title: A MYB coiled-coil transcription factor interacts with NSP2 and is involved in nodulation in Lotus japonicus.
abstract: Transcription factor complex formation is a central step in regulating gene expression. In this report, a novel MYB coiled-coil transcription factor referred to as IPN2, for Interacting Protein of NSP2, is described. The interaction between IPN2 and NSP2 was examined by protein pull-down assays and bimolecular fluorescence complementation (BiFC). Subcellular localization of proteins, gene expression and gene function were assessed in transgenic hairy roots expressing tagged recombinant proteins, promoter-reporter and RNA interference (RNAi) constructs, respectively. The GRAS domain of NSP2 and the coiled-coil domain of IPN2 were found to be responsible for the interaction between the two proteins. IPN2 had strong transcription activation activity, bound directly to the NIN gene promoter, and was localized to the nuclei of Lotus japonicus root cells. The expression of IPN2 was elevated during nodule development, coinciding with increased NSP2 gene expression during nodule organogenesis. RNAi-mediated knockdown expression of IPN2 did not affect arbuscular mycorrhizal development, but had deleterious effects on rhizobial infection and nodule formation in L. japonicus. These results demonstrate an important role of IPN2 in nodule organogenesis and place a new MYB transcription factor in the Nod signaling pathway.
authors.affiliation: State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China.
authors.forename: Heng
authors.initials: H
authors.lastname: Kang
authors.affiliation: State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China.
authors.forename: Xiaojie
authors.initials: X
authors.lastname: Chu
authors.affiliation: State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China.
authors.forename: Aifang
authors.initials: A
authors.lastname: Xiao
authors.affiliation: State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Zhu
authors.affiliation: State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China.
authors.forename: Songli
authors.initials: S
authors.lastname: Yuan
authors.affiliation: State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China.
authors.forename: Zhenzhen
authors.initials: Z
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China.
authors.forename: Danxia
authors.initials: D
authors.lastname: Ke
authors.affiliation: State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China.
authors.forename: Shaobo
authors.initials: S
authors.lastname: Xiao
authors.affiliation: Department of Plant, Soil, and Entomological Sciences, Program of Microbiology, Molecular Biology and Biochemistry, University of Idaho, Moscow, ID, 83844, USA.
authors.forename: Zonglie
authors.initials: Z
authors.lastname: Hong
authors.affiliation: State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, China.
authors.forename: Zhongming
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D000595:Amino Acid Sequence; D002467:Cell Nucleus / Q000378:metabolism; D018744:DNA, Plant / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D005966:Glucuronidase / Q000378:metabolism; D000070116:Lotus / Q000235:genetics / Q000382:microbiology / Q000502:physiology*; D008969:Molecular Sequence Data; D010641:Phenotype; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D055170:Plant Root Nodulation / Q000235:genetics; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D034622:RNA Interference; D012231:Rhizobium / Q000502:physiology; D053204:Root Nodules, Plant / Q000235:genetics / Q000382:microbiology; D013347:Subcellular Fractions / Q000378:metabolism; D013997:Time Factors; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015533:Transcriptional Activation / Q000235:genetics
chemical_list: D018744:DNA, Plant; D010940:Plant Proteins; D014157:Transcription Factors; D005966:Glucuronidase
keywords: Lotus japonicus; MYB protein; RNA interference; legume; nodulation; transcriptional regulation