Epigenetics: how the ‘dark matter of biology’ can fight plant diseases
Researchers have identified how DNA methylation controls heritable disease resistance in plants, which could prove beneficial in agriculture.
Researchers at the University of Sheffield have studied how plants are able to epigenetically pass on resistance to their offspring in order to strengthen their immune system against pests and diseases.
The study, published in eLife, was led by Professor Jurriaan Ton, at the University’s P3 Plant Production and Protection Centre. It is the first to identify specific DNA methylation loci that controls epigentically controlled disease resistance.
The researchers mentioned how findings from this study could provide conclusive evidence that selected DNA loci with reduced methylation have the ability to pass on disease resistance to following generations. This inheritance occurs epigenetically, meaning that it is not caused by changes in DNA sequence.
Working in collaboration with researchers from the PSL University in Paris, France, the Technical University of Munich, Germany, and La Trobe University, Australia, the findings of the study are a significant step forward in providing new evidence to the long-disputed theory that organisms are capable of inheriting complex traits independently of changes in DNA methylation.
The study identified specific loci in the centre of the plant’s chromosome that control the sensitivity of defence genes across the genome of the plant. The loci were found to control quantitative disease resistance against downy mildew – a pathogen that is a common disease to various plant species. Importantly, this resistance was not associated with any negative effects on growth or resistance against other environmental stresses.
Prof Ton said: “It is likely that plants have multiple epigenetic mechanisms to control their immune systems, but what is important about our research is that we have identified key loci of DNA methylation at the centre of the plant’s chromosomes, which control heritable disease resistance by influencing the responsiveness of defence genes across the plant’s genome.
“The study highlights how plants use a potentially reversible biochemical modification to DNA to pass on resistance to their offspring, in order to make them better capable of fighting off disease. We now hope to use this study to carry out further research to understand how these epigenetic loci control so many different defence genes. We are also keen to participate in more translational studies, in order to find out whether epigenetics can be used to prime disease resistance in crops that are vital to food supplies around the world.
“Scientists have debated for years whether and how plants are capable of passing on defence traits to their offspring via epigenetic mechanisms – we hope that our study helps to add clarity to the field of epigenetics, which in many ways can be regarded as ‘the dark matter of biology’. We also hope that our study motivates translational research to determine how far epigenetics can be exploited in the global fight against plant diseases.”
The P3 Plant Production and Protection Centre at the University of Sheffield is a centre of excellence for plant and soil biology that aims to translate its basic research into sustainable solutions for crop production and protection, often via partnership with agricultural industry.