Plant, Animal & Microbe Genomes X Conference

January 12-16, 2002
Town & Country Convention Center
San Diego, CA

Poster: Genome Sequencing & ESTs
            

GENOMIC SEQUENCING REVEALS GENE CONTENT, GENOMIC ORGANIZATION, AND RECOMBINATION RELATIONSHIPS IN BARLEY

¹ Department of Crop and Soil Sciences, Washington State University, Pullman, WA 99164, USA

² Department of Bio-Resorces, National Institute of Agricultural Science & Technology, Suwon 441-707, Republic of Korea

³ Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA

⁴ National Center for Genome Resources, 2935 Rodeo Park Drive East, Santa Fe, NM 87505, USA

⁵ Department of Agronomy, University of Nebraska - Lincoln, NE  68583-0915, USA

Plants vary widely in their nuclear DNA content, but the number of coding sequences appears to be conserved. Studies in large-genome cereals indicated that genes are organized into gene islands separated by repetitive sequences (Panstruga et al. 1998, NAR, 26:1056; San Miguel et al. 1996, Science, 274:765). Studies of genome organization in barley (Hordeum vulgare L.) would provide information about the evolution of large genomes and result in efficient approaches to analyzing the coding portions of the genome. Until now studies of the barley genome were restricted to genetic and physical mapping and rather limited sequence data. Here we report sequence and analysis of 4 barley BAC clones from chromosomes 2(2H) bin 013 (selected with probe bcd135), 5(1H) bin 002 (probe bcd1434), 6(6H) bin 007 (probe rz567) and 1(7H) bin 002 (probe wx1). We identified putative genes and repetitive sequences and analyzed their structure. Together with previously published sequences from chromosome 5(1H) WG644 locus, chromosome 2(2H) Rar1 locus and chromosome 4(4H) Mlo locus, our sequences form a set of contiguous barley sequences from 5 of the 7 chromosomes. BAC clones were derived from genomic locations with different recombination frequencies according to the barley physical map by Kunzel et al. 2000, Genetics, 154:397. We estimated average gene density to be ca. one gene per 20 kb consistent with previously reported values. Relationship of gene density and recombination frequencies of corresponding chromosomal locations will be discussed.