title: Qualitative network models and genome-wide expression data define carbon/nitrogen-responsive molecular machines in Arabidopsis.
abstract: BACKGROUND
  Carbon (C) and nitrogen (N) metabolites can regulate gene expression in Arabidopsis thaliana. Here, we use multi-network analysis of microarray data to identify molecular networks regulated by C and N in the Arabidopsis root system.
  
  
  RESULTS
  We used the Arabidopsis whole genome Affymetrix gene chip to explore global gene expression responses in plants exposed transiently to a matrix of C and N treatments. We used ANOVA analysis to define quantitative models of regulation for all detected genes. Our results suggest that about half of the Arabidopsis transcriptome is regulated by C, N or CN interactions. We found ample evidence for interactions between C and N that include genes involved in metabolic pathways, protein degradation and auxin signaling. To provide a global, yet detailed, view of how the cell molecular network is adjusted in response to the CN treatments, we constructed a qualitative multi-network model of the Arabidopsis metabolic and regulatory molecular network, including 6,176 genes, 1,459 metabolites and 230,900 interactions among them. We integrated the quantitative models of CN gene regulation with the wiring diagram in the multi-network, and identified specific interacting genes in biological modules that respond to C, N or CN treatments.
  
  
  CONCLUSIONS
  Our results indicate that CN regulation occurs at multiple levels, including potential post-transcriptional control by microRNAs. The network analysis of our systematic dataset of CN treatments indicates that CN sensing is a mechanism that coordinates the global and coordinated regulation of specific sets of molecular machines in the plant cell.
authors.affiliation: Department of Biology, New York University, Washington Square East, New York, NY 10003, USA. rodrigo@nyu.edu
authors.forename: Rodrigo A
authors.initials: RA
authors.lastname: Gutiérrez
authors.forename: Laurence V
authors.initials: LV
authors.lastname: Lejay
authors.forename: Alexis
authors.initials: A
authors.lastname: Dean
authors.forename: Francesca
authors.initials: F
authors.lastname: Chiaromonte
authors.forename: Dennis E
authors.initials: DE
authors.lastname: Shasha
authors.forename: Gloria M
authors.initials: GM
authors.lastname: Coruzzi
mesh_terms: D017360:Arabidopsis / Q000235:genetics*; D002244:Carbon / Q000378:metabolism*; D016000:Cluster Analysis; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D053263:Gene Regulatory Networks; D017343:Genes, Plant; D018745:Genome, Plant / Q000235:genetics*; D007210:Indoleacetic Acids / Q000378:metabolism; D008957:Models, Genetic; D009584:Nitrogen / Q000378:metabolism*; D018517:Plant Roots / Q000235:genetics; D013997:Time Factors
chemical_list: D007210:Indoleacetic Acids; D002244:Carbon; D009584:Nitrogen