When the cell needs to respond to the environment: A chromatin-splicing love affair

Alternative splicing enables cells to acquire novel phenotypic traits for adaptation to changes in the environment. However, the mechanisms that allow these dynamic changes to occur in a timely and sustained manner remain unknown. Recent investigations unveiled a new regulatory layer important for splicing dynamics and memory: the chromatin. A growing body of evidence suggests that histone modifications, DNA methylation, nucleosome positioning, and three-dimensional chromatin organization play significant roles in determining specific splicing outcomes in response to different stimuli. In this review, we highlight the evidence supporting a chromatin-mediated regulation of alternative splicing in response to environmental cues across a diverse range of organisms. This regulation encompasses local changes in chromatin modifications, as well as alterations in higher-order nuclear organization. Such modifications shape the genome to facilitate highly dynamic and coordinated splicing responses to external stimuli, potentially aiding in long-term adaptations to environmental changes, such as those induced by climate change.