Nitrate Reductase mRNA Regulation in Nicotiana plumbaginifolia Nitrate Reductase-Deficient Mutants

Pouteau, S..; Cherel, I..; Vaucheret, H..; Caboche, M..

Plant Cell 1(11): 1111-1120


ISSN/ISBN: 1532-298X
PMID: 12359888
DOI: 10.1105/tpc.1.11.1111
Accession: 001894870

Download citation:  

Article/Abstract emailed within 0-6 h
Payments are secure & encrypted
Powered by Stripe
Powered by PayPal

Light and substrate regulation of nitrate reductase (NR) expression were compared in wild type and mutant lines of Nicotiana plumbaginifolia. Mutants affected in the NR structural gene (nia) or in the biosynthesis of the NR molybdenum cofactor (cnx) were examined. nia mutants expressing a defective apoenzyme, as well as cnx mutants, overexpressed NR mRNA, whereas nia mutants devoid of detectable NR protein had reduced or undetectable NR mRNA levels. Diurnal fluctuations of NR mRNA were specifically abolished in nia and cnx mutants, suggesting that the integrity of NR catalytic activity is required for the expression of diurnal oscillations. Unlike some fungal mutants, the nia and cnx mutants examined retained nitrate inducibility of NR expression. The possibility of autogenous control of NR expression in higher plants is discussed.