NIN-like protein 8 is a master regulator of nitrate-promoted seed germination in Arabidopsis

作者：Dawei Yan, Vanathy Easwaran, Vivian Chau, Masanori Okamoto, Matthew Ierullo, Mitsuhiro Kimura, Akira Endo, Ryoichi Yano, Asher Pasha, Yunchen Gong, Yong‐Mei Bi, Nicolas Provart, David S. Guttman, Anne Krapp, Steven J. Rothstein, Eiji Nambara · 发表于：Nature Communications · 年份：2016 · DOI：10.1038/ncomms13179 · 被引用次数：245 · 研究领域：Plant nutrient uptake and metabolism、Plant Stress Responses and Tolerance、Legume Nitrogen Fixing Symbiosis

Seeds respond to multiple different environmental stimuli that regulate germination. Nitrate stimulates germination in many plants but how it does so remains unclear. Here we show that the Arabidopsis NIN-like protein 8 (NLP8) is essential for nitrate-promoted seed germination. Seed germination in nlp8 loss-of-function mutants does not respond to nitrate. NLP8 functions even in a nitrate reductase-deficient mutant background, and the requirement for NLP8 is conserved among Arabidopsis accessions. NLP8 reduces abscisic acid levels in a nitrate-dependent manner and directly binds to the promoter of CYP707A2, encoding an abscisic acid catabolic enzyme. Genetic analysis shows that NLP8-mediated promotion of seed germination by nitrate requires CYP707A2. Finally, we show that NLP8 localizes to nuclei and unlike NLP7, does not appear to be activated by nitrate-dependent nuclear retention of NLP7, suggesting that seeds have a unique mechanism for nitrate signalling.