Transcription profiling by array of Arabidopsis transcription factor ABI3 in root protoplasts

Deciphering gene regulatory networks (GRNs) is a key for understanding gene expression regulations in living systems. Here, we describe the investigation of the ABSCISIC ACID INSENSITIVE 3 (ABI3) plant transcription factor GRN vicinity by a technique called Network Walking. The method involves transient transformation of protoplasts and inducible nuclear re-localization of transcription factors along with transcriptomic analysis. This genome-wide approach allowed the de novo recovery of i) direct and indirect ABI3 target genes, ii) cis-binding site preference, and iii) biological processes regulated by this canonical abscisic acid response factor. This work improves our knowledge of ABI3 action by inferring network motifs (such as Feed Forwar Loops) under its influence. The novel high-throughput-oriented technique will help accelerate GRN systems investigations in plants, as well as in other organisms. This work studies ABI3 direct and indirect targets by a technique named Network Walking. Root/protoplasts were treated with or without dexamethasone (DEX) and cycloheximide (CHX). 3 reps each.