Rapid and Targeted Introgression of Traits via Genome Elimination

主要研究者：Luca Comai（加州大学戴维斯分校）：Ek Han Tan（加州大学戴维斯分校）; Anne布里特（加州大学戴维斯分校）; Awais Khan（国际马铃薯中心，秘鲁）;合作者：Ravi Maruthachalam（印度IISER-TVM）; Meredith Bonierbale（国际马铃薯中心，秘鲁）一个常见的植物育种程序涉及将有价值的性状（如抗病性）从野生亲缘植物转移到作物品种。为了实现这一目标，育种者将野生品种与作物品种杂交。 其结果被称为杂种，它混合了父母双方的基因。然而，野生品种的大多数基因不适合农业，必须被抛弃。这是通过与作物品种反复杂交，再加上对感兴趣的性状的选择来实现的，这一过程称为回交，通常需要长达10年的时间。这对开发新品种构成了严重的瓶颈。 因此，当人类的生计依赖于新的改良品种的快速开发时，在面临意想不到的作物挑战时，缩短开发时间尤为关键。该项目满足了这一需求。以马铃薯为实验材料，研究了一种快速将有用性状导入作物的方法。加州大学戴维斯分校和国际马铃薯中心之间的合作还将对研究生和本科生进行基于基因组的育种培训。 这种方法将适用于许多作物品种，对基础研究和应用研究都很有用。单倍体诱导是一种产生具有单一基因组而不是两个亲本基因组的植物的过程，可以大大缩短培育新品种所需的时间。然而，没有任何方法解决了克服连锁阻力的问题，连锁阻力是有害基因与理想基因之间常见的负相关。该项目团队发现了一种方法，可以促进将选定的基因组区域转移到目标品种中，从而提供了一种新的解决方案，使育种更快，更有效。该工作计划将模式植物拟南芥中的快速测试与马铃薯中天然和工程单倍体诱导系统的探索相结合，以开发快速简单的作物新性状渐渗方法。本研究的具体目标是：1）以S. tuberosum phureja单倍体诱导剂以及操纵着丝粒组蛋白H3。2)使用不同类型的重组机制将限定的染色体区段从供体基因组工程渐渗到受体基因组。通过这项工作产生的有用的马铃薯和拟南芥品系将分别保藏在GRIN NRSP-6（http：//www.ars-grin.gov/nr6/）和ABRC（https：/www.arabidopsis.org/）储存中心。主要研究者的网站（http：//comailab.genomecenter.ucdavis.edu/）也将链接进展情况和资源。

PI: Luca Comai (University of California DavisCo-PIs: Ek Han Tan (University of California Davis); Anne Britt (University of California Davis); Awais Khan (International Potato Center, Peru); Collaborators : Ravi Maruthachalam (IISER-TVM, India); Meredith Bonierbale (International Potato Center, Peru)A common plant breeding procedure involves moving valuable traits, such as disease resistance, from wild relatives to crop varieties. To achieve this, breeders cross a wild variety to a crop variety. The result is called a hybrid, and it mixes genes from both parents. Most of the genes from the wild variety, however, are unsuited for agriculture and must be cast away. This is done by repeated crossing to the crop variety, coupled to selection for the trait of interest, a process called backcrossing that often requires as many as 10 years. This constitutes a dramatic bottleneck to developing new varieties. Therefore, shortening the development time is particularly critical in the face of unexpected crop challenges when human sustenance depends on the rapid development of new, improved varieties. This project addresses this need. It aims at developing a method for rapid deployment of useful traits into crops, using potato as the experimental system. The collaboration between University of California-Davis and the International Potato Center will also train graduate and undergraduate students in genomic-based breeding. The method developed will be applicable in many crop species and will be useful for both basic and applied research.Haploid induction, a process that generates plants with a single genome instead of the two parental ones, can significantly shorten the time it takes to make new varieties. However, no methods have resolved the problem of overcoming linkage drag, the common, negative association of deleterious genes with desirable ones. The project team discovered a method to facilitate the transfer of selected genomic regions to a target variety, providing a novel solution to make breeding faster and more efficient. The work plan combines rapid testing in the model plant Arabidopsis with exploration of natural and engineered haploid inducer systems in potato to develop methods for rapid and simple introgression of new traits in crops. The specific objectives are to 1) Exploit and develop haploid induction systems in potato, based on the S. tuberosum phureja haploid inducer as well as on manipulation of centromeric histone H3. 2) Engineer introgression of defined chromosomal segments from a donor to a recipient genome using different types of recombination mechanisms. Useful potato and Arabidopsis lines produced by this work will be deposited in, respectively, GRIN NRSP-6 (http://www.ars-grin.gov/nr6/) and the ABRC (https:/www.arabidopsis.org/) stock centers. Progress and resources will also be linked from the Principal Investigator's web site (http://comailab.genomecenter.ucdavis.edu/).