Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.08.07.240580v1?rss=1 Authors: Parvathaneni, R. K., Kumar, I., Braud, M., Eveland, A. L. Abstract: The effects of drought stress can be devastating to crop production worldwide. A grand challenge facing agriculture is the development of crop varieties with improved drought resilience through breeding or biotechnology. To accelerate this, a mechanistic understanding is needed of the regulatory networks underlying drought response pathways in crop genomes and the genetic elements that modulate them. In this study, we explore the regulatory landscape of sorghum [Sorghum bicolor (L.) Moench] in response to controlled-environment drought stress. Sorghum is a C4 cereal crop with innate drought resilience and is an untapped resource of allelic diversity. To define molecular signatures of drought response, we mapped genome-wide chromatin accessibility using an Assay for Transposase Accessible Chromatin by sequencing (ATAC-seq) and analyzed parallel transcriptional profiles in drought-stressed sorghum shoot and root tissues compared to well-watered controls. Drought-responsive changes in chromatin accessibility were largely found in proximal promoters of differentially expressed genes and also in distal regions of the genome. These data were integrated to infer gene network connections and cis-regulatory modules that underlie drought response in sorghum, including cross-talk among hormone and nutrient pathways and the transcription factors that control them. Our analyses provide drought-inducible regulatory modules in the sorghum genome that can be leveraged for fine-tuning responses to stress, mining diversity for advantageous alleles, and translating across species to ultimately improve productivity and sustainability in sorghum and closely related cereal crops. Copy rights belong to original authors. Visit the link for more info