低氮下拟南芥叶酰聚谷氨酸合成酶突变体atdfb根发育研究  

Root Development in Arabidopsis Folylpolyglutamate Synthetase Mutant adtfb under Low-nitrogen Condition

作　　者：孟红岩[1] 汪文华[1] 张春义[2] MENG Hong-yan;WANG Wen-hua;ZHANG Chun-yi(Fujian Institute of Subtropical Botany/Fujian Key Laboratory of Physiology and Biochemistry for Subtropical Plant,Xiamen 361006,Fujian China;Biotechnology Research Institute,Chinese Academy of Agricultural Sciences,Beijing 100081, China)

机构地区：[1]福建省亚热带植物研究所/福建省亚热带植物生理生化重点实验室,福建厦门361006 [2]中国农业科学院生物技术研究所,北京100081

出　　处：《亚热带植物科学》2018年第3期199-206,共8页Subtropical Plant Science

基　　金：国家自然科学基金项目(31800245;31601133);国家973计划项目(2013CB127003);厦门科技计划项目(3502Z20161234)

摘　　要：利用叶酰聚谷氨酸合成酶功能缺失突变体atdfb解析叶酸在拟南芥根发育过程中的生物学功能。纯合T-DNA插入功能缺失突变体atdfb在土壤培养条件下生长3周,与野生型表型无明显差异。在氮源充足的1/2MS培养基上,atdfb的主根显著短于野生型,互补植株的主根长度恢复到野生型水平,说明主根缩短的表型是由AtDFB基因功能缺失造成的。在1/2MS培养基生长11 d的突变体主根长度只有野生型的23%。在低氮条件下,突变体的生长发育几乎停滞,培养11 d的突变体主根长度只有野生型的4%;5-甲酰四氢叶酸(5-F-THF)可以恢复低氮条件下atdfb-3的表型,其主根长度、根毛长度及静止中心的细胞排列均得到恢复。进一步分析发现,低氮条件下培养少于3 d的atdfb-3补充充足的5-F-THF,3 d后能像野生型一样适应低氮环境。由此说明叶酸对拟南芥根部发育及对低氮环境的适应是必需的。T-DNA insertion mutant of folylpolyglutamate synthetase atdfb was used to explore the role of folates during root development in Arabidopsis.Phenotype of three-week-old atdfb seedlings was similar to the wild type,however,the mutant displayed shorter primary root than the wild type on 1/2MS,and phenotype of complemented seedling was recovered indicating that the shorten root phenotype was due to the loss function of AtDFB.Length of primary root of 11-day-old atdfb-3 seedlings was 23%of the wild type on 1/2MS medium that was nitrogen(N)-sufficient conditions.The development of atdfb-3 almost stagnated under low-N conditions,and the primary root length of 11-day-old atdfb-3 seedlings was only 4%of the wild type.Under low-N conditions,exogenous 5-formyl-tetrahydrofolate(5-F-THF)restored the phenotype of atdfb-3 to the wild type.With the application of 5-F-THF,the primary root length,root hair length and the quiescent center cell organization in atdfb-3 were recovered.This study indicated the necessity of folates in Arabidopsis root development and adapting to low-N condition.

关 键 词：拟南芥 突变体 叶酸 低氮 主根 

分 类 号：Q945.78[生物学—植物学]