These authors contributed equally to this work.
Nitrogen deprivation promotes Populus root growth through global transcriptome reprogramming and activation of hierarchical genetic networks
Article first published online: 25 JUN 2013
© 2013 The Authors. New Phytologist © 2013 New Phytologist Trust
Special Issue: Featured papers on ‘Drought-induced forest mortality’
Volume 200, Issue 2, pages 483–497, October 2013
How to Cite
Wei, H., Yordanov, Y. S., Georgieva, T., Li, X. and Busov, V. (2013), Nitrogen deprivation promotes Populus root growth through global transcriptome reprogramming and activation of hierarchical genetic networks. New Phytologist, 200: 483–497. doi: 10.1111/nph.12375
- Issue published online: 18 SEP 2013
- Article first published online: 25 JUN 2013
- Manuscript Accepted: 20 MAY 2013
- Manuscript Received: 12 FEB 2013
- US Department of Energy (DOE)
- Poplar Genome Based Research for Carbon Sequestration in Terrestrial Ecosystems. Grant Numbers: DE-FG02-06ER64185, and DE-FG02-05ER64113
- the Consortium for Plant Biotechnology Research, Inc.. Grant Number: GO12026-203A
- the United States Department of Agriculture (USDA) CSREES
- USDA-NRI Plant Genome program. Grant Number: 2003-04345
- USDA CSREES, the Biotechnology Risk Assessment Research Grants Program. Grant Numbers: 2004-35300-14687, 2009-65504-05767, and ER65454-1040591-0018445
- abiotic stress;
- hierarchical genetic networks;
- nitrogen deprivation;
- Populus ;
- root architecture;
- root development
- We show a distinct and previously poorly characterized response of poplar (Populus tremula × Populus alba) roots to low nitrogen (LN), which involves activation of root growth and significant transcriptome reprogramming.
- Analysis of the temporal patterns of enriched ontologies among the differentially expressed genes revealed an ordered assembly of functionally cohesive biological events that aligned well with growth and morphological responses. A core set of 28 biological processes was significantly enriched across the whole studied period and 21 of these were also enriched in the roots of Arabidopsis thaliana during the LN response. More than half (15) of the 28 processes belong to gene ontology (GO) terms associated with signaling and signal transduction pathways, suggesting the presence of conserved signaling mechanisms triggered by LN.
- A reconstruction of genetic regulatory network analysis revealed a sub-network centered on a PtaNAC1 (P. tremula × alba NAM, ATAF, CUC 1) transcription factor. PtaNAC1 root-specific up-regulation increased root biomass and significantly changed the expression of the connected hub genes specifically under LN.
- Our results provide evidence that the root response to LN involves hierarchically structured genetic networks centered on key regulatory factors. Targeting these factors via genetic engineering or breeding approaches can allow dynamic adjustment of root architecture in response to variable nitrogen availabilities in the soil.