Division of Plant Biology, Bose Institute, Kolkata, India.
Department of Botany, Bethune College, Kolkata, India.
Sci Rep. 2019 Mar 29;9(1):5358. doi: 10.1038/s41598-019-41809-7.
Halophytes are rich sources of salt stress tolerance genes which have often been utilized for introduction of salt-tolerance character in salt-sensitive plants. In the present study, we overexpressed PcINO1 and PcIMT1 gene(s), earlier characterized in this laboratory from wild halophytic rice Porteresia coarctata, into IR64 indica rice either singly or in combination and assessed their role in conferring salt-tolerance. Homozygous T/T transgenic plants revealed that PcINO1 transformed transgenic rice lines exhibit significantly higher tolerance upto 200 mM or higher salt concentration with negligible compromise in their growth or other physiological parameters compared to the untransformed system grown without stress. The PcIMT1-lines or the double transgenic lines (DC1) having PcINO1 and PcIMT1 introgressed together, were less efficient in such respect. Comparison of inositol and/or pinitol pool in three types of transgenic plants suggests that plants whose inositol production remains uninterrupted under stress by the functional PcINO1 protein, showed normal growth as in the wild-type plants without stress. It is conceivable that inositol itself acts as a stress-ameliorator and/or as a switch for a number of other pathways important for imparting salt-tolerance. Such selective manipulation of the inositol metabolic pathway may be one of the ways to combat salt stress in plants.
盐生植物富含耐盐基因，这些基因常被用于向盐敏感植物中导入耐盐特性。在本研究中，我们分别或组合过表达了先前从野生盐生稻 Porteresia coarctata 中鉴定的 PcINO1 和 PcIMT1 基因到籼稻 IR64 中，并评估了它们在赋予耐盐性方面的作用。纯合 T/T 转基因植株表明，与未胁迫生长的非转化系统相比，转化 PcINO1 的转基因水稻品系在 200mM 或更高的盐浓度下表现出显著更高的耐受性，而生长或其他生理参数几乎没有受到影响。在这方面，PcIMT1 系或同时导入 PcINO1 和 PcIMT1 的双转基因系（DC1）效率较低。对三种转基因植物的肌醇和/或松醇池的比较表明，在应激条件下，功能正常的 PcINO1 蛋白使肌醇的产生不受干扰的植物，表现出与无应激野生型植物一样的正常生长。可以想象，肌醇本身可以作为一种应激缓解剂和/或作为许多其他对赋予耐盐性很重要的途径的开关。对肌醇代谢途径的这种选择性操纵可能是植物应对盐胁迫的方法之一。
