Adabnejad Hamed, Kavousi Hamid Reza, Hamidi Hadi, Tavassolian Iraj
Department of Biotechnology, Faculty of Agriculture, Shahid Bahonar University ofKerman, Kerman, Iran.
Department of Horticulture, Faculty of Agriculture, Shahid Bahonar University of Kerman, Kerman, Iran.
Mol Biol Res Commun. 2015 Sep;4(3):133-142.
Sodium/proton exchangers (NHX) are key players in plant responses to salinity and have a central role in establishing ion homeostasis. NHXs can be localized in tonoplast or plasma membranes, where they exchange sodium ions for protons, resulting in the removal of ions from the cytosol into vacuole or extracellular spaces. In the present study, the expression pattern of the gene encoding Na+/H+ antiporter in the vacuolarmembrane (NHX1 gene) in (Kallar grass) was measured by a semi- quantitative RT-PCR method under different treatments of NaCl and CdCl2. Results indicated that NaCl positively affected expression levels of NHX1, and that the amount of NHX1 mRNA increased in conjunction with the rise of salinity pressure, This finding suggests that vacuolar Na+/H+ antiporter might play an important role in the salt tolerance ability of kallar grass. The results also showed that cadmium exposure significantly modulated the mRNA expression of the NHX1 gene, suggesting that cadmium exposure disturbed Na+ homeostasis across the tonoplast and decreased the salt tolerance ability of kallar grass.
钠/质子交换体（NHX）是植物对盐胁迫响应的关键因子，在建立离子稳态中起核心作用。NHX可定位于液泡膜或质膜，在那里它们将钠离子与质子进行交换，从而导致离子从细胞质溶胶转运至液泡或细胞外空间。在本研究中，采用半定量RT-PCR方法测定了在不同NaCl和CdCl₂处理下，（芦苇）液泡膜上编码Na⁺/H⁺逆向转运蛋白的基因（NHX1基因）的表达模式。结果表明，NaCl对NHX1的表达水平有正向影响，且NHX-1 mRNA的量随着盐胁迫压力的升高而增加。这一发现表明，液泡Na⁺/H⁺逆向转运蛋白可能在芦苇的耐盐能力中发挥重要作用。结果还表明，镉暴露显著调节了NHX1基因的mRNA表达，表明镉暴露扰乱了液泡膜两侧的Na⁺稳态，并降低了芦苇的耐盐能力。
