title: Cell differentiation and development in Arabidopsis are associated with changes in histone dynamics at the single-cell level.
abstract: The mechanism whereby the same genome can give rise to different cell types with different gene expression profiles is a fundamental problem in biology. Chromatin organization and dynamics have been shown to vary with altered gene expression in different cultured animal cell types, but there is little evidence yet from whole organisms linking chromatin dynamics with development. Here, we used both fluorescence recovery after photobleaching and two-photon photoactivation to show that in stem cells from Arabidopsis thaliana roots the mobility of the core histone H2B, as judged by exchange dynamics, is lower than in the surrounding cells of the meristem. However, as cells progress from meristematic to fully differentiated, core histones again become less mobile and more strongly bound to chromatin. We show that these transitions are largely mediated by changes in histone acetylation. We further show that altering histone acetylation levels, either in a mutant or by drug treatment, alters both the histone mobility and markers of development and differentiation. We propose that plant stem cells have relatively inactive chromatin, but they keep the potential to divide and differentiate into more dynamic states, and that these states are at least in part determined by histone acetylation levels.
authors.affiliation: Department of Cell and Developmental Biology, John Innes Centre, Norwich NR4 7UH, United Kingdom Plant Cell Biology Laboratory, Instituto de Tecnologia Quimica e Biologica, Universidade Nova de Lisboa, Oeiras 2781-901, Portugal.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Rosa
authors.affiliation: Department of Cell and Developmental Biology, John Innes Centre, Norwich NR4 7UH, United Kingdom School of Life Sciences, University of Warwick, Coventry CV4 7AL, United Kingdom.
authors.forename: Vardis
authors.initials: V
authors.lastname: Ntoukakis
authors.affiliation: Graduate School of Human Development and Environment, Kobe University, Kobe 657-8501, Japan.
authors.forename: Nobuko
authors.initials: N
authors.lastname: Ohmido
authors.affiliation: Department of Cell and Developmental Biology, John Innes Centre, Norwich NR4 7UH, United Kingdom.
authors.forename: Ali
authors.initials: A
authors.lastname: Pendle
authors.affiliation: Plant Cell Biology Laboratory, Instituto de Tecnologia Quimica e Biologica, Universidade Nova de Lisboa, Oeiras 2781-901, Portugal.
authors.forename: Rita
authors.initials: R
authors.lastname: Abranches
authors.affiliation: Department of Cell and Developmental Biology, John Innes Centre, Norwich NR4 7UH, United Kingdom peter.shaw@jic.ac.uk.
authors.forename: Peter
authors.initials: P
authors.lastname: Shaw
mesh_terms: D000107:Acetylation; D017360:Arabidopsis / Q000166:cytology / Q000235:genetics* / Q000254:growth & development; D002453:Cell Cycle / Q000235:genetics; D002454:Cell Differentiation / Q000235:genetics*; D044127:Epigenesis, Genetic; D036681:Fluorescence Recovery After Photobleaching; D018745:Genome, Plant; D006657:Histones / Q000378:metabolism*; D018517:Plant Roots / Q000166:cytology / Q000235:genetics / Q000254:growth & development
chemical_list: D006657:Histones