591 / 2019-04-17 16:11:55

The uncharacterized Salt Tolerance-Related Protein (STRP) of Arabidopsis thaliana is a new player in cold stress response

cold stress,abscisic acid,Salt tolerant related protein,Arabidopsis thaliana

全体主题 > Abiotic Stress

Cold is one of the critical environmental conditions that negatively affects plant growth and development. STRP is an A. thaliana poorly characterized protein identified in a proteomic screen of temperature stress-responsive proteins. Here we studied the role of this protein in response to cold stress. Our experiments show a rapid increase of STRP into the cytosol after cold treatment caused by increased protein stability. By means of specific proteasome inhibitor we demonstrate that cold stress inhibits the proteasome-mediated degradation of STRP. Protoplasts transiently transformed with the fusion protein STRP-YFP show that STRP is located into the cytosol, in the nucleus and is associated to the membrane. Under cold stress protein levels into the nucleus and in the cytosol increase, whereas the fraction associated to the membrane decreases.
To clarify the physiological function of STRP and its role in response to cold stress, we studied the cold response in the strp knockout mutants. This mutant is smaller compared to wild type plants both under physiological and stress conditions and is more susceptible to the oxidative damages induced by cold stress. Furthermore, the analysis of Abscisic acid (ABA) effects on growth and development of strp plants demonstrates that the mutant displays an ABA hyposensitive phenotype. These evidences demonstrate the crucial role of STRP in cold stress response and in the regulation of ABA biosynthesis and signaling.