The molecular mechanisms by which genes alter development when moved between closely related species

基因在近亲物种之间移动时改变发育的分子机制导致密切相关物种不同的基因分离方法受到以下限制：取决于候选基因的事先鉴定，或者取决于能否使物种杂交，然后分离原因差异。因此，科学家在识别物种差异基因的目标上进展缓慢。该项目正在开发一种新的方法，即转基因基因组学，它利用了基因现在可以在某些植物物种之间轻松转移的特点。该项目测试了阿拉巴马利文沃斯的基因组片段通过转化导入拟南芥的效果。这两个物种有许多明显的差异，但又密切相关。在以前的工作中，已经建立了1200多个拟南芥转基因株系，每个转基因株系都含有随机选择的阿拉巴米卡那DNA片段。对这些进行了目视筛选，以识别持续改变植物形态的DNA片段。对于一些转基因植物与阿拉巴马相似的情况，因果DNA序列将通过测试亚片段来确定是否具有改变植物形态的能力。此外，该项目将尝试完善转基因策略，以便未来的实验能够更有效地进行，目的是最终能够从受体物种的遗传背景中筛选出供体物种的整个基因组，从而识别导致捐赠者和接受者之间差异的基因。这项工作有可能迅速提高我们确定哪些基因导致哪些性状的能力，从而指导有针对性的努力来设计具有理想农艺特征的作物物种。此外，该项目将为本科生、博士后研究员和在科学方面代表性不足的群体中的一名研究生提供培训。

PI: David A. Baum IOS-1021930The molecular mechanisms by which genes alter development when moved between closely related species Available methods for isolating genes that cause closely related species to differ are limited by depending on the prior identification of candidate genes or on being able to hybridize the species and then isolate the causal differences. As a result, scientists are making slow progress towards the aim of identifying species-difference genes. This project is developing a new approach, transgenomics, which exploits the ease with which genes can now be moved between certain plant species. The project tests the effects of genomic fragments from Leavenworthia alabamica when introduced into Arabidopsis thaliana by transformation. These two species have many visible differences, yet are closely related. In prior work, more than 1200 A. thaliana transgenic lines were created that each contain a randomly selected fragment of DNA from L. alabamica. These were visually screened to identify DNA fragments that consistently alter plant form. For some cases where the transgenic plants resemble L. alabamica, the causal DNA sequences will be determined by testing subfragments for an ability to alter plant form. Additionally, the project will attempt to perfect the transgenomic strategy so that future experiments can proceed more efficiently with the aim of ultimately being able to screen an entire genome from a donor species in a recipient species' genetic background so as to identify genes that contributed to the differences between the donor and recipient. This work has the potential to rapidly advance our ability to determine which genes cause which traits and thereby to guide targeted efforts to design crop species with desirable agronomic features. In addition, this project will provide training to undergraduate students, a postdoctoral fellow, and a graduate student from a group underrepresented in science.