Non-Coding and Epigenetic Regulators of Ambient Temperature Sensitive Flowering

Summary

Ambient temperature is a signal which promotes flowering in many plant species. This ambient temperature sensitive flowering is regulated by many genes and proteins, but also by RNA transcripts that do not code for proteins and direct modifications to the DNA or the chromatin.

In my thesis, I delved into these non-coding and epigenetic regulators in the model plant Arabidopsis thaliana. Our results indicate that direct modification of the DNA by adding methylation groups, called DNA methylation, is normally stable after a change in temperature. However, when plants are mutated for the DNA methylation maintenance gene DDM1, this stability is lost and plants are hypersensitive to changes in temperature. Additionally, we found that a specific modification to the chromatin, called H3K36me3, is required to integrate both signals from temperature and daylength. Together, this thesis found some novel regulators and deepened our knowledge of the epigenetic regulation of plants sensing the environment.