title: Histone H2B monoubiquitination is required to reach maximal transcript levels of circadian clock genes in Arabidopsis.
abstract: Previously, we identified HISTONE MONOUBIQUITINATION1 (HUB1) as an unconventional ubiquitin E3 ligase that is not involved in protein degradation but in the histone H2B modification that is implicated in transcriptional activation in plants. HUB1-mediated regulation of gene expression played a role in periodic and inducible processes such as the cell cycle, dormancy, flowering time and defense responses. Here, we determined the effects of the hub1-1 mutation on expression of a set of diurnally induced circadian clock genes identified from a comparative microarray analysis between the hub1-1 mutant and an HUB1 over-expression line. The hub1-1 mutation reduced the amplitudes of a number of induced clock gene expression peaks, as well as the HUB1-mediated histone H2BUb and H3K4Me3 marks associated with the coding regions, suggesting a role for HUB1 in facilitating transcriptional elongation in plants. Furthermore, double mutants between hub1-1 and elongata (elo) showed an embryo-lethal phenotype, indicating a synergistic genetic interaction. The double mutant embryos arrested at the torpedo stage, implying that together histone ubiquitination and acetylation marks are essential to activate expression of target genes in multiple pathways.
authors: Department of Plant Systems Biology, VIB, Technologiepark 927, 9052 Gent, Belgium.
authors: Kristiina
authors: K
authors: Himanen
authors: Magdalena
authors: M
authors: Woloszynska
authors: Tommaso M
authors: TM
authors: Boccardi
authors: Steven
authors: S
authors: De Groeve
authors: Hilde
authors: H
authors: Nelissen
authors: Leonardo
authors: L
authors: Bruno
authors: Marnik
authors: M
authors: Vuylsteke
authors: Mieke
authors: M
authors: Van Lijsebettens
mesh_terms: D000107:Acetylation; D017360:Arabidopsis / Q000196:embryology / Q000235:genetics* / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics*; D002843:Chromatin / Q000235:genetics; D057906:Circadian Clocks / Q000235:genetics*; D035264:Flowers / Q000196:embryology / Q000235:genetics / Q000502:physiology; D015870:Gene Expression; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant / Q000235:genetics*; D051548:Histone Acetyltransferases / Q000235:genetics; D006657:Histones / Q000235:genetics* / Q000378:metabolism; D046228:Microarray Analysis; D009154:Mutation; D016366:Open Reading Frames / Q000235:genetics; D018515:Plant Leaves / Q000196:embryology / Q000235:genetics / Q000502:physiology; D030821:Plants, Genetically Modified; D012333:RNA, Messenger / Q000235:genetics; D018749:RNA, Plant / Q000235:genetics; D036226:Seedlings / Q000196:embryology / Q000235:genetics / Q000502:physiology; D013997:Time Factors; D015533:Transcriptional Activation; D044767:Ubiquitin-Protein Ligases / Q000235:genetics; D054875:Ubiquitination
chemical_list: D029681:Arabidopsis Proteins; D002843:Chromatin; D006657:Histones; D012333:RNA, Messenger; D018749:RNA, Plant; C502551:ELO3 protein, Arabidopsis; D051548:Histone Acetyltransferases; C521255:HUB1 protein, Arabidopsis; D044767:Ubiquitin-Protein Ligases