title: A novel aux/IAA28 signaling cascade activates GATA23-dependent specification of lateral root founder cell identity.
abstract: BACKGROUND
  Lateral roots are formed at regular intervals along the main root by recurrent specification of founder cells. To date, the mechanism by which branching of the root system is controlled and founder cells become specified remains unknown.
  
  
  RESULTS
  Our study reports the identification of the auxin regulatory components and their target gene, GATA23, which control lateral root founder cell specification. Initially, a meta-analysis of lateral root-related transcriptomic data identified the GATA23 transcription factor. GATA23 is expressed specifically in xylem pole pericycle cells before the first asymmetric division and is correlated with oscillating auxin signaling maxima in the basal meristem. Also, functional studies revealed that GATA23 controls lateral root founder cell identity. Finally, we show that an Aux/IAA28-dependent auxin signaling mechanism in the basal meristem controls GATA23 expression.
  
  
  CONCLUSIONS
  We have identified the first molecular components that control lateral root founder cell identity in the Arabidopsis root. These include an IAA28-dependent auxin signaling module in the basal meristem region that regulates GATA23 expression and thereby lateral root founder cell specification and root branching patterns.
authors.affiliation: Department of Plant Systems Biology, VIB, Technologiepark 927, B-9052 Ghent, Belgium.
authors.forename: Bert
authors.initials: B
authors.lastname: De Rybel
authors.forename: Valya
authors.initials: V
authors.lastname: Vassileva
authors.forename: Boris
authors.initials: B
authors.lastname: Parizot
authors.forename: Marlies
authors.initials: M
authors.lastname: Demeulenaere
authors.forename: Wim
authors.initials: W
authors.lastname: Grunewald
authors.forename: Dominique
authors.initials: D
authors.lastname: Audenaert
authors.forename: Jelle
authors.initials: J
authors.lastname: Van Campenhout
authors.forename: Paul
authors.initials: P
authors.lastname: Overvoorde
authors.forename: Leentje
authors.initials: L
authors.lastname: Jansen
authors.forename: Steffen
authors.initials: S
authors.lastname: Vanneste
authors.forename: Barbara
authors.initials: B
authors.lastname: Möller
authors.forename: Michael
authors.initials: M
authors.lastname: Wilson
authors.forename: Tara
authors.initials: T
authors.lastname: Holman
authors.forename: Gert
authors.initials: G
authors.lastname: Van Isterdael
authors.forename: Géraldine
authors.initials: G
authors.lastname: Brunoud
authors.forename: Marnik
authors.initials: M
authors.lastname: Vuylsteke
authors.forename: Teva
authors.initials: T
authors.lastname: Vernoux
authors.forename: Lieven
authors.initials: L
authors.lastname: De Veylder
authors.forename: Dirk
authors.initials: D
authors.lastname: Inzé
authors.forename: Dolf
authors.initials: D
authors.lastname: Weijers
authors.forename: Malcolm J
authors.initials: MJ
authors.lastname: Bennett
authors.forename: Tom
authors.initials: T
authors.lastname: Beeckman
mesh_terms: D050980:GATA Transcription Factors / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D007210:Indoleacetic Acids / Q000378:metabolism*; D008969:Molecular Sequence Data; D063245:Plant Development; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D018517:Plant Roots / Q000166:cytology / Q000254:growth & development*; D010944:Plants / Q000033:anatomy & histology / Q000235:genetics; D015398:Signal Transduction; D020798:Two-Hybrid System Techniques
chemical_list: D050980:GATA Transcription Factors; D007210:Indoleacetic Acids; D010940:Plant Proteins