title: 3-hydroxy-3-methylglutaryl coenzyme a reductase 1 interacts with NORK and is crucial for nodulation in Medicago truncatula.
abstract: NORK in legumes encodes a receptor-like kinase that is required for Nod factor signaling and root nodule development. Using Medicago truncatula NORK as bait in a yeast two-hybrid assay, we identified 3-hydroxy-3-methylglutaryl CoA reductase 1 (Mt HMGR1) as a NORK interacting partner. HMGR1 belongs to a multigene family in M. truncatula, and different HMGR isoforms are key enzymes in the mevalonate biosynthetic pathway leading to the production of a diverse array of isoprenoid compounds. Testing other HMGR members revealed a specific interaction between NORK and HMGR1. Mutagenesis and deletion analysis showed that this interaction requires the cytosolic active kinase domain of NORK and the cytosolic catalytic domain of HMGR1. NORK homologs from Lotus japonicus and Sesbania rostrata also interacted with Mt HMGR1, but homologous nonsymbiotic kinases of M. truncatula did not. Pharmacological inhibition of HMGR activities decreased nodule number and delayed nodulation, supporting the importance of the mevalonate pathway in symbiotic development. Decreasing HMGR1 expression in M. truncatula transgenic roots by RNA interference led to a dramatic decrease in nodulation, confirming that HMGR1 is essential for nodule development. Recruitment of HMGR1 by NORK could be required for production of specific isoprenoid compounds, such as cytokinins, phytosteroids, or isoprenoid moieties involved in modification of signaling proteins.
authors.affiliation: Institut des Sciences du Végétal, Centre National de la Recherche Scientifique, Unité Propre de Recherche 2355, 91198 Gif-sur-Yvette Cedex, France.
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Kevei
authors.forename: Géraldine
authors.initials: G
authors.lastname: Lougnon
authors.forename: Peter
authors.initials: P
authors.lastname: Mergaert
authors.forename: Gábor V
authors.initials: GV
authors.lastname: Horváth
authors.forename: Attila
authors.initials: A
authors.lastname: Kereszt
authors.forename: Dhileepkumar
authors.initials: D
authors.lastname: Jayaraman
authors.forename: Najia
authors.initials: N
authors.lastname: Zaman
authors.forename: Fabian
authors.initials: F
authors.lastname: Marcel
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Regulski
authors.forename: György B
authors.initials: GB
authors.lastname: Kiss
authors.forename: Adam
authors.initials: A
authors.lastname: Kondorosi
authors.forename: Gabriella
authors.initials: G
authors.lastname: Endre
authors.forename: Eva
authors.initials: E
authors.lastname: Kondorosi
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Ané
mesh_terms: D000595:Amino Acid Sequence; D004789:Enzyme Activation / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D006903:Hydroxymethylglutaryl CoA Reductases / Q000235:genetics / Q000378:metabolism*; D047468:Immunoprecipitation; D017403:In Situ Hybridization; D008148:Lovastatin / Q000494:pharmacology; D046913:Medicago truncatula / Q000235:genetics / Q000378:metabolism* / Q000382:microbiology; D008957:Models, Genetic; D008969:Molecular Sequence Data; D009154:Mutation; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D020033:Protein Isoforms / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D017434:Protein Structure, Tertiary; D034622:RNA Interference; D020133:Reverse Transcriptase Polymerase Chain Reaction; D053204:Root Nodules, Plant / Q000235:genetics / Q000378:metabolism* / Q000382:microbiology; D017386:Sequence Homology, Amino Acid; D016962:Sinorhizobium meliloti / Q000254:growth & development; D013559:Symbiosis; D020798:Two-Hybrid System Techniques
chemical_list: D010940:Plant Proteins; D020033:Protein Isoforms; D008148:Lovastatin; D006903:Hydroxymethylglutaryl CoA Reductases