GEOapplication/xmlftp://ftp.ncbi.nlm.nih.gov/geo/series/GSE114nnn/GSE114162/primaryOK2000000GenomicsArabidopsis thalianaExpression profiling by arrayhttps://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE114162GEOGSE0falseShoot responses to different nitrate supply to roots in wild-type and genotypes affected for cytokinin biosynthesis and transportPlants face temporal and spatial variation in nitrogen (N) availability. This includes heterogeneity in soil nitrate (NO3-) content. To face these constraints, plants modify their gene expression and physiological processes to optimize N acquisition. This plasticity relies on a complex long-distance root-shoot-root signaling network that remains poorly understood. We previously showed that cytokinin (CK) biosynthesis is required to trigger systemic N signaling. Here, we performed split-root experiments and used a combination of CK-related mutant analyses, hormone profiling, transcriptomic analysis, NO3- uptake assays, and root growth measurements to gain insight into systemic N signaling in Arabidopsis thaliana. By comparing wild-type plants and mutants affected in CK biosynthesis and ABCG14-dependent root-to-shoot translocation of CK, we revealed an important role for active trans-Zeatin (tZ) in systemic N signaling. Both rapid sentinel gene regulation and long-term functional acclimation to heterogeneous NO3- supply, including NO3- transport and root growth regulation, are likely mediated by the integration of tZ content in shoots. Furthermore, shoot transcriptome profiling revealed that glutamate/glutamine metabolism is likely a target of tZ root-to-shoot translocation, prompting an interesting hypothesis regarding shoot-to-root communication. Finally, this study highlights tZ-independent pathways regulating gene expression in shoots as well as NO3- uptake activity in response to total N-deprivation. We used microarrays to detail transcriptional reprogramming occurring in shoots in response to heterogeneous nitrate supply compared to homogeneous nitrate supply in wild-type Arabidopsis thaliana plants and in two mutants affected in cytokinin biosynthesis and transport.2018/05/09GSE114162GSM3136693GSM3136694GSM3136707GSM3136708GSM3136709GSM3136703GSM3136714GSM3136715GSM3136704GSM3136716GSM3136705GSM3136706GSM3136710GSM3136699GSM3136700GSM3136711GSM3136712GSM3136701GSM3136713GSM3136702GSM3136695GSM3136696GSM3136697GSM313669817133114162Arabidopsis thaliana