RRC ID 71520
Author Misawa F, Ito M, Nosaki S, Nishida H, Watanabe M, Suzuki T, Miura K, Kawaguchi M, Suzaki T.
Title Nitrate transport via NRT2.1 mediates NIN-LIKE PROTEIN-dependent suppression of root nodulation in Lotus japonicus.
Journal Plant Cell
Abstract Legumes have adaptive mechanisms that regulate nodulation in response to the amount of nitrogen in the soil. In Lotus japonicus, two NODULE INCEPTION (NIN)-LIKE PROTEIN (NLP) transcription factors, LjNLP4 and LjNLP1, play pivotal roles in the negative regulation of nodulation by controlling the expression of symbiotic genes in high nitrate conditions. Despite an improved understanding of the molecular basis for regulating nodulation, how nitrate plays a role in the signaling pathway to negatively regulate this process is largely unknown. Here, we show that nitrate transport via NITRATE TRANSPORTER 2.1 (LjNRT2.1) is a key step in the NLP signaling pathway to control nodulation. A mutation in the LjNRT2.1 gene attenuates the nitrate-induced control of nodulation. LjNLP1 is necessary and sufficient to induce LjNRT2.1 expression, thereby regulating nitrate uptake/transport. Our data suggest that LjNRT2.1-mediated nitrate uptake/transport is required for LjNLP4 nuclear localization and induction/repression of symbiotic genes. We further show that LjNIN, a positive regulator of nodulation, counteracts the LjNLP1-dependent induction of LjNRT2.1 expression, which is linked to a reduction in nitrate uptake. These findings suggest a plant strategy in which nitrogen acquisition switches from obtaining nitrogen from the soil to symbiotic nitrogen fixation.
Volume 34(5)
Pages 1844-1862
Published 2022-2-11
DOI 10.1093/plcell/koac046
PII 6526407
PMID 35146519
PMC PMC9048892
MeSH Gene Expression Regulation, Plant Lotus* / genetics Lotus* / metabolism Nitrates / metabolism Nitrogen / metabolism Plant Proteins / metabolism Plant Root Nodulation / genetics Root Nodules, Plant / genetics Root Nodules, Plant / metabolism Soil Symbiosis / physiology
IF 9.618
Lotus / Glycine Miyakojima MG-20