Plant & Animal Genomes XI Conference Plant & Animal Genomes XI ConferenceJanuary 11-15, 2003
Town & Country Convention Center
San Diego, CA
Poster: Genome Sequencing & ESTs
The discovery of genes controlling various functions of living creatures is one of the most important issues in bioscience. Gene expression profile analysis by random EST sequencing followed by computer-associated comparison of the transcription level of each gene locus, a methodology also known as "digital Northern ", is one promising strategy for gene discovery. In this study, we developed a user-friendly computer system to assist such analysis, and used it in combination with a 3'-EST library construction procedure enabling close reflection of the transcription profiles in living cells. The advantage of this system is that one can comprehensively compare gene expression profiles in various tissues, under various conditions, at different time points or at different growth stages. Besides, as traits usually reflect their genetic background, analyses using strains with and without the trait of interest under certain conditions should reveal trait-related genes. We analyzed gene expression profiles in several organs or tissues of rice ( Oryza sativa L.) grown normally or treated with various stresses, including submergence, low temperature, and herbicide. Two cultivars with different levels of cold-tolerance in the juvenile phase subjected to cold stress were also analyzed. The results revealed gene sets specifically or significantly up- or down-regulated in each organ or tissue, under each stress, in each strain. Some genes showing different expression profiles between strains were closely linked to known cold-resistance QTLs. 3'-EST libraries obtained in these analyses were successfully used as sources for microarray probes. The results of application to microarray analysis will be reported.