Institute of Crop Science, NARO

New mechanism of abscisic acid signaling cascade

Towards achieving efficiency of crops that prevent pre-harvest sprouting

A collaborative research of NARO has revealed a new mechanism of the plant hormone abscisic acid signaling cascade. This result is expected to facilitate the development of efficient strategy to address the prevention of pre-harvest sprouting during agricultural crop production.


Overview

Plants accumulate the plant hormone abscisic acid (ABA) when exposed to environmental stresses such as drought and low temperature. ABA is known to regulate stomatal closure and regulating the expression level of various genes in response to the environmental stresses. Seed dormancy is one of the strategy to prevent the seeds from germinating under unfavorable environmental conditions. ABA also plays a significant role in seed dormancy.

A research collaboration of NARO has revealed new functional mechanisms of ABA signaling on seed dormancy and germination using the model plant Arabidopsis thaliana. Until now, it has been thought that a mechanism via ABA receptor was necessary for ABA to function at the time of germination. In addition, a new mechanism involving complex formation of AHG1 PP2C phosphatase with heme-bound DOG1 protein, has been discovered to play a significant role in seed dormancy.

AHG1 and DOG1 genes are also present in important crops such as rice, wheat and barley. Since pre-harvest sprouting which is a major problem in the cultivation of wheat and barley is deeply involved in seed dormancy, regulating the functions of AHG1 protein and/or DOG1 protein as shown in this study, in addition to proteins acting in a mechanism mediated by ABA receptors, is expected to be useful for addressing agricultural crops that prevent pre-harvest sprouting.

The results are published in the online edition of the international scientific journal "Nature Communications" (dated June 6, 2018).


Publication

Noriyuki Nishimura, Wataru Tsuchiya, James J. Moresco, Yuki Hayashi, Kouji Satoh, Nahomi Kaiwa, Tomoko Irisa, Toshinori Kinoshita, Julian I. Schroeder, John R. Yates, III, Takashi Hirayama & Toshimasa Yamazaki. "Control of seed dormancy and germination by DOG1-AHG1 PP2C phosphatase complex via binding to heme", Nature Communications (doi: 10.1038/s41467-018-04437-9 published online on June 6, 2018)


For Inquiries

Contact: http://www.naro.affrc.go.jp/english/inquiry/index.html


Reference Information

aba-1

aba-2

aba-3

aba-4

Corporate Number 7050005005207