PRJNA518019
Exaiptasia pallida Raw sequence reads
Eukaryotic DNA is wound around histone proteins in a complex called nucleosome. This complex is regulated vastly as histones are removed to expose regulatory sites, such as cis-regulatory elements (CREs) and promoters to allow binding of transcription factors (TFs) and other regulatory proteins. Identification of enriched motifs within these active CREs can, therefore, reveal genes associated with a transcriptional regulatory network. We have implemented Assay for Transposase-Accessible Chromatin with high-throughput sequencing (ATAC-seq) and RNA-seq to study the cnidarian-dinoflagellate model Exaptasia pallida to expose the role of chromatin dynamics in response to thermal stress, and how it affected by the animal symbiotic state. We have identified 1309 sites (853 in apo-symbiotic morph, 787 in symbiotic morph and 331 overlapping sites) that change their accessibility in response to thermal changes. Integrating chromatin accessibility profiles with transcription profiles revealed how symbiotic state has a profound effect on stress response directions of the animal and potential TFs that direct them. This work opens a new path towards understanding thermal stress gene regulation with the association of gene activity and chromatin accessibility. Therefore, our results show that chromatin structure may play an important role in regulating stress response gene expression in cnidarian-dinoflagellate symbioses under global warming.