超表达水稻MGD基因(OsMGD)烟草植株的耐低磷胁迫能力  

Tolerance of tobacco plans with OsMGD gene to low phosphorus stress

作　　者：史中惠[1,2] 王仕稳[2] 殷俐娜[2] 张梅娟[3] 邓西平[1,2] 

机构地区：[1]西北农林科技大学林学院,陕西杨凌712100 [2]西北农林科技大学黄土高原土壤侵蚀与旱地农业国家重点实验室,陕西杨凌712100 [3]西北农林科技大学生命科学学院,陕西杨凌712100

出　　处：《西北农林科技大学学报（自然科学版）》2013年第10期97-104,共8页Journal of Northwest A&F University(Natural Science Edition)

基　　金：中央高校基本科研业务费专项资金项目(QN2012048);高等学校学科创新引智计划项目(B12007)

摘　　要：【目的】研究超表达OsMGD基因烟草植株在低磷条件下的生长情况，为明确OsMGD基因对植物耐低磷胁迫的影响机理奠定基础。【方法】通过构建表达载体pGWB2-OsMGD和农杆菌介导的转化方法，获得超表达OsMGD基因烟草植株，用磷浓度为5 μmol/L的HS营养液对转基因烟草植株进行低磷处理后，研究转基因烟草植株MGD活性、脂质和脂肪酸含量、叶绿素含量、根系鲜质量、根冠比和磷含量的变化情况。【结果】超表达OsMGD基因烟草植株中MGD活性增加了1～3.5倍；在转基因烟草植株中，半乳糖脂（MGDG和DGDG）、磷脂和总脂肪酸含量均显著高于野生型植株，但是转基因烟草植株中的脂肪酸组分与野生型相比无显著差异。低磷处理后，转基因烟草植株的生长情况明显优于野生型植株，转基因烟草植株中叶绿素含量、根系鲜质量和根冠比均显著高于野生型；在正常和低磷条件下，转基因烟草植株中的磷含量与野生型相比无显著差异。【结论】超表达OsMGD基因能增加烟草植株的细胞膜脂含量，使植物体内累积大量半乳糖脂和磷脂，从而提高了烟草植株耐低磷胁迫的能力。【Objective】This research was to investigate the growth of transgenic tobacco with OsMGD under phosphorous deficiency.【Method】Tobacco plants with OsMGD gene were constructed through the construction of expression vector pGWB2-OsMGD and agrobacterium mediated transformation methods.After being treated with Hoagland nutrient solution （phosphorus concentration 5 μmol/L）,the changes of MGD activity,lipids and fatty acid contents,chlorophyll content,root fresh weight,root shoot ratio and phosphorus content in transgenic tobacco plants were investigated.【Result】MGD synthase activity of tobacco with overexpression OsMGD increased by 1-3.5 folds.The contents of galactolipids （MGDG and DGDG）,phospholipids and total fatty acids in transgenic tobaccos were significantly higher than that in wild type.But the fatty acid contents of all lipids were unchanged compared with wild type.After low phosphorus treatment,the transgenic tobacco growth was significantly better than wild type.The chlorophyll content,root fresh weight and the ratio of root to shoot in transgenic tobacco were significantly higher than wild type.Under the conditions of normal and low phosphorus,phosphorus contents in transgenic tobacco plants were not significantly different compared with wild type.【Conclusion】Overexpression OsMGD gene increased cell membrane lipid content of tobacco plant.The plant accumulated a large number of galactolipids and phospholipids, which improved the resistance of tobacco plant to low phosphorus stress.

关 键 词：单半乳糖甘油二酯(MGDG) 磷脂 低磷胁迫 烟草 

分 类 号：Q945.79[生物学—植物学]