Submitted to: American Society of Plant Biologists Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: March 19, 2004
Publication Date: July 24, 2004
Citation: Maron, L.G., Moore, S., Giovannoni, J.J., Kochian, L.V. 2004. Monitoring gene expression profiles in response to aluminum stress in maize roots using cdna microarrays. American Society of Plant Biologists Annual Meeting. p. 77. Technical Abstract: Aluminum (Al) toxicity is the major factor limiting crop productivity on acid soils, which comprise up to 40% of the world's arable lands, primarily by inhibition of root growth and nutrient/water acquisition. Genetic variation for Al tolerance exists in many crops, and breeders have explored it for many years to develop varieties with increased Al tolerance. The underlying physiological and genetic bases for Al-tolerance are not well understood. Al tolerance has been correlated with an Al-inducible release of ligands (e.g. organic acids) that may reduce Al uptake by roots in a variety of plants. However, no genes relevant for Al tolerance have been cloned and characterized. The identification of genetic factors underlying the responses of crop plants to aluminum stress will provide a basis for improving aluminum tolerance. With the goal of identifying genes likely to be involved in Al tolerance in maize, we are using ZmDB Unigene microarrays to monitor changes in gene expression in roots under aluminum treatment. Gene expression profiling is being performed in two maize genotypes: Cateto Al 237/67 (Al-tolerant) and L53 (Al-sensitive). The profiling will be extended to additional genotypes, and genes that are consistently expressed under Al treatment in tolerant but not in sensitive genotypes will be considered candidates for possible roles in Al tolerance. Northern blots on a random subset of the genes are being used to validate the DNA microarray data, and cluster-based analysis will be performed to identify suites of genes relevant to Al tolerance. Supported by USDA-NRI Competitive Grant #2001-35301-10647 to LVK and a CAPES (Brazil) fellowship to LGM.