Despite being largely unchanged for over 450 million years, a family of “mischievous” proteins that are present in all land plants is responsible for a wide range of plant activities.
DELLA proteins control how much a plant develops, when germination takes place, and how plants respond to hazards like drought and disease, according to recent results published in Nature Plants and New Phytologist.
The capability of DELLA proteins to interact with numerous distinct transcription factors, which are the proteins in charge of decoding DNA, rather than their propensity to mutate over time, is the key.
Similar to the selective breeding techniques that kicked off the Green Revolution in the 1960s, understanding the processes underlying the functions of DELLA proteins can help crop scientists create new plant proteins to produce crops with improved resilience and higher yields.
The DELLA proteins in many of the initial Green Revolution breeding strains themselves had altered functions.
Researchers from the School of Biosciences at the University of Birmingham in the UK and the Institute of Molecular and Cellular Biology of Plants (IBMCP) in Spain conducted the studies.
By understanding how the activity of these proteins changed over time, we can understand more about how it might be possible to tweak and engineer plants that are better adapted to our changing environment.”
Dr Juliet Coates, Associate Professor, Plant Molecular Genetics, School of Biosciences, University of Birmingham
The researchers examined mosses and liverworts, the plants that are most likely to mimic those early pioneering species, to learn how DELLA proteins changed over the 450 million years since plants first appeared on Earth.
Scientists are already aware that gibberellin, a plant hormone, controls the amounts of DELLA proteins found in modern flowering plants, changing them in reaction to environmental factors.
They were able to show in new studies that the DELLA proteins’ range was just as complex in early plants as opposed to having only basic interactions, and that these interactions were also distinct from those observed in modern crops like wheat or rice.
Furthermore, these relationships were available regardless of the presence or absence of the gibberellin hormone. Additionally, they were able to pinpoint a core set of interactions that were shared by all DELLA proteins and related to defense and responses to reduced oxygen levels.
A very important area of work in gibberellin biotechnology is trying to obtain varieties or chemical compounds that allow us to achieve the desired goals without the side effects. Understanding how DELLA proteins have evolved in nature over millions of years helps us to design new strategies to generate new DELLA variants with the desired functions.”
Dr Miguel Ángel Blázquez, Study Co-Author and Principal Investigator, Institute of Molecular and Cellular Biology of Plants
Briones-Moreno, A., et al. (2023). DELLA functions evolved by rewiring of associated transcriptional networks. Nature Plants. doi.org/10.1038/s41477-023-01372-6