Effect of chromatin modification on meiosis: wheat, a model for polyploid crops

该项目将解决一个重要问题，该问题阻碍了有效利用小麦野生亲缘植物的遗传多样性。能够与野生近缘种合作，将有益的特性引入小麦将是一项重大的科学成就，并大大改善育种者培育性能更高的小麦新品种的方式。一些野生近缘种适应于在与国内小麦不同的气候条件下茁壮成长，或者它们具有对重要疾病的天然抗性和/或具有可能影响产量的其它重要特性。我们想要做的是生产能够利用这种多样性的工具，并从基因上将这些有利的特征引入小麦。通过这样做，我们将使小麦育种者能够以可持续的方式改善小麦性能，提高产量，引入抗病性和耐旱性。在少数情况下，这已经实现。是什么阻止了野生亲戚的有效利用？野生近缘种和小麦染色体必须在减数分裂期间对齐并有效地交换（重组）。没有重组，就没有机会将野生近缘种的遗传多样性引入小麦。Ph 1基因座大大减少了野生近缘种和小麦染色体之间的重组。Ph 1甚至减少来自小麦地方品种的染色体之间的重组，在那里它们显着分歧。这使得野生近缘种在减数分裂过程中通过重组进行基因转移变得困难，而地方种则效率低下。那么我们如何克服这个问题呢？在小麦中，Ph 1基因座调节重组。理解Ph 1法规将使我们深入了解这一过程。它将为我们提供如何在小麦中选择重组位点的理解，并由此引出如何根据特定需求改变和定制该过程，从而使我们能够操纵它进行植物育种。

This project will address an important problem which has hampered the efficient exploitation of the genetic diversity held within wild relatives of wheat. Being able to work with wild relatives so that beneficial characteristics can be introduced into wheat will be a major scientific achievement and dramatically improve the way breeders can generate new varieties of wheat with increased performance.Some wild relatives are adapted to thrive under different climatic conditions to that of domestic wheat, or they carry natural resistance to important diseases and/or carry other important characteristics which could influence yield. What we want to do is to produce the tools which will allow the exploitation of this diversity and genetically introduce these favourable characteristics into wheat. In doing so we will be enable wheat breeders to, amongst other things, improve wheat performance in a sustainable way, increase yield, introduce disease resistance and drought tolerance.In a small number of cases this has already been achieved. What stops wild relatives being used efficiently? The wild relative and the wheat chromosomes must align and efficiently exchange (recombine) during meiosis. Without recombination, there isn't the opportunity to introduce the genetic diversity of wild relatives into wheat. The Ph1 locus substantially reduces recombination between wild relative and wheat chromosomes. Ph1 even reduces recombination between chromosomes derived from wheat landraces where they are significantly diverged. This makes gene transfer by recombination during meiosis difficult in the case of wild relatives, or inefficient in the case of landraces.So how can we overcome this problem? In wheat, the Ph1 locus regulates recombination. Understanding this Ph1 regulation will provide us with an insight into this process. It will provide us with an understanding of how recombination sites are selected in wheat, and leading from this , how the process can be altered and tailored for specific needs, thus enabling us manipulate it for plant breeding.