title: A bHLH complex controls embryonic vascular tissue establishment and indeterminate growth in Arabidopsis.
abstract: Plants have a remarkable potential for sustained (indeterminate) postembryonic growth. Following their specification in the early embryo, tissue-specific precursor cells first establish tissues and later maintain them postembryonically. The mechanisms underlying these processes are largely unknown. Here we define local control of oriented, periclinal cell division as the mechanism underlying both the establishment and maintenance of vascular tissue. We identify an auxin-regulated basic helix-loop-helix (bHLH) transcription factor dimer as a critical regulator of vascular development. Due to a loss of periclinal divisions, vascular tissue gradually disappears in bHLH-deficient mutants; conversely, ectopic expression is sufficient for triggering periclinal divisions. We show that this dimer operates independently of tissue identity but is restricted to a small vascular domain by integrating overlapping transcription patterns of the interacting bHLH proteins. Our work reveals a common mechanism for tissue establishment and indeterminate vascular development and provides a conceptual framework for developmental control of local cell divisions.
authors: Laboratory of Biochemistry, Wageningen University, Dreijenlaan 3, 6703HA Wageningen, The Netherlands.
authors: Bert
authors: B
authors: De Rybel
authors: Barbara
authors: B
authors: Möller
authors: Saiko
authors: S
authors: Yoshida
authors: Ilona
authors: I
authors: Grabowicz
authors: Pierre
authors: P
authors: Barbier de Reuille
authors: Sjef
authors: S
authors: Boeren
authors: Richard S
authors: RS
authors: Smith
authors: Jan Willem
authors: JW
authors: Borst
authors: Dolf
authors: D
authors: Weijers
mesh_terms: D017360:Arabidopsis / Q000196:embryology* / Q000235:genetics / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D051792:Basic Helix-Loop-Helix Proteins / Q000235:genetics / Q000378:metabolism*; D015153:Blotting, Western; D002454:Cell Differentiation; D002455:Cell Division; D031541:Fluorescence Resonance Energy Transfer; D018506:Gene Expression Regulation, Plant; D047468:Immunoprecipitation; D007210:Indoleacetic Acids / Q000494:pharmacology; D018519:Meristem / Q000166:cytology*; D009154:Mutation / Q000235:genetics; D063245:Plant Development / Q000187:drug effects / Q000502:physiology*; D030821:Plants, Genetically Modified / Q000196:embryology / Q000235:genetics / Q000378:metabolism; D055503:Protein Multimerization; D017434:Protein Structure, Tertiary; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D029681:Arabidopsis Proteins; D051792:Basic Helix-Loop-Helix Proteins; D007210:Indoleacetic Acids; D012333:RNA, Messenger