Large scale mapping of wheat transcripts and simultaneously defining the A B and D genome contribution to the hexaploid transcriptome

面包小麦是英国的主要可耕种作物。当前和不断上涨的谷物价格、将小麦用作生物乙醇的便利来源以及未来可能出现的粮食安全问题表明，在可预见的未来，英国小麦种植数量增加的趋势可能会持续下去。然而，培育产量更高或抗病更强的小麦新品种是一项长期的工作，需要在受过培训的人员和资源上进行大量投资(并留住)。分子标记在小麦育种中的应用越来越多；然而，面包小麦的六倍体特性(它包含来自三个不同物种的DNA)限制了与农艺性状相关的标记的开发。包括我在布里斯托尔的小组在内的各个小组的工作正在缓慢地导致有用标记的数量增加，以至于现在有数百个微卫星或单核苷酸多态(SNPs)可用于常规用途。然而，当你将六倍体小麦的情况与二倍体大麦的情况进行比较时，你会立即看到与多倍体作物(即具有来自不止一个物种的DNA的作物)合作的相当大的缺点。利用BBSRC工具和资源发展基金12个月的奖励提供的资金，我的团队已经产生了一种新型的小麦微阵列，它包含244,000个特征，能够区分来自面包小麦基因组中三个不同物种的基因(244K小麦阵列)。因此，这个阵列能够像分析二倍体一样分析小麦。正如我们最初的T&R建议，我的团队现在已经验证了这个阵列，并产生了初步数据，表明这个独特的资源能够区分六倍体小麦的三个基因组，并同时产生大量单个转录本的信息。在这一应用中，我们建议使用244K小麦阵列来定位数千个小麦转录本(并为植物育种者和遗传学家实现一个重要的战略目标)，并解决基于组成异源六倍体小麦的三个基因组之间相互作用的假设研究。

Bread wheat is the dominant UK arable crop. Current and increasing grain prices, the use of wheat as a convenient source of bioethanol and possible future food security issues, suggest that the trend to grow increased amounts of wheat in the UK might continue for the foreseeable future. However, the generation of new higher yielding or more disease resistant wheat varieties is a long term business, requiring considerable investment in (and retention of) trained personnel and resources. The use of molecular markers in wheat breeding is increasing; however the hexaploid nature of bread wheat (it contains DNA from three separate species) has limited the development of markers linked to agronomic traits. Work by various groups including my group at Bristol is slowly resulting in an increase in the number of useful markers such that there are now a few hundred microsatellites or Single Nucleotide Polymorphisms (SNPs) available for routine use. However, when one compares the situation in hexaploid wheat with that in diploid barley, where several thousand SNP-based markers are available, one immediately sees the considerable disadvantages of working with a polyploid crop (i.e. crops with the DNA from more than one species). Using funds provided by a 12 month BBSRC Tools & Resources Development Fund award my group has generated a new type of wheat microarray containing 244,000 features which is capable of discriminating between the genes from the three different species within the bread wheat genome (244K wheat array). Hence this array is capable of analysing wheat as though it were a diploid. As described our original T&R proposal my group has now validated this array and generated preliminary data which shows that this unique resource is capable of discriminating between the three genomes of hexaploid wheat and simultaneously generating information on large numbers of individual transcripts. In this application we propose to use the 244K wheat array to map several thousand wheat transcripts (and achieve an important and strategic goal for plant breeders and geneticists) and address hypotheses based research on the interaction between the three genomes that make up allohexaploid wheat.