Scientists have uncovered a protein that plays a crucial role in sealing plant roots, thereby controlling the absorption of nutrients and water from the soil.
This discovery has the potential to aid in the development of resilient crops that require reduced water and chemical fertilizers.
The research, conducted by the University of Nottingham, goes deep into the identification of novel elements within the lignin barrier in plant roots and the specific functions of dirigent proteins (DPs) situated in the root endodermis. This helps in governing the regulation of water and nutrient uptake.
The study findings have been recently reported in Science.
Plant roots operate by drawing in essential mineral nutrients and water from the soil while maintaining a precise balance within the plant. This delicate control is managed by a specialized layer of root tissue known as the endodermis.
Within the endodermis lies a barrier, composed of lignin, the same substance found in wood. This impervious barrier creates a tight seal between cells, preventing the uncontrolled movement of materials into the root.
This seal ensures that the sole route for nutrients and water to enter the roots is through the endodermis cells, allowing for precise control over what enters and exits the plant through its roots. The research has identified fresh components of the lignin deposition process, with a specific focus on the role of dirigent proteins (DPs) found in the root endodermis.
These proteins work in concert with other established regulatory elements in the root to guide and organize the proper deposition of lignin within the endodermis, thereby enabling the plant to guarantee an optimal balance of nutrients from the soil.
With record temperatures being reached in parts of the world this year and erratic rainfall it is ever more important to understand the mechanisms of plants so we can future proof them to secure future food supplies.”
Dr Gabriel Castrillo, School of Biosciences
Castrillo added, “This research shows how plant roots regulate their uptake of water and nutrients through the deposition of lignin, which is regulated by DPs. Without these proteins, proper root sealing is not completed and the nutrient balance in the plant is compromised. We can use this knowledge to engineer plants to be able to grow with less water and chemical fertilizers.”
Gao, Y.-Q., et al. (2023). A dirigent protein complex directs lignin polymerization and assembly of the root diffusion barrier. Science. doi.org/10.1126/science.adi5032.