IISER Pune Research Sheds Light on Plant Recovery Mechanisms After Injury
A groundbreaking study conducted by researchers at the Indian Institute of Science Education and Research (IISER) in Pune has unveiled the critical role of autophagy in facilitating the recovery of plants from physical injuries. Published in the prestigious Proceedings of the National Academy of Sciences (PNAS) journal on January 30, this research provides new insights into the molecular processes that enable leaves to regenerate roots after being cut.
Key Findings on Autophagy and Stress Reduction
The study, led by PhD student Akansha Gangulya under the guidance of Professor Kalika Prasad, discovered that autophagy—a cellular clean-up process—significantly reduces stress levels at the site of injury in plants. This reduction in stress is crucial as it allows for the formation of stem cells, which in turn activate the regeneration of roots from the cut ends of leaves. The researchers identified specific autophagy genes, namely the ATG8F and ATG8H isoforms, as being directly involved in this root regeneration process.
Understanding the Molecular Basis of Regeneration
In an interview with The Indian Express, Professor Prasad elaborated on the study's objectives, highlighting the long-standing curiosity about how plants can regrow so effectively after being clipped. He explained that when a plant is injured, there is an immediate accumulation of stress at the wound site, manifested through stress signaling molecules like reactive oxygen species (ROS). These free radicals can be harmful if not controlled, and the study aimed to understand how plant cells manage this stress.
The research team found that autophagy is activated within hours of injury, helping to clear damaged cell parts and prevent debris buildup. This process is essential for lowering stress levels, which then allows stem cell regulators to emerge and initiate healing and regeneration. Further experiments revealed that PLETHORA proteins, specifically PLT7 and PLT3, regulate the expression of ATG8F and ATG8H, respectively, indicating a plant-specific regulatory module for autophagy during regeneration.
Implications and Broader Significance
Professor Prasad emphasized the fascinating parallels between plants and animals, noting that both use ROS as early wound signals to activate autophagy for tissue regrowth. However, plants uniquely employ PLETHORA proteins to precisely guide this system. The study uncovered a previously unrecognized PLETHORA–autophagy–ROS regulatory module, offering new perspectives on regeneration mechanisms in plants.
The research utilized advanced methods such as cell biology imaging and genetic mutation, with contributions from undergraduate students Aabha Humnabadkar and Komal Gautam, as well as collaborators from the Netherlands, China, and Germany who provided new research reagents. This collaborative effort underscores the global relevance of the findings and their potential applications in agriculture and biotechnology.
Overall, the IISER Pune study not only advances our understanding of plant biology but also highlights the intricate cellular processes that enable resilience and recovery in the natural world.
