Discipline of Marine Biotechnology and Ecology, CSIR- Central Salt and Marine Chemicals Research Institute, G.B. Road, Bhavnagar, 364 002, Gujarat, India.
Mar Biotechnol (NY). 2012 Dec;14(6):782-92. doi: 10.1007/s10126-012-9442-7. Epub 2012 May 26.
Salinity severely affects plant growth and development. Plants evolved various mechanisms to cope up stress both at molecular and cellular levels. Halophytes have developed better mechanism to alleviate the salt stress than glycophytes, and therefore, it is advantageous to study the role of different genes from halophytes. Salicornia brachiata is an extreme halophyte, which grows luxuriantly in the salty marshes in the coastal areas. Earlier, we have isolated SbASR-1 (abscisic acid stress ripening-1) gene from S. brachiata using cDNA subtractive hybridisation library. ASR-1 genes are abscisic acid (ABA) responsive, whose expression level increases under abiotic stresses, injury, during fruit ripening and in pollen grains. The SbASR-1 transcript showed up-regulation under salt stress conditions. The SbASR-1 protein contains 202 amino acids of 21.01-kDa molecular mass and has 79 amino acid long signatures of ABA/WDS gene family. It has a maximum identity (73 %) with Solanum chilense ASR-1 protein. The SbASR-1 has a large number of disorder-promoting amino acids, which make it an intrinsically disordered protein. The SbASR-1 gene was over-expressed under CaMV 35S promoter in tobacco plant to study its physiological functions under salt stress. T(0) transgenic tobacco seeds showed better germination and seedling growth as compared to wild type (Wt) in a salt stress condition. In the leaf tissues of transgenic lines, Na(+) and proline contents were significantly lower, as compared to Wt plant, under salt treatment, suggesting that transgenic plants are better adapted to salt stress.
盐度严重影响植物的生长和发育。植物在分子和细胞水平上进化出各种机制来应对压力。盐生植物比糖生植物发展出更好的机制来减轻盐胁迫，因此，研究盐生植物不同基因的作用是有利的。盐角草是一种极端盐生植物，在沿海地区的盐沼中茂盛生长。早些时候，我们使用 cDNA 消减杂交文库从盐角草中分离出 SbASR-1（脱落酸胁迫成熟-1）基因。ASR-1 基因对脱落酸（ABA）有反应，其表达水平在非生物胁迫、损伤、果实成熟和花粉粒中增加。SbASR-1 转录本在盐胁迫条件下表现出上调。SbASR-1 蛋白含有 21.01kDa 分子量的 202 个氨基酸，具有 ABA/WDS 基因家族 79 个氨基酸长的特征。它与 Solanum chilense ASR-1 蛋白具有最大的同一性（73%）。SbASR-1 具有大量促进无序的氨基酸，使其成为一种固有无序的蛋白质。在烟草植物中，SbASR-1 基因在 CaMV 35S 启动子下过表达，以研究其在盐胁迫下的生理功能。与野生型（Wt）相比，T(0)转基因烟草种子在盐胁迫条件下表现出更好的萌发和幼苗生长。在转基因系的叶片组织中，与 Wt 植物相比，盐处理下 Na(+)和脯氨酸含量显著降低，表明转基因植物对盐胁迫的适应性更好。
