title: Histone modification and signalling cascade of the dormancy-associated MADS-box gene, PpMADS13-1, in Japanese pear (Pyrus pyrifolia) during endodormancy.
abstract: Dormancy-associated MADS-box (DAM) genes play an important role in endodormancy phase transition. We investigated histone modification in the DAM homolog (PpMADS13-1) from Japanese pear, via chromatin immunoprecipitation-quantitative PCR, to understand the mechanism behind the reduced expression of the PpMADS13-1 gene towards endodormancy release. Our results indicated that the reduction in the active histone mark by trimethylation of the histone H3 tail at lysine 4 contributed to the reduction of PpMADS13-1 expression towards endodormancy release. In contrast, the inactive histone mark by trimethylation of the histone H3 tail at lysine 27 in PpMADS13-1 locus was quite low, and these levels were more similar to a negative control [normal mouse immunoglobulin G (IgG)] than to a positive control (AGAMOUS) in endodormancy phase transition. The loss of histone variant H2A.Z also coincided with the down-regulation of PpMADS13-1. Subsequently, we investigated the PpMADS13-1 signalling cascade and found that PpCBF2, a pear C-repeated binding factor, regulated PpMADS13-1 expression via interaction of PpCBF2 with the 5'-upstream region of PpMADS13-1 by transient reporter assay. Furthermore, transient reporter assay confirmed no interaction between the PpMADS13-1 protein and the pear FLOWERING LOCUS T genes. Taken together, our results enhance understanding of the molecular mechanisms underlying endodormancy phase transition in Japanese pear.
authors.affiliation: Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, 305-8572, Japan; NARO Institute of Fruit Tree Science, Tsukuba, Ibaraki, 305-8605, Japan.
authors.forename: Takanori
authors.initials: T
authors.lastname: Saito
authors.forename: Songling
authors.initials: S
authors.lastname: Bai
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Imai
authors.forename: Akiko
authors.initials: A
authors.lastname: Ito
authors.forename: Ikuko
authors.initials: I
authors.lastname: Nakajima
authors.forename: Takaya
authors.initials: T
authors.lastname: Moriguchi
mesh_terms: D047369:Chromatin Immunoprecipitation; D015536:Down-Regulation; D018506:Gene Expression Regulation, Plant / Q000235:genetics / Q000502:physiology; D017343:Genes, Plant / Q000235:genetics / Q000502:physiology*; D042421:Histone Code / Q000235:genetics / Q000502:physiology*; D026161:MADS Domain Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D057445:Plant Dormancy / Q000235:genetics / Q000502:physiology*; D010940:Plant Proteins / Q000235:genetics / Q000502:physiology*; D031989:Pyrus / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000502:physiology
chemical_list: D026161:MADS Domain Proteins; D010940:Plant Proteins
keywords: C-repeat binding factor (CBF) gene; FLOWERING LOCUS T (FT) gene; Japanese pear (Pyrus pyrifolia Nakai)