中国农业科学Issue(20)：3989-3997,9.DOI:10.3864/j.issn.0578-1752.2015.20.001
谷子转录因子SiNF-YA6的过表达提高转基因植株对低氮胁迫的抗性
Overexpression of a Transcription Factor GeneSiNF-YA6 from Millet (Setaria italica) Enhanced the Resistance of Transgenic Plants to Nitrogen Starvation
摘要
Abstract
Objective]Nuclear transcription factor Y (NF-Y) belongs to a transcription factor gene family widely existing in eukaryotic. NF-Y-like transcription factors are involved in the process of gene expression regulation of plant growth and development and stress responses. So far, it is never been reported that NF-Y-like transcription factors are involved in plant resistance to low nitrogen stress. In this study, a NF-Y-like transcription factor geneSiNF-YA6 was isolated from millet, and its characteristics and biological function were identified.[Method]A NF-Y-like transcription factor geneSiNF-YA6 highly up-regulated by low nitrogen stress was selected from the results of transcriptome sequencing of millet treated by low nitrogen. DNAMAN and MEGA6.0 software were used to make the phylogenetic tree of NF-YA6. The Real-time PCR was used to analyze expression patterns of SiNF-YA6 under different treatments. SiNF-YA6 was transformed intoArabidopsis protoplast to observe its subcellular localization. SiNF-YA6 was overexpressed inArabidopsis to identify gene function.[Result]SiNF-YA6 is 714 bp in length and encoding 237 amino acids. SiNF-YA6 contains a CBF conservative domain with 62 amino acids. Phylogenetic tree analysis showed that NF-YA was fell into 6 classes, and SiNF-YA6 belongs to the fifth class. SiNF-YA6 was the highest homology with a rice NF-YA protein (Os03g07880) (77.4%). Expression pattern analysis showed thatNF-YA6 was induced by low nitrogen stress, and its expression reach peak after treatment for 5 d that raised about 5 times compared with the expression level at the beginning of treatment. While transcription ofSiNF-YA6 under high salt, drought, ABA treatment also showed a trend of increasing.SiNF-YA6 under SA and GA treatments was no obvious different. Tissue specific expression analysis showed thatSiNF-YA6 mainly expressed in millet roots. Subcellular localization indicated that SiNF-YA6 was mainly located on the plasmalemma and nucleus in plant cell. Results of low nitrogen stress resistance test showed that the main root length and root surface areaofSiNF-YA6 transgenicArabidopsis were significantly higher than in wild typeArabidopsis, and the fresh weight of transgenic plants was also significantly greater than the wild type plants (P<0.01) under low nitrogen stress (total nitrogen content of 1 mmol·L-1), and the growthofSiNF-YA6 transgenic Arabidopsis showed no obvious difference with wild-typeArabidopsis under SA and GA treatments. Those results indicated that overexpression ofSiNF-YA6 gene significantly enhanced transgenic plants resistance to low nitrogen stress. The downstream genes, including some nitrogen transporter genes (NRT2.1 andNRT2.4), were up-regulated inSiNF-YA6 transgenicArabidopsis. However, SiNF-YA6 transgenicArabidopsis showed no obvious difference with wild-typeArabidopsis under high salt and drought stresses.[Conclusion]Overexpression ofSiNF-YA6 enhanced transgenic plants tolerance to low nitrogen stress by up-regulated expression of several nitrogen transporter genes, which will give new candidate for improvement of the nitrogen use efficiency in crops.关键词
谷子(Setaria italica)/核转录因子A亚基/功能分析/低氮胁迫Key words
foxtail millet (Setaria italica)/NF-YA transcription factor/function analysis/low nitrogen stress引用本文复制引用
方广宁,贾冠清,陈明,闵东红,胡利芹,王二辉,薛飞洋,马有志,徐兆师,李连城,周永斌,刁现民..谷子转录因子SiNF-YA6的过表达提高转基因植株对低氮胁迫的抗性[J].中国农业科学,2015,(20):3989-3997,9.基金项目
国家转基因新品种生物培育重大专项（2014ZX08002-002）、国家转基因生物新品种培育重大专项（2014ZX08002-003B）、陕西省农业科技攻关项目 （）
