title: Transcriptional repression of the APC/C activator CCS52A1 promotes active termination of cell growth.
abstract: Spatial and temporal control of cell growth is central for the morphogenesis of multicellular organisms. For some cell types that undergo extensive post-mitotic cell growth, such as neurons and hair cells, orchestrating the extent of post-mitotic cell growth with development is vital for their physiology and function. Previous studies suggested that the extent of cell growth is linked with an increase in ploidy by endoreduplication but how developmental signals control endocycling and cell growth is not understood in both animals and plants. In this study we show that a trihelix transcription factor, GT2-LIKE 1 (GTL1), actively terminates ploidy-dependent cell growth and its developmentally regulated expression is one of the key determinants of cell size in Arabidopsis leaf hair cells (trichomes). Through genome-wide chromatin-binding studies (ChIP-chip) coupled with transcriptional profiling, we further demonstrate that GTL1 directly represses the transcription of CDH1/FZR/CCS52, an activator of the anaphase-promoting complex/cyclosome (APC/C), to stop the endocycle progression and ploidy-dependent cell growth. Thus, our findings uncover a previously uncharacterised key molecular link between developmental programming and cell-size control, highlighting the central role of APC/C in post-mitotic cell growth.
authors.affiliation: RIKEN Plant Science Center, Yokohama, Kanagawa, Japan.
authors.forename: Christian
authors.initials: C
authors.lastname: Breuer
authors.forename: Kengo
authors.initials: K
authors.lastname: Morohashi
authors.forename: Ayako
authors.initials: A
authors.lastname: Kawamura
authors.forename: Naoki
authors.initials: N
authors.lastname: Takahashi
authors.forename: Takashi
authors.initials: T
authors.lastname: Ishida
authors.forename: Masaaki
authors.initials: M
authors.lastname: Umeda
authors.forename: Erich
authors.initials: E
authors.lastname: Grotewold
authors.forename: Keiko
authors.initials: K
authors.lastname: Sugimoto
mesh_terms: D064173:Anaphase-Promoting Complex-Cyclosome; D017360:Arabidopsis / Q000166:cytology / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000235:genetics*; D001483:Base Sequence; D018797:Cell Cycle Proteins / Q000235:genetics*; D048708:Cell Growth Processes / Q000235:genetics / Q000502:physiology*; D048429:Cell Size; D047369:Chromatin Immunoprecipitation; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant / Q000235:genetics / Q000502:physiology*; D046228:Microarray Analysis; D018613:Microscopy, Confocal; D008969:Molecular Sequence Data; D009841:Oligonucleotides / Q000235:genetics; D018515:Plant Leaves / Q000166:cytology; D010957:Plasmids / Q000235:genetics; D011003:Ploidies; D060888:Real-Time Polymerase Chain Reaction; D014157:Transcription Factors / Q000378:metabolism*; D020798:Two-Hybrid System Techniques; D043743:Ubiquitin-Protein Ligase Complexes / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D018797:Cell Cycle Proteins; C540491:FZR2 protein, Arabidopsis; D009841:Oligonucleotides; D014157:Transcription Factors; D043743:Ubiquitin-Protein Ligase Complexes; D064173:Anaphase-Promoting Complex-Cyclosome