Research Focus

Priming and Memory Mechanisms in Plants for Overcoming Stress

Plants cannot move to escape adverse environmental conditions, so they have developed specialized adaptive abilities for survival and reproduction. However, our understanding of these abilities remains limited.

Research shows that plants can retain memories, which influence their growth, development, and stress responses. Plant memories are obtained through a process called priming. Priming in plants is similar to learning in animals, as both involve behavioral changes based on experience. In our laboratory, using Arabidopsis thaliana as a reference plant, we discovered that the genes HSFA2 and HSA32 help maintain memory generated by high-temperature priming, a process we refer to as heat acclimation memory.

HSFA2 is a heat-inducible transcription factor that regulates two classes of memory genes. It binds to the promoters of these genes, causing histone modifications (H3K4me3) at these sites, a form of epigenetic regulation.

HSA32 is a unique, heat-inducible protein with an enzyme-like structure found in all terrestrial plants. HSA32 stabilizes another heat-inducible protein, HSP101, which is directly related to heat tolerance. In turn, HSP101 slows the degradation of HSA32, creating a positive feedback loop that sustains acquired thermotolerance. We are currently investigating the molecular mechanisms underlying this feedback loop and its evolutionary origins.

Yee-yung Charng