PAG-XIII  Plant & Animal Genomes XIII Conference

January 15-19, 2005
Town & Country Convention Center
San Diego, CA


W037 : Barley

High-Throughput Physical Mapping Of Barley Genes In Wheat-Barley Chromosome Addition Lines

Gary J Muehlbauer1 , Seungho Cho1 , David F Garvin2

1  Dept. of Agronomy and Plant Genetics, University of Minnesota, St. Paul, MN 55108, USA
2  USDA-ARS Plant Science Research Unit, Dept. of Agronomy and Plant Genetics, University of Minnesota, St. Paul, MN 55108, USA

Barley chromosome addition lines of wheat are excellent genetic stocks for physical mapping genes to barley chromosomes. Wheat-barley addition lines were developed through wide crosses of Betzes barley with Chinese Spring wheat and contain a full complement of wheat chromosomes with a single barley chromosome. Disomic addition lines are available for barley chromosomes 2H, 3H, 4H, 5H, 6H and 7H, and ditelosomic addition lines are available for 13 of the 14 barley chromosome arms. We used the Barley1 Affymetrix GeneChip probe array to examine transcript accumulation in Betzes barley, Chinese Spring wheat, and the wheat-barley addition lines. Transcripts that were detected in Betzes and an addition line but not in Chinese Spring were physically mapped to the added barley chromosome. We identified 6,470 transcripts in Betzes but not in Chinese Spring, and 1022, 1017, 817, 1038, 561, and 1088 of them were specifically detected in the disomic chromosome 2H, 3H, 4H, 5H, 6H, and 7H addition lines, respectively. We validated the physical location of these genes through examining transcript accumulation in the 6HS, 6HL and 2HL ditelosomic addition lines, in silico comparative mapping to rice and wheat, and genomic PCR. Our validation data show a remarkable consistency with the physical location. In addition, we used our data to examine gene duplication in the barley genome and these results will be discussed. Our results show that the use of GeneChips in combination with the wheat-barley addition lines is a powerful approach to physical mapping and examining genome organization in barley.