Mutator Transportable Elements of Maize

描述(申请人提供)：转座子产生等位基因多样性 细菌、真菌、植物和动物。传递给后代的新等位基因 提供自然选择作用的多样性，因此转座子是一个 进化的基本机制。此外，在时间尺度上， 单个有机体，转座子可以创造基因表达的多样性 尸体。包括人类在内的哺乳动物免疫球蛋白多样性的产生， 依赖于将抗体基因分割成 几个非功能部分；只有在转座子切除后才有基因 连接在一起的部分形成了一个功能等位基因。加入是一个容易出错的过程 这会产生数百万种产生抗体的等位基因组合。这 等位基因的多样性对我们的生存至关重要，因为我们可以使用小的 动态生成广谱等位基因的遗传基因数量 抵御病原体。这项研究的主要目的是了解 导致不同转位结果的发育转换 含有可遗传等位基因多样性的配子与严格体细胞的比较 在身体里创造的多样性。玉米的MUDR/MU(突变体)转座子 通过在发育很晚的体细胞组织中的“剪切和粘贴”机制 从而在植物体内的精细镶嵌中产生广泛的新等位基因。 这与抗体基因的例子是相似的。相比之下，玉米配子含有 由插入引起的新突变，但没有产生切除等位基因 某一特定基因的多样性。分子和生化机制 对换位中的事件和开关进行高度调节的定时编程 结果将通过分析蛋白质(Mura转座酶和MURB)来阐明 辅助蛋白)由调节转座子MuDR编码。主控因素 调节MuDR/Mu活性也将具有特征性，因为转座 元素活性是反式Doson及其宿主的进化产物。

DESCRIPTION (provided by applicant): Transposons generate allelic diversity in bacteria, fungi, plants, and animals. New alleles transmitted to progeny provide diversity upon which natural selection acts, hence transposons are one of the underlying mechanisms of evolution. In addition, on the time scale of a single organism, transposons can create diversity of gene expression within the body. The generation of immunoglobin diversity in mammals, including humans, depends on the excision of transposons that divide the antibody genes into several non-functional parts; only after transposon excisions are the gene parts joined to make a functional allele. Joining is an error-prone process that generates millions of combinations of antibody-producing alleles. This diversity of alleles is crucial to our survival,-because we can use a small number of inherited genes to dynamically generate a wide spectrum of alleles to defend against pathogens. The principal aim of this study is to understand a developmental switch that results in a different transpositional outcome in gametes containing heritable allelic diversity compared to strictly somatic diversity created in the body. The MuDR/Mu (Mutator) transposons of maize move by a "cut and paste" mechanism in somatic tissues, very late in development resulting in a wide spectrum of new alleles in a fine mosaic in the plant body. This parallels the antibody gene example. In contrast, maize gametes contain new mutations caused by insertion but no excision alleles that generate diversity in a particular gene. The molecular and biochemical mechanisms programming the highly regulated timing of events and switch in transpositional outcome will be elucidated by analyzing proteins (MURA transposases and MURB helper proteins) encoded by the regulatory transposon MuDR. Host factors that regulate MuDR/Mu activities will also be characterized, because transposable element activities are an evolved nartnershiD of the transDoson and its host.