Assessment of Gene Content, Colinearity and Evolution in Barley, Maize, Rice, Sorghum and Wheat

该项目的总体目标是确定几种重要植物基因组的结构、组成和进化：大麦、玉米、水稻、高粱和小麦。植物的染色体非常大，结构也很复杂，尽管不同的植物物种在染色体中所含的DNA数量上存在500多倍的差异。尽管DNA数量有如此巨大的差异，但基因含量似乎变化相对较小。因此，确定植物染色体中DNA含量的性质以及这些DNA(特别是基因)是如何排列的将是有价值的。被称为草的植物家族，包括大麦、玉米、水稻、高粱和小麦，提供了世界上大部分的食物，也有相当密切的亲缘关系。然而，它们在基因组大小上的差异超过11倍，并且具有非常不同的最佳生长环境和产量潜力。这项研究将调查这五个基因组中四到五个进化相关区域的序列组成。该方法将为每个基因组产生大约100千碱基对片段的DNA序列，在细菌人工染色体载体中以克隆的形式分离。然后将分析这些序列的基因内容和组织，以及其他类型DNA的存在和性质。这些结果将表明草的染色体是如何组成的，以及它们是如何进化的。这一知识将使所有实验室在基因分离、基因研究和基因工程方面采用更有效的技术。

The overall goal of the project is to determine the structure, composition and evolution of several important plant genomes: barley, maize, rice, sorghum and wheat. The chromosomes of plants are very large and complex in structure, although different plant species vary by over 500 fold in the amount of DNA contained within the chromosomes. Despite this tremendous variation in DNA amount, gene content appears to vary relatively little. Hence, it would be valuable to determine the nature of the DNA content in the chromosomes of plants, and how these DNAs (especially genes) are arranged. The family of plants called grasses, including barley, maize, rice, sorghum and wheat, provide most of the world's food and are also fairly closely related. Yet they differ over 11 fold in genome size and have very different optimal growth environments and yield potential. This study will investigate the composition of sequences in four to five evolutionarily-related regions of these five genomes. The approach will be to generate the DNA sequence of approximately 100 kilobase pair segments for each genome, isolated as clones in bacterial artificial chromosome vectors. These sequences will then be analyzed for gene content and organization, and for the presence and nature of other types of DNAs. These results will indicate how grass chromosomes are composed and how they evolve. This knowledge will permit more efficient techniques in all laboratories for gene isolation, for gene study, and for genetic engineering.