title: Spatially selective hormonal control of RAP2.6L and ANAC071 transcription factors involved in tissue reunion in Arabidopsis.
abstract: When grafting or wounding disconnects stem tissues, new tissues are generated to restore the lost connection. In this study, the molecular mechanism of such healing was elucidated in injured stems of Arabidopsis. Soon after the inflorescence stems were incised, the pith cells started to divide. This process was strongly inhibited by the elimination of cauline leaves, shoot apices, or lateral buds that reduced the indole-3-acetic acid supply. Microarray and quantitative RT-PCR analyses revealed that genes related to cell division, phytohormones, and transcription factors were expressed because of incision. Among them, two plant-specific transcription factor genes, ANAC071 and RAP2.6L, were abundantly expressed. ANAC071 was expressed at 1-3 d after cutting exclusively in the upper region of the cut gap, with concomitant accumulation of indole-3-acetic acid. In contrast, RAP2.6L was expressed at 1 d after cutting exclusively in the lower region, with concomitant deprivation of indole-3-acetic acid. The expression of ANAC071 and RAP2.6L were also promoted by ethylene and jasmonic acid, respectively. In transformants suppressing the function of RAP2.6L or ANAC071, the division of pith cells was inhibited. Furthermore, the ethylene signaling-defective ein2 mutant showed incomplete healing. Hence, plant-specific transcription factors differentially expressed around the cut position were essential for tissue reunion of Arabidopsis wounded flowering stems and were under opposite control by polar-transported auxin, with modification by the ethylene and jasmonic acid wound-inducible hormones.
authors.affiliation: Department of Biosciences, Teikyo University, Utsunomiya, Tochigi 320-8551, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Asahina
authors.forename: Katsuya
authors.initials: K
authors.lastname: Azuma
authors.forename: Weerasak
authors.initials: W
authors.lastname: Pitaksaringkarn
authors.forename: Takashi
authors.initials: T
authors.lastname: Yamazaki
authors.forename: Nobutaka
authors.initials: N
authors.lastname: Mitsuda
authors.forename: Masaru
authors.initials: M
authors.lastname: Ohme-Takagi
authors.forename: Shinjiro
authors.initials: S
authors.lastname: Yamaguchi
authors.forename: Yuji
authors.initials: Y
authors.lastname: Kamiya
authors.forename: Kiyotaka
authors.initials: K
authors.lastname: Okada
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nishimura
authors.forename: Tomokazu
authors.initials: T
authors.lastname: Koshiba
authors.forename: Takao
authors.initials: T
authors.lastname: Yokota
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kamada
authors.forename: Shinobu
authors.initials: S
authors.lastname: Satoh
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics*; D003517:Cyclopentanes / Q000494:pharmacology; D005030:Ethylenes / Q000494:pharmacology; D035264:Flowers / Q000235:genetics / Q000378:metabolism; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D007210:Indoleacetic Acids / Q000378:metabolism / Q000494:pharmacology; D020411:Oligonucleotide Array Sequence Analysis; D054883:Oxylipins / Q000494:pharmacology; D010937:Plant Growth Regulators / Q000494:pharmacology; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism; D018547:Plant Stems / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors; D014157:Transcription Factors / Q000235:genetics*; D059467:Transcriptome
chemical_list: C568459:ANAC071 protein, Arabidopsis; D029681:Arabidopsis Proteins; D003517:Cyclopentanes; D005030:Ethylenes; C483307:IAA5 protein, Arabidopsis; D007210:Indoleacetic Acids; D054883:Oxylipins; D010937:Plant Growth Regulators; C555644:RAP2.6L protein, Arabidopsis; D014157:Transcription Factors; C011006:jasmonic acid; C030737:indoleacetic acid; C036216:ethylene