|Samac, Deborah - Debby|
Submitted to: International Symposium on Phosphorus Dynamics in the Soil Plant Continuum
Publication Type: Abstract Only
Publication Acceptance Date: 6/13/2003
Publication Date: N/A
Technical Abstract: Phosphorus (P) is essential for plant growth and development. Its deficiency leads to the activation of genes with various functions in enhancing P uptake and utilization. Phosphate transporter and acid phosphatase genes are two important P-deficiency induced genes in higher plants. We previously reported the cloning of a phosphate transporter gene LaPT1 and an acid phosphatase gene LaSAP1 from white lupin (Lupinus albus) and demonstrated enhanced gene expression in response to P deficiency. Here we provide further details of the temporal and spatial pattern of LaPT1 and LaSAP1 promoter activity by introducing promoter::GUS reporter gene fusions into another legume species, alfalfa (Medicago sativa). Both LaPT1::GUS and LaSAP1::GUS reporter genes showed significant induction by P deficiency in transgenic alfalfa. In addition, we also characterized a MYB gene whose expression seems to be modulated by exogenous phosphate at early developmental stages. A MYB::GUS reporter was also introduced in alfalfa and the transgenic plants are being analyzed.