The NIN-like protein 5 (ZmNLP5) transcription factor is involved in modulating the nitrogen response in maize
The NIN-like protein 5 (ZmNLP5) transcription factor is involved in modulating the nitrogen response in maize
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DOI：
10.1111/tpj.14628
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发表时间：
2020-01-04
期刊：
影响因子：
7.2
通讯作者：
Zhao, Han
中科院分区：
文献类型：
--
作者：
Ge, Min;Wang, Yuancong;Zhao, Han
玉米对补氮有显著的生长和产量响应。在这里，我们报道了玉米N-样蛋白ZmNLP5作为与N代谢相关的分子网络中的中心枢纽的功能表征。ZmNLP5主要在根和维管组织中表达和积累，对硝酸盐处理反应迅速。在氮素供应有限的情况下，与野生型（WT）相比，zmnlp5突变体幼苗在根组织中积累的硝酸盐和亚硝酸盐以及在茎部组织中积累的铵态氮较少。zmnlp5突变体植株在穗叶和籽粒中积累的氮量低于WT植株。此外，与ZmNLP5突变体相比，携带转基因ZmNLP5 cDNA片段的突变体显著增加了根组织中硝酸盐的含量。在zmnlp5突变植株中，丧失zmnlp5功能导致大量与N信号和代谢有关的基因表达发生变化。我们进一步发现，ZmNLP5通过与该基因5 ' UTR上的硝酸盐响应顺式元件结合，直接调控亚硝酸盐还原酶1.1 （ZmNIR1.1）的表达。有趣的是，与ZmNLP5突变株相似，Mo17中ZmNLP5等位基因的自然功能缺失导致穗叶和籽粒的氮积累减少。研究结果表明，ZmNLP5参与了玉米植株对氮的响应调控。
Maize exhibits marked growth and yield response to supplemental nitrogen (N). Here, we report the functional characterization of a maize NIN-like protein ZmNLP5 as a central hub in a molecular network associated with N metabolism. Predominantly expressed and accumulated in roots and vascular tissues, ZmNLP5 was shown to rapidly respond to nitrate treatment. Under limited N supply, compared with that of wild-type (WT) seedlings, the zmnlp5 mutant seedlings accumulated less nitrate and nitrite in the root tissues and ammonium in the shoot tissues. The zmnlp5 mutant plants accumulated less nitrogen than the WT plants in the ear leaves and seed kernels. Furthermore, the mutants carrying the transgenic ZmNLP5 cDNA fragment significantly increased the nitrate content in the root tissues compared with that of the zmnlp5 mutants. In the zmnlp5 mutant plants, loss of the ZmNLP5 function led to changes in expression for a significant number of genes involved in N signalling and metabolism. We further show that ZmNLP5 directly regulates the expression of nitrite reductase 1.1 (ZmNIR1.1) by binding to the nitrate-responsive cis-element at the 5 ' UTR of the gene. Interestingly, a natural loss-of-function allele of ZmNLP5 in Mo17 conferred less N accumulation in the ear leaves and seed kernels resembling that of the zmnlp5 mutant plants. Our findings show that ZmNLP5 is involved in mediating the plant response to N in maize.