Functional Characterization of the Arabidopsis Abscisic Acid Transporters NPF4.5 and NPF4.6 in Xenopus Oocytes
Résumé
Dynamic reprogramming of gene regulatory networks (GRNs) enables organisms to rapidly
respond to environmental perturbation. However, the underlying transient interactions
between transcription factors (TFs) and genome-wide targets typically elude biochemical
detection. Here, we capture both stable and transient TF-target interactions genome-wide
within minutes after controlled TF nuclear import using time-series chromatin immunoprecipitation
(ChIP-seq) and/or DNA adenine methyltransferase identification (DamID-seq).
The transient TF-target interactions captured uncover the early mode-of-action of NIN-LIKE
PROTEIN 7 (NLP7), a master regulator of the nitrogen signaling pathway in plants. These
transient NLP7 targets captured in root cells using temporal TF perturbation account for 50%
of NLP7-regulated genes not detectably bound by NLP7 in planta. Rapid and transient NLP7
binding activates early nitrogen response TFs, which we validate to amplify the NLP7-initiated
transcriptional cascade. Our approaches to capture transient TF-target interactions genomewide
can be applied to validate dynamic GRN models for any pathway or organism of interest.
Origine : Publication financée par une institution
