TOWARDS PROTEOMICS OF DESICCATION TOLERANCE IN THE RESURRECTION PLANT HABERLEA RHODOPENSIS

Drought is a major environmental constraint of agricultural productivity worldwide. Understanding the molecular basis of drought tolerance in plants is of importance with respect to basic research and for its improvement in crop plants. Resurrection plants are a small group of angiosperms that can survive extreme dehydration to the point of desiccation and are excellent model systems to investigate the mechanisms of desiccation tolerance. We have chosen to study the leaf proteome response to desiccation of the extremely desiccation-tolerant plant Haberlea rhodopensis. We used high-resolution denaturing two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) to compare the proteomes of hydrated control plants to those dehydrated to 16% water content. As a result we were able to separate and quantify a total of 152 and 148 protein spots in control and fully dry plants, respectively. Comparative analysis indicated differences in protein expression profiles between control and treated samples showing 33 proteins specific for the desiccated plants only. A differential protein expression with up-regulated proteins been prevalent as compared to those down-regulated was observed in the desiccated plants. Using native 2D-PAGE we detected two different isoforms of aldehyde dehydrogenase (ALDH) with very high activity in fully dry plants.