title: Time-Resolved Investigation of Molecular Components Involved in the Induction of [Formula: see text] High Affinity Transport System in Maize Roots.
abstract: The induction, i.e., the rapid increase of nitrate ([Formula: see text]) uptake following the exposure of roots to the anion, was studied integrating physiological and molecular levels in maize roots. Responses to [Formula: see text] treatment were characterized in terms of changes in [Formula: see text] uptake rate and plasma membrane (PM) H+-ATPase activity and related to transcriptional and protein profiles ofNRT2, NRT3, andPM H+-ATPasegene families. The behavior of transcripts and proteins ofZmNRT2sandZmNRT3ssuggested that the regulation of the activity of inducible high-affinity transport system (iHATS) is mainly based on the transcriptional/translational modulation of the accessory protein ZmNRT3.1A. Furthermore, ZmNRT2.1 and ZmNRT3.1A appear to be associated in a ∼150 kDa oligomer. The expression trend during the induction of the 11 identifiedPM H+-ATPasetranscripts indicates that those mainly involved in the response to [Formula: see text] treatment areZmHA2andZmHA4. Yet, partial correlation between the gene expression, protein levels and enzyme activity suggests an involvement of post-transcriptional and post-translational mechanisms of regulation. A non-denaturing Deriphat-PAGE approach allowed demonstrating for the first time that PM H+-ATPase can occurin vivoas hexameric complex together with the already described monomeric and dimeric forms.
authors.affiliation: Faculty of Science and Technology, Free University of BolzanoBolzano, Italy.
authors.forename: Youry
authors.initials: Y
authors.lastname: Pii
authors.affiliation: Department of Biotechnology, University of VeronaVerona, Italy.
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Alessandrini
authors.affiliation: Department of Biotechnology, University of VeronaVerona, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Dall'Osto
authors.affiliation: Department of Biotechnology, University of VeronaVerona, Italy.
authors.forename: Katia
authors.initials: K
authors.lastname: Guardini
authors.affiliation: Department of Agricultural and Environmental Sciences - Production, Landscape, Agroenergy, University of MilanoMilano, Italy.
authors.forename: Bhakti
authors.initials: B
authors.lastname: Prinsi
authors.affiliation: Department of Agricultural and Environmental Sciences - Production, Landscape, Agroenergy, University of MilanoMilano, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Espen
authors.affiliation: Department of Biotechnology, University of VeronaVerona, Italy.
authors.forename: Anita
authors.initials: A
authors.lastname: Zamboni
authors.affiliation: Department of Biotechnology, University of VeronaVerona, Italy.
authors.forename: Zeno
authors.initials: Z
authors.lastname: Varanini
keywords: NO-3 induction; PM H+-ATPase; ZmNRT2.1; ZmNRT3.1A; maize; protein complexes