Chromatin remodeling factors regulate environmental stress responses in plants

Environmental stress from climate change and agricultural activity threatens global plant biodiversity as well as crop yield and quality. As sessile organisms, plants must maintain the integrity of their genomes and adjust gene expression to adapt to various environmental changes. In eukaryotes, nucleosomes are the basic unit of chromatin around which genomic DNA is packaged by condensation. To enable dynamic access to packaged DNA, eukaryotes have evolved Snf2 (sucrose nonfermenting 2) family proteins as chromatin remodeling factors (CHRs) that modulate the position of nucleosomes on chromatin. During plant stress responses, CHRs are recruited to specific genomic loci, where they regulate the distribution or composition of nucleosomes, which in turn alters the accessibility of these loci to general transcription or DNA damage repair machinery. Moreover, CHRs interplay with other epigenetic mechanisms, including DNA methylation, histone modifications, and deposition of histone variants. CHRs are also involved in RNA processing at the post-transcriptional level. In this review, we discuss major advances in our understanding of the mechanisms by which CHRs function during plants' response to environmental stress.