title: Nitrate signaling and early responses in Arabidopsis roots.
abstract: Nitrogen (N) is an essential macronutrient that impacts many aspects of plant physiology, growth, and development. Besides its nutritional role, N nutrient and metabolites act as signaling molecules that regulate the expression of a wide range of genes and biological processes. In this review, we describe recent advances in the understanding of components of the nitrate signaling pathway. Recent evidence posits that in one nitrate signaling pathway, nitrate sensed by NRT1.1 activates a phospholipase C activity that is necessary for increased cytosolic calcium levels. The nitrate-elicited calcium increase presumably activates calcium sensors, kinases, or phosphatases, resulting in changes in expression of primary nitrate response genes. Consistent with this model, nitrate treatments elicit proteome-wide changes in phosphorylation patterns in a wide range of proteins, including transporters, metabolic enzymes, kinases, phosphatases, and other regulatory proteins. Identifying and characterizing the function of the different players involved in this and other nitrate signaling pathways and their functional relationships is the next step to understand N responses in plants.
authors.affiliation: FONDAP Center for Genome Regulation. Millennium Nucleus Center for Plant Systems and Synthetic Biology. Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Avenida Libertador Bernardo O'Higgins 340, Santiago, Chile 8331150.
authors.forename: Soledad F
authors.initials: SF
authors.lastname: Undurraga
authors.affiliation: FONDAP Center for Genome Regulation. Millennium Nucleus Center for Plant Systems and Synthetic Biology. Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Avenida Libertador Bernardo O'Higgins 340, Santiago, Chile 8331150.
authors.forename: Catalina
authors.initials: C
authors.lastname: Ibarra-Henríquez
authors.affiliation: FONDAP Center for Genome Regulation. Millennium Nucleus Center for Plant Systems and Synthetic Biology. Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Avenida Libertador Bernardo O'Higgins 340, Santiago, Chile 8331150.
authors.forename: Isabel
authors.initials: I
authors.lastname: Fredes
authors.affiliation: FONDAP Center for Genome Regulation. Millennium Nucleus Center for Plant Systems and Synthetic Biology. Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Avenida Libertador Bernardo O'Higgins 340, Santiago, Chile 8331150.
authors.forename: José Miguel
authors.initials: JM
authors.lastname: Álvarez
authors.affiliation: FONDAP Center for Genome Regulation. Millennium Nucleus Center for Plant Systems and Synthetic Biology. Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Avenida Libertador Bernardo O'Higgins 340, Santiago, Chile 8331150.
authors.forename: Rodrigo A
authors.initials: RA
authors.lastname: Gutiérrez
mesh_terms: D017360:Arabidopsis / Q000502:physiology*; D002118:Calcium / Q000378:metabolism*; D009566:Nitrates / Q000502:physiology*; D010766:Phosphorylation; D010940:Plant Proteins / Q000378:metabolism*; D018517:Plant Roots / Q000502:physiology; D015398:Signal Transduction
chemical_list: D009566:Nitrates; D010940:Plant Proteins; D002118:Calcium
keywords: Gene expression; nitrate; nitrogen; phospholipase C; phosphorylation; primary response; signaling.