title: Histone acetylation affects expression of cellular patterning genes in the Arabidopsis root epidermis.
abstract: The Arabidopsis root has a unique cellular pattern in its single-layered epidermis. Cells residing over the intercellular spaces between underlying cortical cells (H position) differentiate into hair cells, whereas those directly over cortical cells (N position) differentiate into non-hair cells. Recent studies have revealed that this cellular pattern is determined by interactions of six patterning genes CPC, ETC, GL2, GL3/EGL3, TTG, and WER, and that the position-dependent expression of the CPC, GL2, and WER genes is essential for their appropriate interactions. However, little is known about how the expressions of the pattern genes are determined. Here we show that trichostatin A (TSA) treatment of germinating Arabidopsis seedlings alters the cellular pattern of the root epidermis to induce hair cell development at nonhair positions. The effects of TSA treatment are rapid, reversible, concentration-dependent, and position-independent. TSA inhibition of histone deacetylase activity results in hyperacetylation of the core histones H3 and H4, and alters the expression levels and cell specific expression of the patterning genes CPC, GL2 and WER. Analysis of histone deacetylase mutant cellular patterning further verified the participation of histone acetylation in cellular patterning, and revealed that HDA18 is a key component in the regulatory machinery of the Arabidopsis root epidermis. We propose a working model to suggest that histone acetylation may function in mediating a positional cue to direct expression of the patterning genes in the root epidermal cells.
authors.affiliation: PKU-Yale Joint Research Center of Agricultural and Plant Molecular Biology, National Key Laboratory of Protein Engineering and Plant Gene Engineering, College of Life Sciences, Peking University, Beijing 100871, China.
authors.forename: Cheng-Ran
authors.initials: CR
authors.lastname: Xu
authors.forename: Cui
authors.initials: C
authors.lastname: Liu
authors.forename: Yi-Lan
authors.initials: YL
authors.lastname: Wang
authors.forename: Lin-Chen
authors.initials: LC
authors.lastname: Li
authors.forename: Wen-Qian
authors.initials: WQ
authors.lastname: Chen
authors.forename: Zhi-Hong
authors.initials: ZH
authors.lastname: Xu
authors.forename: Shu-Nong
authors.initials: SN
authors.lastname: Bai
mesh_terms: D017360:Arabidopsis / Q000254:growth & development / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D047369:Chromatin Immunoprecipitation; D018506:Gene Expression Regulation, Plant / Q000187:drug effects / Q000502:physiology*; D056572:Histone Deacetylase Inhibitors; D006657:Histones / Q000378:metabolism*; D006877:Hydroxamic Acids / Q000494:pharmacology; D017403:In Situ Hybridization; D008954:Models, Biological; D009024:Morphogenesis / Q000502:physiology*; D019441:Plant Epidermis / Q000378:metabolism*; D018517:Plant Roots / Q000166:cytology / Q000254:growth & development*; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D029681:Arabidopsis Proteins; D056572:Histone Deacetylase Inhibitors; D006657:Histones; D006877:Hydroxamic Acids; C012589:trichostatin A