论文部分内容阅读
植物根系如何响应环境因子变化是植物发育和营养吸收研究的重要科学问题。丙酮酸激酶OsPK1在根部的表达主要在根尖成熟区和根毛区,其表达水平变化有可能影响水稻对外源糖分的吸收。采用日本晴和水稻突变体ospk1,通过改变1/2 MS培养基中蔗糖含量,探索水稻幼苗对外源糖分的吸收和响应。通过GC-MS的方法检测了水稻幼苗叶片、叶鞘和根中蔗糖、葡萄糖、果糖和半乳糖的含量。发现根与培养基中糖分接触能明显提高幼苗中的糖含量。并且这些幼苗的根系长度大于那些不加蔗糖的培养基培养的幼苗,表明外源糖分被吸收后能促进根的伸长。OsPK1表达下调影响了糖代谢和外源糖分的吸收。半定量RT-PCR结果显示,幼苗根与糖分的直接接触明显上调根中OsPIP2;4,OsPIP2;5和OsTIP2;1三个水孔蛋白基因的表达。
How plant roots respond to changes in environmental factors is an important scientific issue in plant development and nutrient uptake studies. The expression of pyruvate kinase OsPK1 in the root mainly occurs in the apical mature and root hairy areas, and its expression level may affect the absorption of exogenous sugars in rice. By using Nipponbare and rice mutant ospk1, the sucrose content of 1/2 MS medium was changed to explore the absorption and response of rice seedlings to exogenous sugars. The contents of sucrose, glucose, fructose and galactose in leaves, sheaths and roots of rice seedlings were determined by GC-MS. The results showed that the root and the sugar in the medium can significantly improve the sugar content of seedlings. And the root length of these seedlings was greater than those of the seedlings cultured in medium without sucrose, indicating that the exogenous sugar can promote root elongation after being absorbed. Down-regulation of OsPK1 affected glucose metabolism and the absorption of exogenous sugars. The results of semi-quantitative RT-PCR showed that the direct contact of seedling root and sugar obviously up-regulated the expression of three aquaporin genes of OsPIP2; 4, OsPIP2; 5 and OsTIP2; 1.