title: Shoot HAR1 mediates nitrate inhibition of nodulation in Lotus japonicus.
abstract: Nitrate is a major environmental factor in the inhibition of nodulation. In a model legume Lotus japonicus, a CLV1-like receptor kinase, HAR1, mediates nitrate inhibition and autoregulation of nodulation. Autoregulation of nodulation involves root-to-shoot-to-root long-distance communication, and HAR1 functions in shoots. However, it remains elusive where HAR1 functions in the nitrate inhibition of nodulation. We performed grafting experiments with the har1 mutant under various nitrate conditions, and found that shoot HAR1 is critical for the inhibition of nodulation at 10 mM nitrate. Combined with our recent finding that the nitrate-induced CLE-RS2 glycopeptide binds directly to the HAR1 receptor, this result suggests that CLE-RS2/HAR1 long-distance signaling plays an important role in the both nitrate inhibition and the autoregulation of nodulation.
authors.affiliation: a Division of Biological Science; Graduate School of Science; Nagoya University ; Nagoya , Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Okamoto
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Kawaguchi
mesh_terms: D006706:Homeostasis; D000070116:Lotus / Q000502:physiology*; D009566:Nitrates / Q000378:metabolism*; D010940:Plant Proteins / Q000378:metabolism*; D055170:Plant Root Nodulation; D018520:Plant Shoots / Q000378:metabolism
chemical_list: D009566:Nitrates; D010940:Plant Proteins
keywords: CLE, CLAVATA3/ESR-related; CLV1, CLAVATA1; HAR1; HAR1, HYPERNODULATION ABERRANT ROOT FORMATION1; LRR-RK, Leucine-rich repeat receptor kinase; NARK, NODULE AUTOREGULATION RECEPTOR KINASE; SUNN, SUPER NUMERIC NODULES; grafting; long-distance signaling; nitrate; nodule