Microarray Analysis of Late Response to Boron Toxicity in Barley (Hordeum vulgare L.) Leaves

Authors : Mehmet Tufan ÖZ, Remziye YILMAZ, Füsun EYİDOĞAN, Leo de GRAAFF

Pages : 191-202

View : 28 | Download : 10

Publication Date : 2009-04-01

Article Type : Research Paper

Abstract :DNA microarrays, being high-density and high-throughput, allow quantitative analyses of thousands of genes and their expression patterns in parallel. In this study, Barley1 GeneChip was used to investigate transcriptome changes associated with boron insert ignore into journalissuearticles values(B); toxicity in a sensitive barley cultivar insert ignore into journalissuearticles values(Hordeum vulgare L. cv. Hamidiye);. Eight-day-old aseptically grown seedlings were subjected to 5 or 10 mM boric acid insert ignore into journalissuearticles values(Binsert ignore into journalissuearticles values(OH);3); treatments for 5 days and expression profiles were determined with DNA microarrays using total RNA from leaf tissues. Among the 22,840 transcripts - each represented with a probe set on the GeneChip - 19,424 probe sets showed intensity values greater than 20th percentile in at least one of the hybridizations. Compared to control insert ignore into journalissuearticles values(10 mM Binsert ignore into journalissuearticles values(OH);3);, 5 mM Binsert ignore into journalissuearticles values(OH);3 treatment resulted in differential expression of 168 genes at least by twofold. Moreover, 10 mM Binsert ignore into journalissuearticles values(OH);3 treatment resulted in at least twofold induction or reduction in expression of 312 transcripts. Among these genes, 37 and 61 exhibited significantly insert ignore into journalissuearticles values(P < 0.05); altered levels of expression under 5 and 10 mM Binsert ignore into journalissuearticles values(OH);3 treatments, respectively. Differentially expressed genes were characterized using expression-based clustering and HarvEST:Barley. Investigations of expression profiles revealed that B toxicity results in global changes in the barley transcriptome and networks of signaling or molecular responses. A noticeable feature of response to B was that it is highly interconnected with responses to various environmental stresses. Additionally, induction of jasmonic acid related genes was found to be an important late response to B toxicity. Determination of responsive genes will shed light on successive studies aiming to elucidate molecular mechanism of B toxicity or tolerance. To the best of our knowledge, this is the first report on global expression analysis of barley seedlings under B toxicity.
Keywords : Barley, Barley1 GeneChip, Boron toxicity, Gene expression, Microarray, Transcriptome analysis