title: Plant peptides govern terminal differentiation of bacteria in symbiosis.
abstract: Legume plants host nitrogen-fixing endosymbiotic Rhizobium bacteria in root nodules. In Medicago truncatula, the bacteria undergo an irreversible (terminal) differentiation mediated by hitherto unidentified plant factors. We demonstrated that these factors are nodule-specific cysteine-rich (NCR) peptides that are targeted to the bacteria and enter the bacterial membrane and cytosol. Obstruction of NCR transport in the dnf1-1 signal peptidase mutant correlated with the absence of terminal bacterial differentiation. On the contrary, ectopic expression of NCRs in legumes devoid of NCRs or challenge of cultured rhizobia with peptides provoked symptoms of terminal differentiation. Because NCRs resemble antimicrobial peptides, our findings reveal a previously unknown innovation of the host plant, which adopts effectors of the innate immune system for symbiosis to manipulate the cell fate of endosymbiotic bacteria.
authors.affiliation: Institut des Sciences du Végétal, Centre National de la Recherche Scientifique, 91198 Gif-sur-Yvette Cedex, France.
authors.forename: Willem
authors.initials: W
authors.lastname: Van de Velde
authors.forename: Grigor
authors.initials: G
authors.lastname: Zehirov
authors.forename: Agnes
authors.initials: A
authors.lastname: Szatmari
authors.forename: Monika
authors.initials: M
authors.lastname: Debreczeny
authors.forename: Hironobu
authors.initials: H
authors.lastname: Ishihara
authors.forename: Zoltan
authors.initials: Z
authors.lastname: Kevei
authors.forename: Attila
authors.initials: A
authors.lastname: Farkas
authors.forename: Kata
authors.initials: K
authors.lastname: Mikulass
authors.forename: Andrea
authors.initials: A
authors.lastname: Nagy
authors.forename: Hilda
authors.initials: H
authors.lastname: Tiricz
authors.forename: Beatrice
authors.initials: B
authors.lastname: Satiat-Jeunemaître
authors.forename: Benoit
authors.initials: B
authors.lastname: Alunni
authors.forename: Mickael
authors.initials: M
authors.lastname: Bourge
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Kucho
authors.forename: Mikiko
authors.initials: M
authors.lastname: Abe
authors.forename: Attila
authors.initials: A
authors.lastname: Kereszt
authors.forename: Gergely
authors.initials: G
authors.lastname: Maroti
authors.forename: Toshiki
authors.initials: T
authors.lastname: Uchiumi
authors.forename: Eva
authors.initials: E
authors.lastname: Kondorosi
authors.forename: Peter
authors.initials: P
authors.lastname: Mergaert
mesh_terms: D000595:Amino Acid Sequence; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002455:Cell Division; D002462:Cell Membrane / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism; D017343:Genes, Plant; D000070116:Lotus / Q000235:genetics / Q000378:metabolism / Q000382:microbiology; D046913:Medicago truncatula / Q000235:genetics / Q000378:metabolism* / Q000382:microbiology*; D008969:Molecular Sequence Data; D009586:Nitrogen Fixation; D010455:Peptides / Q000737:chemistry / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified; D021381:Protein Transport; D053204:Root Nodules, Plant / Q000378:metabolism / Q000382:microbiology; D016962:Sinorhizobium meliloti / Q000166:cytology* / Q000187:drug effects / Q000502:physiology*; D013559:Symbiosis
chemical_list: D000900:Anti-Bacterial Agents; D010455:Peptides; D010940:Plant Proteins