BEHAVIOR OF P FACTORS MOVABLE ELEMENTS IN DROSOPHILA

P 因子在果蝇中的可动元件的行为

• 批准号: 3278833
• 负责人: William R. ENGELS
• 金额: $ 19.62万
• 依托单位: UNIVERSITY OF WISCONSIN-MADISON
• 依托单位国家: 美国
• 财政年份: 1982
• 资助国家: 美国
• 起止时间: 1982-07-01 至 1990-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3278833
• 关键词: chromosome aberrations; chromosome disorders; developmental genetics; endonuclease; fertility; gene expression; gene frequency; genetic manipulation; genetic recombination; genotype; germ cells; molecular cloning; molecular genetics; population genetics; sex chromosomes; transposon /insertion element

Transposable elements are now thought to be common in higher organisms, and might contribute substantially to the mutation rate. Similarities in structure and behavior have been established between retroviruses and some transposable elements. Understanding the role of these elements in the biology of higher organisms is the long term objective of this research. The present focus is on a family of transposable elements in D. melanogaster known as P factors. Under certain conditions, P factors cause a syndrome of high mutability and other germline abberations known collectively as hybrid dysgenesis. The proposed experiments are aimed at determining the behavior of P elements in terms of their (a) transposition, (b) excision, and (c) regulation. Special attention will be given to the roles of these processes in the ability of P factors to invade populations. The data will also have applications for using P elements as tools in other studies of the molecular genetics of Drosophila. We approach these problems with a balanced combination of molecular and classical genetic techniques. (a) Transposition: Using in situ hybridization and other standard recombinant DNA techniques, we will follow the course of events when P factors are introduced into a genome. The phenomena of transpositional "explosions" and inter-specific invasion of P elements will also be investigated in this experiment. The insertional site specificity of P elements will be analyzed by placing a short (1000 base pairs) insertional preference region from the singed gene into a the alcohol dehydrogenase gene where P elements do not otherwise insert. (b) Excision: We will collect a large number of P element excisions and determine the spectrum of events (partial, complete, flanking, etc.) that occur. By looking for changes from small to large elements we will test the hypothesis that P elements undergo frequent gene conversion as opposed to simple excision. A continuing long term experiment will determine whether excision can result in the loss of P elements from laboratory strains. (c) Regulation: P element activity is closely regulated by tissue specificity and cytotype. We will use a hypermutable double P element insertion in the singed bristle gene and a collection of in vitro modified P elements to analyze the components in these regulation systems. The role of regulation in limiting the spread of P elements in a population will also be determined by using in situ hybridization to follow the invasion process while monitoring for suppression of transpositional activity.

现在认为转座元素在更高的生物体中很常见，并且 可能会大大促进突变率。 相似之处 逆转录病毒与某些逆转录病毒之间已经建立了结构和行为 转座元素。 了解这些元素在 较高生物体的生物学是这项研究的长期目标。 目前的重点是D。 Melanogaster被称为P因素。 在某些条件下，P因素导致 高可突变性和其他种系差的综合征已知 统称为杂种失调。 提出的实验旨在确定P的行为 根据其（a）换位，（b）切除和（c）的元素 规定。 将特别注意这些角色 P因素入侵人群的能力的过程。 数据将 在其他研究中，还具有将P元素用作工具的应用 果蝇的分子遗传学。 我们通过 分子和经典遗传技术的平衡组合。 （a）换位：使用原位杂交和其他标准 重组DNA技术，我们将遵循p时事件的过程 因素被引入基因组。 转置现象 P元素的“爆炸”和特异性入侵也将是 在此实验中进行了研究。 P的插入位点特异性 将通过放置短（1000个碱基对）插入来分析元素 从唱基因到酒精脱氢酶的优先区域 p元素不插入的基因。 （b）切除：我们将收集大量的P元素切除和 确定事件的范围（部分，完整，侧翼等） 发生。 通过寻找从小到大元素的变化，我们将测试 P元素经常进行基因转化而相反的假设 简单切除。 持续的长期实验将决定 切除是否会导致实验室失去P元素 菌株。 （c）调节：P元素活性受组织密切调节 特异性和细胞型。 我们将使用超重的双P元素 插入唱歌的猪毛基因和一系列体外修饰的集合 P要素分析这些调节系统中的组件。 角色 限制P元素在人群中的传播的监管将 也可以通过使用原位杂交遵循入侵来确定 在监测抑制座位活性的同时。