Transposable elements (TE) are ubiquitous mobile DNA elements present in all eukaryote genomes. TEs are considered as endogenous molecular parasites based on their ability to hijack the cellular machinery in order to increase their DNA copy number and, therefore, their spread through the genome. TEs take a fundamental role in genome evolution contributing to genome expansion and as a source of genetic and epigenetic variation. Indeed, TEs can display regulatory roles providing new networks controlling gene expression. However, TE activity can be deleterious and pose a risk for genome integrity as well as a source of mutations, leading to loss of fitness and disease. Thus, hosts have developed strategies to subdue TE mobility and transposition which imply epigenetic and antiviral pathways. Nonetheless, little is known about the role of these regulatory mechanisms in the natural variation for TE content, that we observed in previous works, in Arabidopsis natural accessions and its potential effect in plant local adaptation.
In this work, I am focus on how transposon activity is recognized and regulated in different accessions of Arabidopsis thaliana. Monitoring transcription of a large set of ecotypes in multiple conditions and generating mutant lines depleted for TE silencing, will allow the identification of correlations between functional TEs (mobilome) and silencing pathways activity. Hence, I could connect active TEs population and TE content in natural accession of Arabidopsis and its potential role in plant local adaptation.