Plant & Animal Genomes XI Conference

January 11-15, 2003
Town & Country Convention Center
San Diego, CA

Poster: Genome Sequencing & ESTs
            

SIMPLE SEQUENCE REPEATS LIBRARIES AS A RESOURCE FOR ISOLATION OF EXPRESSED SEQUENCES TAGS (ESTs) IN DURUM WHEAT

¹ Metapontum Agrobios, S.S. Jonica 106, Km 448,2, Metaponto (MT) 75010 Italy

² FIUOTECNICA, S.S. Jonica 106, Km 448,2, Metaponto (MT) 75010 Italy

Simple sequence repeats (SSRs), also called microsatellites, consist of tandemly repeated units of DNA such as (GA)n or (GT)n that are widely interspersed in eukaryotic genomes. In order to isolate microsatellite markers in tetraploid wheat (Triticum turgidum L. ssp durum), we constructed two small insert genomic libraries highly enriched in GA/CT and CA/GT repeats. About 500 of them were directly subjected to sequence analysis and the sequence results revealed that 55% of the clones contained SSR regions. The BLAST similarity searches against NCBI sequence database revealed that a large number of clones showed similarity with ESTs sequence. In this study we present the initial identification of putative genes containing repeated regions with macroarray analysis. Two sets of nylon filters were arrayed with GA (1248) and CA (1345) recombinant clones, respectively, and screened with radio-labelled “totipotent” mRNA (patent pending) containing a representation of most of mRNA, regardless of the developmental stage in the original material. The preliminary results of the hybridisation experiments show that the frequency of repeated motifs in expressed regions is 0.7% of the screened clones.