Alternative splicing in plants: emerging order from chaos

Alternative splicing (AS) is a key evolutionary innovation that adds a regulatory layer to gene expression. Being predominantly co-transcriptional, AS is influenced by chromatin state, enabling appropriate and repeatable gene expression patterns under stress or adaptive conditions. Chromatin state may influence early co-transcriptional steps of AS, potentially modulating gene expression patterns during environmental or adaptive responses. Recent evidence shows that AS not only modulates gene expression but can also increase protein diversity under specific conditions. To fully understand its roles in regulation, diversification, and evolution, research must move beyond condition-specific studies to population-level analyses. Comparing relict (survivors from glacial refugia) and global arabidopsis (Arabidopsis thaliana) populations for transcript isoform and protein diversity could reveal how AS contributes to stress tolerance and adaptation.