Plant, Animal & Microbe Genomes X Conference

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

Poster: Genome Sequencing & ESTs
            

EXPRESSION PROFILE OF ESTS INDUCED BY ALUMINUM STRESS IN WHEAT

¹ 368 Agricultural Hall, Dept. of Plant and soil Sciences, Oklahoma State University, Stillwater, OK 74078 USA

Increased soil Al-toxicity due to a gradual decline in soil pH has resulted in significant losses in wheat (Triticum aestivum) yield in the southern Great Plains. Elucidating the global expression pattern of wheat Al-tolerance genes may lead to new gene discovery and further understanding genetic mechanisms of wheat tolerance to Al toxicity. To enrich differentially expressed sequence tags (ESTs) for Al tolerance, cDNA subtraction libraries were generated from Al-stressed roots of two near-isogenic lines (NILs) differing in a Al tolerance gene from Atlas 66, using the suppression subtractive hybridization method. Expression of the ESTs at three Al-treatment durations (6 h, 48 h and 7 d) was investigated with macroarrays including 1300 clones from the libraries. Expression levels of one-third of the ESTs were significantly altered for both NILs in response to different durations of Al-stresses. The highly expressed clones were sequenced and about 20% of them exhibited high similarities to genes involved in signal transduction, membrane transportation, and cell defense and rescue processes, suggesting that wheat response to Al stress may involve a complicated defense-related signaling pathway. Several ESTs showed consistently increased expression only in the tolerant NIL after Al treatments, indicating that those ESTs may play significant roles on enhancing wheat tolerance to Al toxicity.