Poster: Salinity

Abs # 165: Overexpression of the salt- and water-stress regulated Asr1 gene improve plant salt tolerance

Presenter:	Bar-Zvi, Dudy , barzvi@bgumail.bgu.ac.il
Authors	Bar-Zvi, Dudy  (A)   Yossi, Kalifa  (A)   Zvia, Conrad  (A)
Affiliations:	(A): Ben-Gurion University, Beer-Sheva, Israel

Tomato ASR1 is a highly charged acid soluble 13 kDa protein. Basal levels of Asr1 transcripts and ASR1 protein are detected in vegetative organs of irrigated tomato plants. These levels transiently increase in response to salt-stress, osmotic-stress or treatment with ABA. In vitro studies showed that purified ASR1 protein has a zinc-dependent DNA-binding activity. Tobacco plants were transformed with Asr1 cDNA under the control of 35S promoter of the cauliflower mosaic virus. ASR1 protein was immunolocalized in both cytoplasmic and nuclear compartments. ASR1 over expressing plants were assayed for salt tolerance. Seeds of transgenic tobacco plants over expressing of the tomato ASR1 protein germinated better in the presence of salt than non-transformed tobacco plants. ASR1 overexpressing plants survived salt-shock under conditions that resulted in the death of wt plants. ASR1 overexpressing transgenic plants accumulate less Na+ and proline than wt plants in response to salt stress. Overexpression of ASR1 resulted in the induction of other genes in the absence of stress conditions. These results suggest that ASR1 protein may play a role in water-stress and salt-stress response and probably is part of the signal transduction pathway resulting in the alteration of gene expression upon water and salt stresses.