Reduced Na+ uptake in the NaCl-hypersensitive sos1 mutant of Arabidopsis thaliana

摘要: sos1 is an Arabidopsis thaliana mutant with >20 times higher sensitivity toward Na+ inhibition due to a defective high-affinity potassium-uptake system. We report here that accumulates less than the wild type in response NaCl stress. The contents seedlings exposed 25 mM for 2 or more d are about 43% lower those type. When assayed at 20 external NaCl, pretreated low potassium have 32% uptake However, little difference could be measured when were not potassium. Low-potassium treatment was shown induce activity seedlings. No substantial efflux between and detected. results show reduced accumulation influx rate. Therefore, mutation appears disrupt low-affinity addition its impairment of K+ uptake.