Plants possess remarkable molecular mechanisms that allow them to adapt to environmental fluctuations, including episodes of heat stress. When exposed to mild, non-lethal heat conditions, plants can “memorize” this experience and respond more effectively to future, more severe stress. This adaptive process, known as thermomemory, is crucial for survival under changing climates and contributes to long-term plant resilience and productivity. Understanding how plants establish, maintain, and recall thermomemory is therefore essential for developing crops capable of withstanding the increasing frequency of heatwaves associated with global climate change.
In recent years, chemical modifications of RNA molecules, collectively referred to as epitranscriptomic marks, have emerged as important regulators of gene expression. Among these modifications, N6-methyladenosine (m⁶A) and 5-methylcytosine (m⁵C) are particularly abundant and dynamic. They are installed by writer enzymes (methyltransferases), removed by erasers (demethylases), and recognized by reader proteins that interpret these marks to control RNA fate and function. These mechanisms influence RNA stability, translation, and localization, thereby fine-tuning the cellular response to developmental and environmental cues. Despite their recognized importance, the contribution of m⁶A and m⁵C pathways to heat stress adaptation and thermomemory has remained largely unexplored.
The overall goal of this project was to uncover the role of the plant epitranscriptome in regulating gene expression during thermomemory, using Arabidopsis thaliana as a model system. Specifically, the research aimed to:
i) Evaluate how writer, reader, and eraser proteins involved in m⁶A and m⁵C modifications influence the establishment and recovery of thermomemory through phenotypic assays of heat stress tolerance;
ii) Characterize the spatiotemporal expression patterns of selected m⁶A reader proteins in the shoot apical meristem (SAM) — a crucial region for growth regulation and developmental plasticity under stress;
iii) Combine molecular and imaging approaches, including RNA in situ hybridization and confocal laser scanning microscopy, to localize reader transcripts and protein accumulation in SAM tissues across thermomemory time points;
iv) Investigate the interaction between epitranscriptomic regulation and meristem maintenance genes to determine how RNA methylation pathways contribute to the maintenance of meristem activity under heat stress.
By integrating genetics, cell biology, and advanced microscopy, this project provides novel insights into how RNA methylation acts as a regulatory layer connecting environmental perception to gene expression plasticity. Understanding these mechanisms in Arabidopsis serves as a foundation for translating epitranscriptomic principles into crop systems, ultimately contributing to the development of heat-resilient plants and supporting global efforts toward sustainable agriculture under climate stress.
