Three NPF genes in Arabidopsis are necessary for normal nitrogen cycling under low nitrogen stress.
Plant Physiol Biochem
; 143: 1-10, 2019 Oct.
Article
in En
| MEDLINE
| ID: mdl-31473400
ABSTRACT
Internal nitrogen (N) cycling is crucial to N use efficiency. For example, N may be remobilized from older, shaded leaves to young leaves near the apex that receive more direct sunlight, where the N can be used more effectively for photosynthesis. Yet our understanding of the mechanisms and regulation of N transport is limited. To identify relevant transporters in Arabidopsis, fifteen transporter knockout mutants were screened for defects in leaf N export using nitrogen-13 (13N) administered as 13NH3 gas to leaves. We found that three nitrate/peptide transporter family (NPF) genes were necessary for normal leaf N export under low N but not adequate soil N availability, including AtNPF7.1, which has not been previously characterized. High-throughput phenotyping revealed altered leaf area and chlorophyll fluorescence relative to wild-type plants. High AtNPF7.1 expression in flowers and large flower stalks of Atnpf7.1 mutants in low N suggests that AtNPF7.1 influences leaf N export via sink-to-source feedback, perhaps via a role in sensing plant internal N-status. We also identified previously unreported phenotypes for the mutants of the other two NPF transporters that indicate possible roles in N sensing networks.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Arabidopsis
/
Arabidopsis Proteins
/
Nitrogen
Language:
En
Journal:
Plant Physiol Biochem
Journal subject:
BIOQUIMICA
/
BOTANICA
Year:
2019
Document type:
Article