Poster: Salinity
Abs #
127: Mechanisms enabling salt tolerant plants to grow in saline environments
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Presenter: |
Pagliarulo, Christopher L, Contact Author |
Authors | Pagliarulo, Christopher L (A) Kim, YongSig (A) Mohr, Peter G (A) Tax, Frans E (A) Schumaker, Karen S (A) | | Affiliations: |
(A): University of Arizona
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Accumulation of salt (NaCl) in the soil adversely affects nearly 20% of irrigated agricultural land worldwide. While most crop plants are sensitive to soil salinity (glycophytes), plants tolerant to salt accumulation (halophytes) have been identified. Previous studies have suggested that halophytes achieve tolerance by maintenance of low cytoplasmic Na+ levels. Studies with the model glycophyte Arabidopsis thaliana have identified the Salt-Overly-Sensitive (SOS) pathway which regulates cellular Na+ levels. A key component of this pathway is SOS1, a protein that transports Na+ from the cytoplasm out of the cell. Genes encoding SOS1 have been identified in several glycophytes, however its role in halophyte salt tolerance is not known. A putative SOS1 ortholog has been identified in Thellungiella halophila, a genetically tractable, salt-tolerant relative of Arabidopsis. Identification of SOS1 in T. halophila suggests that it possesses the same genes and proteins (hardware) for regulating Na+ levels as Arabidopsis. The goal of our research is to understand how T. halophila regulates that hardware to enable growth in near sea water levels of salt. To do this, we are: (1) modifying T. halophila SOS1 gene expression programs using RNA interference to establish if SOS1 plays a primary role in salt tolerance, (2) comparing SOS1 expression in T. halophila and Arabidopsis throughout development and in response to environmental stress to determine if differences in transcriptional regulation are important for attaining greater tolerance, and (3) expressing the ThSOS1 coding and regulatory regions in an Arabidopsis sos1 loss of function mutant to understand if differences in protein function or regulation support tolerance. (Supported by SWC grant 04N07 and NSF GRF to CLP)
