Nitrate transporter 1.1 alleviates lead toxicity in Arabidopsis by preventing rhizosphere acidification.
J Exp Bot
; 70(21): 6363-6374, 2019 11 18.
Article
em En
| MEDLINE
| ID: mdl-31414122
ABSTRACT
Identification of the mechanisms that control lead (Pb) concentration in plants is a prerequisite for minimizing dietary uptake of Pb from contaminated crops. This study examines how nitrate uptake by roots affects Pb uptake and reveals a new resistance strategy for plants to cope with Pb contamination. We investigated the interaction between nitrate transporter (NRT)-mediated NO3- uptake and exposure to Pb in Arabidopsis using NRT-related mutants. Exposure to Pb specifically stimulated NRT1.1-mediated nitrate uptake. Loss of function of NRT1.1 in nrt1.1-knockout mutants resulted in greater Pb toxicity and higher Pb accumulation in nitrate-sufficient growth medium, whereas no difference was seen between wild-type plants and null-mutants for NRT1.2, NRT2.1, NRT2.2, NRT2.4, and NRT2.5. These results indicate that only NRT1.1-mediated NO3- uptake alleviated Pb toxicity in the plants. Further examination indicated that rhizosphere acidification, which favors Pb entry to roots by increasing its availability, is prevented when NRT1.1 is functional and both NO3- and NH4+ are present in the medium.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Plantas
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Ácidos
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Arabidopsis
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Proteínas de Transporte de Ânions
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Rizosfera
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Chumbo
Idioma:
En
Revista:
J Exp Bot
Ano de publicação:
2019
Tipo de documento:
Article