Proteomics and molecular biology of abiotic stress response and tolerance

(New) EST Database

Proline accumulation and MAPKinase activation under salt and metal stress

Proline is the most widely studied molecule that accumulates in plants under salt stress. Although the compound has been suggested to act as an osmoticum under salt and drought stress, the functional significance of its accumulation is, however, yet to be elucidated well as the compound has also been reported to accumulate in plants in response to environmental stresses like heavy metals, UV radiation, temperature, etc besides in response to drought and salinity. Moreover, the mechanism triggering its accumulation is not yet clear. As the stress signal is perceived from the external environment, the MAPKinase cascade could be involved in transduction of the signal leading to accumulation of the compound. All these are being investigated under this project.

Characterization of superoxide dismutases and other important antioxidative enzymes from halophiles

Appearance of new isoforms of antioxidative enzymes like superoxide dismutase and catalase under salt and drought stress provides circumstantial evidence of involvement of the anitoxidative machinery of plants in salt and drought tolerance. However, the relationship is not yet established. Possible relationship between the antioxidative enzymes and salt/drought tolerance can be delineated further only by isolotation and characterization of the enzymes from extremophiles (halophiles) and studying their expression pattern under stress condition. Mangrove plants and facultative salt tolerant algae are being used to understand the relationship.

Identification and characterization of enzymes/proteins involved in maintaining ion-homeostasis, their expression and regulation

Controlled of entry of Na+, the major ionic component of salinity, into the cells and/or its intracellular sequestration is supposed to be one of the way by which plant is able to tolerate elevated salinity condition. Although the details of the mechanism are not understood well, the membrane bound enzyme, H+ATPase, is believed to play important role in this regard. The project plans to understand and elucidate its role further in salinity tolerance.

Proteomics of abiotic stress response

Stress adaptive response is generally mediated or regulated through protein synthesis, which depending upon requirement of the stress condition may be up-regulated, down regulated or newly synthesized. 2-D PAGE is the technique, which give information on these aspects. Identification of the differentially expressed protein under stress condition may throw information on the stress responses observed in an organism at biochemical and phenotypic level. Use of salt and metal tolerant plants are planned to identify the protein(s) responsible for adaptation to these stresses