Identified the key role of the phytohormone ABA in the response to Nitrogen availability in the root endodermis


Nitrate is an essential nutrient for plants and at the same time a very powerful signaling molecule that modulates multiple aspects of plant growth and development, including root development. However, the mechanisms and genes involved nitrate responses in different root cell types remain poorly understood.

To understand how the nitrate response is orchestrated across root cell types, in this work it was performed a spatiotemporal transcriptome analysis in different cell types of the root: the epidermis, cortex, endodermis, pericycle, and stele at different time points after nitrate treatment.GFP-based reporter lines were used for fluorescence-activated cell sorting (FACS) isolation of specific cell type.n this work, tt was found that nitrate-responsive genes and known biological processes are coordinately regulated in time, initiating in the outermost tissue layers and then propagated into innermost tissue layers. Integration of transcriptomic and available Transcription Factor-DNA interaction data into a gene regulatory network model, highlighted the endodermis as a central regulatory hub of nitrate responses and identified the Abscisic Acid (ABA)-related transcription factors ABF2 and ABF3 as key regulators of endodermal responses to nitrate.

This work offers an unprecedented spatiotemporal resolution of the root response to nitrate and identifies important new components of cell-specific gene regulatory networks controlling root responses to this nutrient signal.


Original Paper:

Contreras-López, O., Vidal, E.A., Riveras, E., Alvarez, J.M., Moyano, T.C., Sparks, E.E., Medina, J., Pasquino, A., Benfey, P.N., Coruzzi, G.M., Gutiérrez, R.A. 2022. Spatiotemporal analysis identifies ABF2 and ABF3 as key hubs of endodermal response to nitrate. Proceedings of the National Academy of Sciences 119. DOI: 10.1073/pnas.2107879119