Asparagine is a major storage and transport form of nitrogen in plants. This amide amino acid can sustain Arabidopsis growth as a single nitrogen source. However, at the seedling stage, it inhibits root elongation and root hair formation in a dose-dependent manner, relative to control conditions without nitrogen. These responses are related to the amount of internal asparagine, as demonstrated in studies performed with asparaginase deficient mutants. Here we investigate transcriptional responses to asparagine in roots of ten day old Arabidopsis seedlings that were transferred to media with or without 20 mM asparagine for two hours.