0023-6152

AA00697606

6796251

This study aims to examine the characteristics of vacuole ATPase (V–ATPase) activities and protein expression in vacuole fractions isolated from the common ice plant (Mesembryanthemum crystallinum L.) grown under control and salt–stressed conditions, using various centrifugation conditions of sucrose density gradient. The protein samples were analyzed using two–dimensional electrophoresis (2DE) gels. The results reveal that the vacuolar fractions collected at 20%, 30%, and 40% (w/w) sucrose density in the 0 mM, 100 mM, and 400 mM NaCl–stressed plants, respectively, exhibited the highest V–ATPase activities. Using the differential display with 2DE gels, the proteins in the vacuole fractions were analyzed, and the abundant proteins on each gel were identified based on their isoelectric points and molecular weights. The Arabidopsis database and the ExPASy–TagIdent tool were used to estimate the proteins. The results show 165, 194, and 199 abundant proteins with 41, 51, and 53 different proteins relating to the vacuole fractions among control samples (0 mM NaCl) and salt–stressed samples at 100 mM NaCl and 400 mM NaCl, respectively. Although the proteins on each 2DE gel varied among the samples, they were generally focused on ten physiological function groups, including pump proteins, transporter proteins, metal channel proteins, peptide transport proteins, channel proteins, stress response proteins, protease proteins, autophagic proteins, stress response proteins, and unknown proteins.