Sato Takeo, Maekawa Shugo, Konishi Mineko, Yoshioka Nozomi, Sasaki Yuki, Maeda Haruna, Ishida Tetsuya, Kato Yuki, Yamaguchi Junji, Yanagisawa Shuichi
Faculty of Science and Graduate School of Life Science, Hokkaido University, Kita-ku N10-W8, Sapporo 060-0810, Japan.
Biotechnology Research Center, The University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-8657, Japan.
Biochem Biophys Res Commun. 2017 Jan 29;483(1):380-386. doi: 10.1016/j.bbrc.2016.12.135. Epub 2016 Dec 23.
Nitrate modulates growth and development, functioning as a nutrient signal in plants. Although many changes in physiological processes in response to nitrate have been well characterized as nitrate responses, the molecular mechanisms underlying the nitrate response are not yet fully understood. Here, we show that NLP transcription factors, which are key regulators of the nitrate response, directly activate the nitrate-inducible expression of BT1 and BT2 encoding putative scaffold proteins with a plant-specific domain structure in Arabidopsis. Interestingly, the 35S promoter-driven expression of BT2 partially rescued growth inhibition caused by reductions in NLP activity in Arabidopsis. Furthermore, simultaneous disruption of BT1 and BT2 affected nitrate-dependent lateral root development. These results suggest that direct activation of BT1 and BT2 by NLP transcriptional activators is a key component of the molecular mechanism underlying the nitrate response in Arabidopsis.
硝酸盐可调节植物的生长和发育，作为一种营养信号发挥作用。尽管许多因硝酸盐而引起的生理过程变化已被很好地表征为硝酸盐响应，但硝酸盐响应背后的分子机制尚未完全了解。在这里，我们表明，作为硝酸盐响应的关键调节因子，NLP转录因子直接激活拟南芥中BT1和BT2的硝酸盐诱导表达，BT1和BT2编码具有植物特异性结构域结构的假定支架蛋白。有趣的是，BT2的35S启动子驱动表达部分挽救了拟南芥中因NLP活性降低而导致的生长抑制。此外，BT1和BT2的同时破坏影响了硝酸盐依赖的侧根发育。这些结果表明，NLP转录激活因子对BT1和BT2的直接激活是拟南芥硝酸盐响应分子机制的关键组成部分。
