April 2, 2013

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Nitrate activates NIN-like transcription factors through their N-terminal regions, and then the activated factors promote the expression of nitrogen assimilation-related genes and genes encoding regulatory proteins. Hence, NIN-like transcription factors are key factors for nitrogen response in higher plants. © Shuichi Yanagisawa

Plants take up nitrogen in soils and utilize it for biosynthesis of nitrogen-containing organic compounds for their growth. Nitrate, which is a major nitrogen source for land plants, functions as a key signal molecule that modulates the expression of a wide spectrum of genes, including not only nitrate assimilation-associated genes but also genes encoding regulatory proteins, and that regulate the nitrogen utilization mechanism and the growth rate.

A research team led by Associate Professor Shuichi Yanagisawa in the Laboratory of Plant Functional Biotechnology at the Biotechnology Research Center of the University of Tokyo demonstrated that NIN-like transcription factors play a central role in the regulation of nitrate-inducible events. Nitrate signaling activates NIN-like transcription factors, and the activated factors then promote the expression of a number of nitrate-inducible genes. Hence, NIN-like transcription factors function as key regulators of the nitrogen utilization mechanism.

As most land soils globally are nitrogen-deficient, huge amounts of nitrogen fertilizers are applied to fields to realize high crop yields. However, nitrogen fertilizers severely pollute the environment, especially the aquatic ecosystem. Identification of key factors in the regulation of the nitrate utilization mechanism will be of great value in plant biotechnology research, enabling the enhancement of the nitrogen utilization efficiency of crop plants to achieve increases in plant biomass and improve environmental protection.

Paper information

Mineko Konishi & Shuichi Yanagisawa, "Arabidopsis NIN-like transcription factors have a central role in nitrate signalling," Nature Communications Online Edition: March 19, 2013. DOI: 10.1038/ncomms2621.