Integrative analysis in Pinus revealed long‐term heat stress splicing memory

Current scenario of climate change has led to increase number of studies describing main drivers in abiotic stress. Recent findings suggest that alternative splicing (AS) has a critical role in controlling plant response to high temperature. AS is a mechanism that allows organisms to create an assortment of RNA transcripts and proteins using single gene information. However, the most important insights suggested about stress AS could not be rigorously addressed because research has been focused on model species which only covered a narrow phylogenetic and life-cycle spectrum. Thus, AS degree of diversification among more dissimilar taxa in heat response is still largely unknown. To fill this gap, the present study employs a systems biology approach to examine how AS landscape responds and 'remembers' from heat stress in conifers, a group which have received little attention even though their position can solve key evolutionary questions. Contrary to angiosperms, we found that potential intron retention may not be the most prevalent type of AS. Furthermore, our integrative analysis with metabolome and proteome data places splicing as the main source of variation during the response. Finally, we evaluated possible acquired long-term splicing-memory in a diverse subset of events and, although this mechanism seems to be conserved in seed plants, AS dynamics are divergent. These discoveries reveal the particular way of remembering past temperature changes in long-lived plants and open the door to include species with unique features to determine the extent of conservation in gene expression regulation.