Coding-Sequence Identification and Transcriptional Profiling of Nine and Four From Tobacco Revealed Their Differential Regulation by Developmental Stages, Nitrogen Nutrition, and Photoperiod.

Although many members encoding different ammonium- and nitrate-transporters (AMTs, NRTs) were identified and functionally characterized from several plant species, little is known about molecular components for [Formula: see text]- and [Formula: see text] acquisition/transport in tobacco, which is often used as a plant model for biological studies besides its agricultural and industrial interest. We reported here the first molecular identification in tobacco () of nine and four , which are respectively divided into four () and two () clusters and whose functionalities were preliminarily evidenced by heterologous functional-complementation in yeast or Arabidopsis. Tissue-specific transcriptional profiling by qPCR revealed that / mRNA occurred widely in leaves, flower organs and roots; only were strongly transcribed in the aged leaves, implying their dominant roles in N-remobilization from source/senescent tissues.

Molecular identification of tobacco NtAMT1.3 that mediated ammonium root-influx with high affinity and improved plant growth on ammonium when overexpressed in Arabidopsis and tobacco.

Although biological functions of ammonium (NH) transporters (AMTs) have been intensively studied in many plant species, little is known about molecular bases responsible for NH movement in tobacco. Here, we reported the identification and functional characterization of a putative NH transporter NtAMT1.3 from tobacco (Nicotiana tabacum).

Rice DUR3 mediates high-affinity urea transport and plays an effective role in improvement of urea acquisition and utilization when expressed in Arabidopsis.

• Despite the great agricultural and ecological importance of efficient use of urea-containing nitrogen fertilizers by crops, molecular and physiological identities of urea transport in higher plants have been investigated only in Arabidopsis. • We performed short-time urea-influx assays which have identified a low-affinity and high-affinity (K(m) of 7.55 μM) transport system for urea-uptake by rice roots (Oryza sativa).