UNAM Researchers Investigate LEA Proteins as a Critical Survival Mechanism for Seeds Facing Drought

A dedicated research team at the National Autonomous University of Mexico (UNAM) is currently conducting in-depth studies into the molecular mechanisms that sustain the viability of plant seeds amidst the growing threat of global drought. The focal point of this scientific inquiry is a group of molecules known as Late Embryogenesis Abundant (LEA) proteins. These specific proteins are observed to accumulate in significant quantities within seeds as they undergo severe desiccation, losing up to 90% of their internal moisture content. By understanding how these proteins function, scientists hope to unlock the secrets of plant resilience in increasingly arid environments.

LEA proteins are scientifically categorized by their highly flexible and intrinsically disordered structural characteristics. These unique properties play a decisive role in the survival process by allowing the plant embryo to enter a vitrified, or glass-like, state. This transition is vital because it stabilizes the internal cellular environment, ensuring that the seed remains alive and capable of germinating even after long periods of dormancy. Dr. Alejandra Covarrubias Robles, leading a team at the UNAM Institute of Biotechnology (IBt), has provided experimental evidence confirming the essential nature of these molecules. Her research demonstrated that genetic mutations affecting these flexible proteins resulted in a drastic reduction in seed longevity and a significant acceleration of the aging process, thereby proving their protective function.

The scope of these investigations involved the use of Arabidopsis thaliana, a common model organism in plant biology, as well as various legume species. This diverse selection of test subjects underscores the potential for these findings to be applied across a wide range of agricultural sectors. The data gathered from these experiments offers promising new avenues for biotechnology, specifically in the development of genetically enhanced crops that can withstand extreme dehydration. These LEA proteins belong to a broader class of molecules called hydrophilins, which are notably rich in the amino acid glycine. This chemical composition allows them to maintain a flexible shape in water-based solutions, a trait commonly found in the seeds and pollen of land plants that must survive stages of dehydration and cryptobiosis.

One of the most fascinating aspects of LEA proteins is how they differ from traditional molecular chaperones. Unlike chaperones, LEA proteins do not require adenosine triphosphate (ATP) to perform their protective duties, nor do they focus on restoring the original shape of other proteins after they have been dehydrated. The implications of this research extend far beyond the field of botany; in vitro studies have shown that LEA proteins are capable of stabilizing other sensitive protein structures. This suggests that they could eventually be utilized in medical science for the preservation of animal embryos or human cells during complex clinical procedures. Furthermore, the presence of these proteins and their dehydrin sub-families, specifically the D-11 group, has been detected in various plant and animal tissues, indicating that these survival mechanisms are evolutionarily ancient.

In the current era of climate instability, ensuring global food security has become a priority for scientists and policymakers alike. Gaining a comprehensive understanding of the biological triggers that allow seeds to enter and survive dormancy is a fundamental step toward this goal. The work being carried out at UNAM serves as a vital foundation for the development of innovative plant breeding strategies aimed at increasing the adaptive capacity of crops to shifting weather patterns. By successfully integrating this biotechnological knowledge, the international community may be able to secure more robust and long-term storage for global seed banks, which is an essential component for the sustainability of agriculture in an unpredictable future.