Investigating plant metabolic regulation under drought stress through the integration of public datasets

The environmental changes of the last decades have been bringing several problems to plants worldwide, forcing them to face various stresses. Of these, one of the most critical is represented by water deficiency, which can affect plant growth, especially in hot regions. Therefore, it is crucial to better understand gene regulations and pathways used by plants to withstand these conditions. In this perspective, we leveraged RNA-seq data published on public databases, deriving from plants grown in control and drought stress conditions. We focused our interest on three species, i.e. two dicots (Arabidopsis thaliana and Solanum lycopersicum) and one monocot (Triticum aestivum). This data were mainly represented by leaves, but included also other organs, and were filtered in such a way to maintain only what is associated to published studies. A Principal Component Analysis was performed for each species on the whole data, not uncovering a clear separation based on treatment, but mainly on BioProject and organ. However, the employment of batch-effect removal strategies reduced this trend, letting the relative importance of treatment increase. Differential expression analysis was then performed, followed by enrichment analysis on the results from the previous step, focusing in particular on the "response to water deprivation" process, which was found highly enriched in A. thaliana and T. aestivum. Finally, an orthology analysis was conducted, from which some differentially expressed orthogroups shared between the three species emerged, particularly among T. aestivum and A. thaliana.