Press release written by the Institute of Transformative Bio-Molecules (ITbM), ºÚÁϳԹÏÍø, and .
Breakthrough reveals a new way plants perceive hydrogen peroxide, offering new insights for crop protection and plant immunity
Researchers at the Institute of Transformative Bio-Molecules (WPI-ITbM), ºÚÁϳԹÏÍø, together with collaborators from RIKEN Center for Sustainable Resource Science (RIKEN CSRS) and The University of Osaka, have uncovered a previously unknown mechanism by which plants detect hydrogen peroxide (H?O?), a key signaling molecule involved in stress responses and immunity. Published in Nature Communications, the study reveals that plants rely on a copper-dependent sensing system, rather than the previously assumed cysteine-based mechanism, to perceive reactive oxygen species (ROS).
This work reshapes our understanding of how plants respond to environmental stress and pathogens, and may pave the way for improving crop resilience. Quinones and hydrogen peroxide play a central role in plant responses to pathogens and environmental stress, and understanding how plants perceive these molecules could inform strategies to enhance crop protection and stress tolerance.
How plants detect redox-related molecules in their environment
As sessile organisms, plants constantly monitor their environment using specialized receptors on the surface of their cells. Among these, a class known as leucine-rich repeat receptor-like kinases can sense a wide range of stimuli. One such receptor, CARD1 (also called HPCA1), was previously shown to detect both quinones and ROS such as H?O?. However, how a single receptor distinguishes between these chemically distinct signals remained unclear.
The research team discovered that CARD1 contains a copper ion bound to a cluster of histidine residues on its surface. This copper site plays a critical role in detecting H?O?.
Surprisingly, cysteine residues ¡ª previously thought to be essential for H2O2 sensing ¡ª are not required for signal perception. Instead, the CARD1 receptor uses copper to detect H?O? through redox chemistry.
¡°The results showed that when the copper-binding site is disrupted, plants lose their ability to respond to H?O? signals,¡± said Anuphon Laohavisit, lead author and designated associate professor at the WPI-ITbM. ¡°In contrast, mutations in cysteine residues had little effect on signaling, indicating that their primary role is structural rather than signaling.¡±
Through computational approaches, the team suggests that ROS sensing by CARD1 could occur through oxidation of copper (Cu? to Cu??) at the receptor surface. Such a redox change may either directly trigger signaling or generate secondary molecules that activate downstream responses. It is likely that a separate pathway exists for quinone perception and remains to be identified.
Conclusion and future perspective
The researchers provide the first structural evidence of a metal ion¨Cbased sensing mechanism in plant plasma membrane receptors, reshaping our understanding of ROS perception in plants and paving the way for exploring metal-based ROS signaling mechanisms across biology.
Paper information:
Nobuaki Ishihama, Yohta Fukuda, Yumiko Shirano, Kazuhiro J. Fujimoto, Kaori Takizawa, Ryoko Hiroyama, Hiroki Ito, Mayumi Nishimura, Takeshi Yanai, Tsuyoshi Inoue, Ken Shirasu and Anuphon Laohavisit. (2026). ¡°A copper-dependent, redox-based hydrogen peroxide perception in plants,¡± Nature Communications, DOI: .
Funding information:
This work was supported by JSPS KAKENHI (grant number JP22H00364), JSPS KAKENHI (grant number JP24K01718), JST GteX program (grant JPMJGX23B2), JST FOREST program (grant JPMJFR220G), MEXT Promotion of Development of a Joint Usage/Research System Project: Coalition of Universities for Research Excellence Program (CURE) (grant JPMXP1323015482), MEXT Project for promoting public utilization of advanced research infrastructure: Program for supporting construction of core facilities (grant number JPMXS04411024), RIKEN TRIP initiative Field Omits, and the Mitsubishi Foundation.
Expert contact:
Anuphon Laohavisit
Institute of Transformative Bio-Molecules (WPI-ITbM), ºÚÁϳԹÏÍø
laohavisit.anuphon.f2@f.mail.nagoya-u.ac.jp
Media contact:
Samuel Jacob
Institute of Transformative Bio-Molecules (WPI-ITbM), ºÚÁϳԹÏÍø
jacob.samuel.isaac.j8@f.mail.nagoya-u.ac.jp
Top image:
Researchers have uncovered a previously unknown mechanism by which plants detect hydrogen peroxide (H?O?), a key signaling molecule involved in stress responses and immunity. Credit: Issey Takahashi (CC BY)
