Sottosanto Jordan B, Gelli Angie, Blumwald Eduardo
Department of Pomology, University of California, One Shields Ave, Davis, CA 95616, USA.
Plant J. 2004 Dec;40(5):752-71. doi: 10.1111/j.1365-313X.2004.02253.x.
AtNHX1, a vacuolar cation/proton antiporter of Arabidopsis, plays an important role in salt tolerance, ion homeostasis and development. We used the T-DNA insertional mutant of AtNHX1 (nhx1 plants) and Affymetrix ATH1 DNA arrays to assess differences in transcriptional profiles and further characterize the roles of a vacuolar cation/proton antiporter. Mature, soil-grown plants were used in this study to approximate typical physiological growing conditions. A comparison of plants grown in the absence of salt stress yielded many transcripts that were affected by the absence of the AtNHX1 vacuolar antiporter. Furthermore, changes in gene expression due to a non-lethal salt stress (100 mm NaCl) in the nhx1 plants were significantly different from the changes seen in wild-type plants. The nhx1 transcriptome was differentially affected when the plants were grown in the absence or presence of salt. In conclusion, in addition to the known role(s) of AtNHX1 on ion homeostasis, the vacuolar cation/proton antiporter plays a significant role in intracellular vesicular trafficking, protein targeting, and other cellular processes.
拟南芥液泡阳离子/质子逆向转运蛋白AtNHX1在耐盐性、离子稳态和发育过程中发挥着重要作用。我们利用AtNHX1的T-DNA插入突变体（nhx1植株）和Affymetrix ATH1 DNA芯片来评估转录谱的差异，并进一步阐明液泡阳离子/质子逆向转运蛋白的作用。本研究使用在土壤中生长成熟的植株，以模拟典型的生理生长条件。对未受盐胁迫的植株进行比较，发现许多转录本受到AtNHX1液泡逆向转运蛋白缺失的影响。此外，nhx1植株中由非致死性盐胁迫（100 mM NaCl）引起的基因表达变化与野生型植株中观察到的变化显著不同。当植株在无盐或有盐条件下生长时，nhx1转录组受到的影响存在差异。总之，除了AtNHX1在离子稳态方面的已知作用外，液泡阳离子/质子逆向转运蛋白在细胞内囊泡运输、蛋白质靶向和其他细胞过程中也发挥着重要作用。
