title: RNA-seq analysis of an apical meristem time series reveals a critical point in Arabidopsis thaliana flower initiation.
abstract: BACKGROUND
  Floral transition is a critical event in the life cycle of a flowering plant as it determines its reproductive success. Despite extensive studies of specific genes that regulate this process, the global changes in transcript expression profiles at the point when a vegetative meristem transitions into an inflorescence have not been reported. We analyzed gene expression during Arabidopsis thaliana meristem development under long day conditions from day 7 to 16 after germination in one-day increments.
  
  
  RESULTS
  The dynamics of the expression of the main flowering regulators was consistent with previous reports: notably, the expression of FLOWERING LOCUS C (FLC) decreased over the course of the time series while expression of LEAFY (LFY) increased. This analysis revealed a developmental time point between 10 and 12 days after germination where FLC expression had decreased but LFY expression had not yet increased, which was characterized by a peak in the number of differentially expressed genes. Gene Ontology (GO) enrichment analysis of these genes identified an overrepresentation of genes related to the cell cycle.
  
  
  CONCLUSIONS
  We discovered an unprecedented burst of differential expression of cell cycle related genes at one particular point during transition to flowering. We suggest that acceleration of rate of the divisions and partial cell cycling synchronization takes place at this point.
authors.affiliation: Institute for Information Transmission Problems of the Russian Academy of Sciences, Moscow, 127051, Russia. annklepikova@gmail.com.
authors.forename: Anna V
authors.initials: AV
authors.lastname: Klepikova
authors.affiliation: Institute for Information Transmission Problems of the Russian Academy of Sciences, Moscow, 127051, Russia. maria.log@gmail.com.|A. N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119991, Russia. maria.log@gmail.com.|Pirogov Russian National Research Medical University, 117997, Moscow, Russia. maria.log@gmail.com.
authors.forename: Maria D
authors.initials: MD
authors.lastname: Logacheva
authors.affiliation: A. N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119991, Russia. dmitriev_sergey@genebee.msu.su.|Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, 119991, Russia. dmitriev_sergey@genebee.msu.su.
authors.forename: Sergey E
authors.initials: SE
authors.lastname: Dmitriev
authors.affiliation: Institute for Information Transmission Problems of the Russian Academy of Sciences, Moscow, 127051, Russia. alekseypenin@gmail.com.|A. N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119991, Russia. alekseypenin@gmail.com.|Department of Genetics, Faculty of Biology, Lomonosov Moscow State University, Moscow, 119991, Russia. alekseypenin@gmail.com.
authors.forename: Aleksey A
authors.initials: AA
authors.lastname: Penin
mesh_terms: D017360:Arabidopsis / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000235:genetics; D002453:Cell Cycle / Q000235:genetics; D035264:Flowers / Q000235:genetics*; D018507:Gene Expression Regulation, Developmental / Q000235:genetics; D018506:Gene Expression Regulation, Plant / Q000235:genetics*; D017343:Genes, Plant / Q000235:genetics; D018525:Germination / Q000235:genetics; D056626:Inflorescence / Q000235:genetics; D018519:Meristem / Q000235:genetics*; D018515:Plant Leaves / Q000235:genetics; D018749:RNA, Plant / Q000235:genetics*; D017423:Sequence Analysis, RNA
chemical_list: D029681:Arabidopsis Proteins; D018749:RNA, Plant