|Ainsworth, Elizabeth - Lisa|
Submitted to: American Society of Plant Biologists Annual Meeting
Publication Type: Proceedings
Publication Acceptance Date: 7/23/2005
Publication Date: N/A
Citation: N/A Interpretive Summary: Three genotypes of Arabidopsis thaliana and the closely related species Thellungiella halophila were grown at elevated atmospheric CO2 concentrations in the field for approximately 2 weeks. Microarrays were used to investigate changes in gene expression associated with growth at elevated CO2. There was a core set of genes that changed in all 3 ecotypes and T. halophila, indicating CO2 response pathways. These pathways included genes associated with photosynthesis and chloroplast localization, and carbon and nitrogen metabolism.
Technical Abstract: The purpose of this research was to study, understand, and model how three ecotypes of the model species, Arabidopsis thaliana, and a close relative Thellungiella halophila, behave in elevated [CO2] in the field. Three years (2002, 2003 and 2005) of experiments showed that Arabidopsis can grow well in the field in June, with Fv/Fm recovering within 3 days after transplanting to the field. Significant differences between treatments and cultivars were consistently observed. CO2 exposure initiated different strategies among the lines with respect to genes related to carbohydrate synthesis and partitioning, cell wall biosynthesis, N-allocation/amino acid metabolism, and stress responses. Among genes associated with metabolic functions, enzymes in nitrogen/amino acid metabolism, organic acid, and lipid metabolic functions were of note. Irrespective of the underlying genetic diversity that distinguished ecotypes, a core set of signature processes and genes reporting atmospheric CO2 response pathways united Thellungiella and the three Arabidopsis ecotypes. Genes associated with photosynthesis and chloroplast localization were most highly represented in down-regulated group, while C, N metabolism and redox responses were over-represented among the up-regulated genes.