Epigenetic processes in plant stress priming: Open questions and new approaches

Priming reflects the capacity of plants to memorise environmental stress experience and improve their response to recurring stress. Epigenetic modifications in DNA and associated histone proteins may carry short-term and long-term memory in the same plant or mediate transgenerational effects, but the evidence is still largely circumstantial. New experimental tools now enable scientists to perform targeted manipulations that either prevent or generate a particular epigenetic modification in a particular location of the genome. Such 'reverse epigenetics' approaches allow for the interrogation of causality between individual priming-induced modifications and their role for altering gene expression and plant performance under recurring stress. Furthermore, combining site-directed epigenetic manipulation with conditional and celltype specific promoters creates novel opportunities to test and engineer spatiotemporal patterns of priming.

Automated summary

Priming is a plant's ability to remember environmental stress and improve their response to recurring stress. Epigenetic modifications in DNA and histone proteins may carry short-term and long-term memory or mediate transgenerational effects in plants. New experimental tools allow scientists to manipulate epigenetic modifications in specific locations of the genome, enabling them to study the causality between these modifications and gene expression under stress. Combining site-directed epigenetic manipulation with specific promoters creates opportunities for studying and engineering spatiotemporal patterns of priming.