XVI International Botanical Congess

The stress-response is a universal and conserved mechanism which allows cells to enhance their survival of adverse conditions. We examined protein production during heat stress of diatoms that differ in their thermo-tolerance. Cells were incubated with 35S-methionine under various heat shock conditions and proteins visualized using SDS-PAGE. To further characterize the de novo induction and shift between isoforms, proteins were visualized using two-dimensional IEF electrophoresis with silver staining. The presence of the inducible isoform of HSP70 protein, a presumed regulator of the response, was confirmed using Western blots and antibody for pea HSP70. The induction of the stress-response required about 8 h at elevated temperature for the thermo-tolerant species and only about 2 h for the thermo-intolerant species. Fax Number (602) 965-6899