title: MIXTA-like transcription factors and WAX INDUCER1/SHINE1 coordinately regulate cuticle development in Arabidopsis and Torenia fournieri.
abstract: The waxy plant cuticle protects cells from dehydration, repels pathogen attack, and prevents organ fusion during development. The transcription factor WAX INDUCER1/SHINE1 (WIN1/SHN1) regulates the biosynthesis of waxy substances in Arabidopsis thaliana. Here, we show that the MIXTA-like MYB transcription factors MYB106 and MYB16, which regulate epidermal cell morphology, also regulate cuticle development coordinately with WIN1/SHN1 in Arabidopsis and Torenia fournieri. Expression of a MYB106 chimeric repressor fusion (35S:MYB106-SRDX) and knockout/down of MYB106 and MYB16 induced cuticle deficiencies characterized by organ adhesion and reduction of epicuticular wax crystals and cutin nanoridges. A similar organ fusion phenotype was produced by expression of a WIN1/SHN1 chimeric repressor. Conversely, the dominant active form of MYB106 (35S:MYB106-VP16) induced ectopic production of cutin nanoridges and increased expression of WIN1/SHN1 and wax biosynthetic genes. Microarray experiments revealed that MYB106 and WIN1/SHN1 regulate similar sets of genes, predominantly those involved in wax and cutin biosynthesis. Furthermore, WIN1/SHN1 expression was induced by MYB106-VP16 and repressed by MYB106-SRDX. These results indicate that the regulatory cascade of MIXTA-like proteins and WIN1/SHN1 coordinately regulate cutin biosynthesis and wax accumulation. This study reveals an additional key aspect of MIXTA-like protein function and suggests a unique relationship between cuticle development and epidermal cell differentiation.
authors.affiliation: Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology, Higashi 1-1-1, Tsukuba 305-8562, Japan.
authors.forename: Yoshimi
authors.initials: Y
authors.lastname: Oshima
authors.forename: Masahito
authors.initials: M
authors.lastname: Shikata
authors.forename: Tomotsugu
authors.initials: T
authors.lastname: Koyama
authors.forename: Norihiro
authors.initials: N
authors.lastname: Ohtsubo
authors.forename: Nobutaka
authors.initials: N
authors.lastname: Mitsuda
authors.forename: Masaru
authors.initials: M
authors.lastname: Ohme-Takagi
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D019684:Magnoliopsida / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D008563:Membrane Lipids / Q000378:metabolism; D008855:Microscopy, Electron, Scanning; D020411:Oligonucleotide Array Sequence Analysis; D010802:Phylogeny; D019441:Plant Epidermis / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D010940:Plant Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified; D034622:RNA Interference; D015534:Trans-Activators / Q000235:genetics* / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D059467:Transcriptome; D014885:Waxes / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; C585916:MYB16 protein, Arabidopsis; D008563:Membrane Lipids; D010940:Plant Proteins; D015534:Trans-Activators; D014157:Transcription Factors; C487812:WIN1 protein, Arabidopsis; D014885:Waxes; C000521:cutin