A Radiation Hybrid System for the Genetic and Physical Mapping of the Corn Genome

庞大而复杂的玉米基因组阻碍了综合制图和测序工作。然而，所有玉米基因的预期分离表明，迫切需要有效的定位系统和/或降低基因组的复杂性。本研究通过开发多功能遗传材料解决了这一需求，包括能够快速物理地将DNA序列映射到1 Mbp或更少的染色体和染色体片段。这些材料与微阵列技术相结合，将允许在一组实验中绘制数千个序列。完整的燕麦-玉米染色体附加系已恢复。将序列与10个添加的DNA杂交允许将序列放置到染色体上，包括重复序列或多基因家族。辐射杂交（RH）系然后由附加系的伽马辐照产生。研究将集中于为所有10个新增植物获得可育系，并为所有10条染色体创建RH制图面板。初步数据表明，对基因（ESTs和已知基因）进行染色体和染色体片段的高效物理定位，以及对重复序列的识别和定位是可行的。在斯坦福大学分离的无害环境技术将首先被绘制。RH物理图谱将通过提供亚染色体片段水平的支架来补充其他玉米物理图谱系统。这项更新的具体目标是：(1)恢复一套完整的可育燕麦-玉米附加系，并表征附加系和RH系的表型、细胞学、染色体稳定性和遗传；(2)制作所有10个个体染色体的RH制图板，用于低分辨率和高分辨率制图；(3)为候选基因的发现和比较基因组研究提供高通量的ESTs染色体区域定位。每条玉米染色体的可育燕麦-玉米附加系；附加系的种子、组织或DNA进行分布。2. 辐射杂交系的DNA图谱，用于每条染色体的低分辨率和高分辨率定位。每条染色体的辐射杂交图谱，以及适当的资源，将允许其他研究人员在一到五兆碱基内物理地绘制基因图谱。一个序列映射到染色体和辐射杂交系的数据库，当这些系可用时。提供给现有网络资源的数据。5 .利用微阵列技术和燕麦-玉米附加系的基因组DNA测量每条染色体重复序列的相对数量数据。描述遗传物质、辐射杂交图谱和序列图谱的网络资源。项目地址：明尼苏达大学，农学和植物遗传学系411 Borlaug Hall， 1991上布福德圈，圣保罗市，MN 55108项目信息的互联网地址（Web和电子邮件）：http://agronomy.coafes.umn.edu/cornpep/nsf/

The large and complex genome of corn has impeded integrated mapping and sequencing efforts. The anticipated isolation of all the corn genes, however, indicates the pressing need for efficient mapping systems and/or a reduction in genome complexity. This research addresses the need by developing multifunctional genetic materials that include the ability to rapidly physically map DNA sequences to chromosomes and chromosome segments of 1 Mbp or less. These materials coupled with microarray technology will allow the mapping of thousands of sequences in a single set of experiments. The complete set of oat-corn chromosome addition lines has been recovered. Hybridization of sequences to DNA of the 10 additions allows placement of sequences to chromosome including duplicated sequences or multigene families. Radiation hybrid (RH) lines are then produced by gamma irradiation of the addition lines. The research will focus on obtaining fertile lines for all 10 addition plants and on creating RH mapping panels for all 10 chromosomes. Preliminary data indicates the feasibility for efficient physical mapping of genes (ESTs and known genes) to chromosome and chromosome segment, and the identification and mapping of duplicated sequences. The ESTs isolated at Stanford University will initially be mapped. An RH physical map will complement other corn physical mapping systems by providing a scaffold at the subchromosomal fragment level. The specific objectives of this renewal are to (1) recover a complete set of fertile oat-corn addition lines and characterize the phenotype, cytology, chromosome stability and transmission of the addition and RH lines; (2) produce RH mapping panels for all 10 individual chromosomes for both low and high resolution mapping; (3) enable high-throughput mapping of ESTs to chromosomal regions for candidate gene discovery and comparative genome studies.Deliverables:1. Fertile oat-corn addition lines for each corn chromosome; seed, tissue or DNA of the addition lines for distribution. 2. DNA panels of radiation hybrid lines for low and high-resolution mapping of each chromosome.3. Radiation hybrid mapping panels for each chromosome, along with appropriate resources that will allow other researchers to physically map genes to within one to five megabases.4. A database of sequences mapped to chromosome and to radiation hybrid lines as the lines become available. Data to be provided to existing web resources.5. Data about relative quantities of repetitive sequences per chromosome measured using microarray technology with genomic DNA from the oat-corn addition lines.6. Web resources describing genetic materials, radiation hybrid mapping, and sequences mapped.Project address: University of Minnesota, Dept. of Agronomy and Plant Genetics 411 Borlaug Hall, 1991 Upper Buford Circle, St. Paul, MN 55108 Internet Addresses (Web and E-mail) for Project Information: http://agronomy.coafes.umn.edu/cornpep/nsf/