A Mesoscale Abscisic Acid Hormone Interactome Reveals a Dynamic Signaling Landscape in Arabidopsis

The sesquiterpenoid abscisic acid (ABA) mediates an assortment of responses across a variety of kingdoms including both higher plants and animals. In plants, where most is known, a linear core ABA signaling pathway has been identified. However, the complexity of ABA-dependent gene expression suggests that ABA functions through an intricate network. Here, using systems biology approaches that focused on genes transcriptionally regulated by ABA, we defined an ABA signaling network of over 500 interactions among 138 proteins. This map greatly expanded ABA core signaling but was still manageable for systematic analysis. For example, functional analysis was used to identify an ABA module centered on two sucrose nonfermenting (SNF)-like kinases. We also used coexpression analysis of interacting partners within the network to uncover dynamic subnetwork structures in response to different abiotic stresses. This comprehensive ABA resource allows for application of approaches to understanding ABA functions in higher plants. [Display omitted] •High-quality ABA network encompassing 500 interactions among 138 proteins•Doubled the number of proteins that interact with core ABA signaling components•Identified an SNRK3 signaling module that attenuates early ABA responses•Mapping coexpression predicted the function of genes under abiotic stresses Lumba et al. define a focused ABA signaling network of over 500 interactions among 138 proteins. The network can be queried functionally to define genes involved in ABA signaling. When merged with global expression patterns centered on abiotic stresses, the ABA network reveals specific modules related to each stress condition.