosome arms, the distal element becomes methylated and is not digested by methylase-sensitive restriction enzymes. This effect is limited to elements coupled on the same chromosome arm, but they may be as far apart as 50 map units. Many different double and triple combinations of Ac, Ds and other marker genes will be constructed to study the nature of this long range cis interaction. During a period of previous NSF support, the author of this proposal has discovered that one gene can influence the behavior of another gene on the same, chromosome over much greater distances than previously imagined. He now proposes to pursue this discovery, and attempt to elucidate the mechanism by which such long-range interactions among genes occur.