title: The SNARE protein SYP71 expressed in vascular tissues is involved in symbiotic nitrogen fixation in Lotus japonicus nodules.
abstract: Soluble N-Ethylmaleimide Sensitive Factor Attachment Protein Receptor (SNARE) proteins are crucial for signal transduction and development in plants. Here, we investigate a Lotus japonicus symbiotic mutant defective in one of the SNARE proteins. When in symbiosis with rhizobia, the growth of the mutant was retarded compared with that of the wild-type plant. Although the mutant formed nodules, these exhibited lower nitrogen fixation activity than the wild type. The rhizobia were able to invade nodule cells, but enlarged symbiosomes were observed in the infected cells. The causal gene, designated LjSYP71 (for L. japonicus syntaxin of plants71), was identified by map-based cloning and shown to encode a Qc-SNARE protein homologous to Arabidopsis (Arabidopsis thaliana) SYP71. LjSYP71 was expressed ubiquitously in shoot, roots, and nodules, and transcripts were detected in the vascular tissues. In the mutant, no other visible defects in plant morphology were observed. Furthermore, in the presence of combined nitrogen, the mutant plant grew almost as well as the wild type. These results suggest that the vascular tissues expressing LjSYP71 play a pivotal role in symbiotic nitrogen fixation in L. japonicus nodules.
authors.affiliation: National Institute of Agrobiological Sciences, Tsukuba, Ibaraki 305-8602, Japan.
authors.forename: Tsuneo
authors.initials: T
authors.lastname: Hakoyama
authors.forename: Ryo
authors.initials: R
authors.lastname: Oi
authors.forename: Kazuya
authors.initials: K
authors.lastname: Hazuma
authors.forename: Eri
authors.initials: E
authors.lastname: Suga
authors.forename: Yuka
authors.initials: Y
authors.lastname: Adachi
authors.forename: Mayumi
authors.initials: M
authors.lastname: Kobayashi
authors.forename: Rie
authors.initials: R
authors.lastname: Akai
authors.forename: Shusei
authors.initials: S
authors.lastname: Sato
authors.forename: Eigo
authors.initials: E
authors.lastname: Fukai
authors.forename: Satoshi
authors.initials: S
authors.lastname: Tabata
authors.forename: Satoshi
authors.initials: S
authors.lastname: Shibata
authors.forename: Guo-Jiang
authors.initials: GJ
authors.lastname: Wu
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Hase
authors.forename: Atsushi
authors.initials: A
authors.lastname: Tanaka
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Kawaguchi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kouchi
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Umehara
authors.forename: Norio
authors.initials: N
authors.lastname: Suganuma
mesh_terms: D002874:Chromosome Mapping; D003001:Cloning, Molecular; D003433:Crosses, Genetic; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D005816:Genetic Complementation Test; D000070116:Lotus / Q000235:genetics / Q000378:metabolism* / Q000382:microbiology; D059128:Mesorhizobium / Q000254:growth & development; D046529:Microscopy, Electron, Transmission; D016296:Mutagenesis; D009586:Nitrogen Fixation; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D018520:Plant Shoots / Q000235:genetics / Q000378:metabolism; D058526:Plant Vascular Bundle / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified / Q000235:genetics / Q000378:metabolism / Q000382:microbiology; D050767:Qc-SNARE Proteins / Q000235:genetics / Q000378:metabolism*; D053204:Root Nodules, Plant / Q000235:genetics / Q000378:metabolism / Q000382:microbiology; D013559:Symbiosis
chemical_list: D010940:Plant Proteins; D050767:Qc-SNARE Proteins