| 摘要: |
| 为了研究苋菜亚硝酸还原酶基因NiR对不同铵硝配比及红蓝复合光配比调控氮代谢的响应，采用RT-PCR 结合qRT-PCR的方法从大红苋菜中克隆出一个NiR基因，命名为AtrNiR(GenBank登录号:MT374155)，对其相对表达量进行分析，并测定材料NiR酶活性。结果表明:1)苋菜AtrNiR基因含一个1 785 bp开放阅读框，编码594个氨基酸；2)生物信息学分析表明，苋菜AtrNiR的蛋白分子式为C2937H4692N828O873S28，相对分子质量为66.47 ku，AtrNiR为亲水性较强的蛋白；3)系统进化树分析表明，苋菜AtrNiR蛋白序列与甜菜、藜麦和菠菜的NiR蛋白同源性最高，具有类似的功能；4)苋菜幼苗NiR酶含量分析表明，不同铵硝配比处理3 d时，硝态氮(NH4+-N)与铵态氮(NO3--N)摩尔比值为10∶0时NiR酶活性最高，处理6 d时，NH4+-N与NO3--N摩尔比值为3∶7时NiR酶活性最高；不同红蓝光配比处理3 d时，红光(Red)∶蓝光(Blue)=2∶8处理下NiR酶活性最高，可见，NO3--N和蓝光能提高苋菜幼苗NiR酶活性；5)qRT-PCR分析结果表明，不同铵硝配比处理3 d时，NH4+-N与NO3--N摩尔比值为5∶5时AtrNiR表达量最高；不同红蓝复合光配比处理3 d时，R∶B=2∶8处理下AtrNiR表达量最高。研究表明，适宜比例的氮素和红蓝复合光能提高AtrNiR转录水平，改善苋菜幼苗的氮代谢，为优质苋菜工厂化生产提供理论支撑。 |
| 关键词: 苋菜 亚硝酸还原酶 酶活性 基因克隆 表达分析 |
| DOI：10.11841/j.issn.1007-4333.2021.08.07 |
| 投稿时间：2020-10-19 |
| 基金项目:福建省自然科学基金项目(2018J01700)；福建农林大学科技创新专项基金项目(CXZX2017174,CXZX2016118,CXZX201719) |
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| Effects of nitrogen and red and blue light on NiR enzyme activity and gene expression in Amaranthus tricolor L. seedlings |
|
CHEN He,WANG Le,ZHAO Chunli,XIAO Fang,ZHEN Youfeng,LIU Shengcai
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| (Institute of Horticultural Plant Bioengineering, Fujian Agriculture and Forestry University, Fuzhou 350002, China) |
| Abstract: |
| To study the response of amaranth NiR gene to nitrogen metabolism regulated by different ammonium and nitrate ratio and red and blue composite light ratio, a NiR gene named AtrNiR(GenBank Accession no. MT374155)was cloned from Amaranth by RT-PCR combined with qRT-PCR, its relative expression was analyzed and the activity of NiR enzyme was measured. The results showed that 1)The AtrNiR gene contained an open reading frame of 1 785 bp in length, which encoded 595 amino acids; 2)Bioinformatics analysis indicated that the protein molecular formula of AtrNiR is C2937H4692N828O873S28, with a relative molecular mass of 66. 47 ku. It is a hydrophilic protein; 3)Phylogenetic tree analysis showed that the AtrNiR protein sequence has the highest homology with that of Beta vulgaris L. , Chenopodium quinoa Willd. and Spinacia oleracea L. and has similar function; 4)The analysis of nitrite reductase content in Amaranth seedlings showed that the nitrite reductase activity is the highest when the molar ratio of NH4+-N to NO3--N was 10∶0 at different ammonium nitrate ratios for 3 days. When the molar ratio of NH4+-N to NO3--N was 3∶7, the nitrite reductase activity is the highest for 6 days. The nitrite reductase activity was the highest under the treatment of R∶B=2∶8 with different red and blue light ratios for 3 days. It can be seen that NO3 - N and blue light can improve the NiR enzyme activity of amaranth seedlings; 5)qRT-PCR analysis showed that AtrNiR expression was highest when the molar ratio of NH4+-n to NO3--N is 5∶5 at different ammonium nitrate ratios for 3 days. The AtrNiR expression was the highest under the treatment of R∶B=2∶8 with different red and blue light ratios for 3 days. The results suggested that the nitrogen absorption and nitrogen metabolism of Amaranth, seedlings were improved by the appropriate ratio of nitrogen and red and blue combined light energy. The study provides theoretical support for the factory production of quality amaranth. |
| Key words: Amaranthus tricolor L. nitrite reductase enzyme activity gene clone expression analysis |
