Chonnam National University scientists discover a molecular switch that protects crops from freezing cold

The onset of sudden cold spells can threaten plant survival, especially during early growth phases. But how do plants detect low temperatures fast enough to initiate life-saving changes? Researchers at Chonnam National University have identified a hidden molecular “off-switch” that quickly reprograms root development to withstand the adverse cold conditions.

This paper was made available online on 23 September 2025 and was published in Volume 67, Issue 11 of Journal of Integrative Plant Biology on 1 November, 2025. The study was led by Professor Jungmook Kim, Department of Bioenergy Science and Technology at Chonnam National University, working with researchers Uyen Thu Nguyen, Na Young Kang, and Dr. Dong Wook Lee, also from CNU.

The team discovered that cold stress triggers the rapid degradation of auxin/indole acetic acid (Aux/IAA) proteins, which normally suppress growth-related gene activation. Once these repressors break down, key regulators ARF7 and ARF19 are released, enabling them to activate cytokinin response factor 3 (CRF3), a master regulator that reshapes root architecture to cope with cold conditions.

“Cold stress doesn’t simply slow plant growth—it actively rewires hormone signaling to adapt root development,” says Prof. Kim.

The study also reveals that cold conditions activate cytokinin signaling to induce CRF2, which works together with CRF3. The two genes act as integrators, combining environmental cues with internal hormone signals to fine-tune lateral root initiation under stress. This also established that auxin and cytokinin pathways converge at CRFs, forming a unified cold-response module.

“Plants survive because they integrate external stress with internal developmental programs,” Prof. Kim added. “We have identified one of the key switches enabling that integration.”

The findings highlight opportunities to protect crops from rising climate instability. By enhancing CRF2/CRF3 signaling or stabilizing ARF activity via targeted degradation of Aux/IAAs, scientists could develop crops that maintain stable root growth in cold soils. Such varieties would improve early-season growth establishment, increase nutrient uptake efficiency, and support sustainable agriculture with reduced fertilizer use. The study also highlights the potential for the development of synthetic molecules or biostimulants that could protect seedlings during unexpected spells of extreme cold.

Over the next decade, this molecular pathway may help enable crop cultivation in harsher climates, and serve as a foundation for precision breeding and CRISPR-based engineering of climate-resilient crops.

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Reference
DOI: https://doi.org/10.1111/jipb.70039

About the institute
Chonnam National University (CNU), established in 1952 as Korea’s first national university, is a leading institution of higher learning located in Gwangju. Building on its founding commitment to cultivating leaders of integrity and professional excellence, CNU contributes to national development and global progress through the pursuit of knowledge, ethical responsibility, and inclusive excellence. Guided by the core motto “Truth, Creativity, and Service,” the university advances research, education, and public engagement that strengthen resilient societies, foster sustainable development, and promote the well-being of future generations. As a trusted partner in the global community, CNU remains dedicated to addressing complex challenges in an increasingly interconnected world.

Website: https://global.jnu.ac.kr/jnumain_en.aspx

About Professor Jungmook Kim from Chonnam National University, South Korea
Professor Jungmook Kim is an Emeritus Professor of the Department of Bioenergy Science and Technology and Distinguished Research Professor, The CNU-Academy, at Chonnam National University, Korea. His group investigates how plants adapt to cold temperatures by integrating environmental stress signals with internal hormone networks, and how small molecules, including signaling peptides, modulate plant growth and development under stress. Before coming to Chonnam National University, he completed the Postdoctoral training at Steve Mayfield’s lab at The Scripps Research Institute and at Sakis Theologis’s lab at PGEC/UC-Berkeley. Prof. Kim had earned his PhD in Biochemistry and Biophysics from Texas A&M University in 1993.