title: The rotunda2 mutants identify a role for the LEUNIG gene in vegetative leaf morphogenesis.
abstract: Leaf development in Arabidopsis thaliana is considered to be a two-step process. In the first step, a leaf primordium is formed that involves a switch from indeterminate to leaf developmental fate in the shoot apical meristem cells. The second step, known as leaf morphogenesis, consists of post-initiation developmental events such as patterned cell proliferation, cell expansion, and cell differentiation. The results are presented of the molecular and genetic analyses of the rotunda2 (ron2) mutants of Arabidopsis, which were isolated based on their wide and serrated vegetative leaf lamina. The RON2 gene was positionally cloned and was identical to LEUNIG (LUG); it encodes a transcriptional co-repressor that has been described to affect flower development. Morphological and histological analyses of expanded leaves indicated that RON2 (LUG) acts at later stages of leaf development by restricting cell expansion during leaf growth. Real-time reverse-transcription polymerase chain reaction was used to quantify the expression of KNOX, WUSCHEL, YABBY3, LEAFY, ASYMMETRIC LEAVES, and GIBBERELLIN OXIDASE genes in expanding and fully expanded rosette leaf laminas of the wild type and ron2 and lug mutants. SHOOTMERISTEMLESS was expressed in wild-type leaves and down-regulated in the mutants. The results indicate that RON2 (LUG) has a function in later stages of leaf development.
authors.affiliation: Department of Plant Systems Biology, Flanders Interuniversity Institute for Biotechnology, Ghent University, Technologiepark 927, B-9052 Ghent, Belgium.
authors.forename: Gerda
authors.initials: G
authors.lastname: Cnops
authors.forename: Sara
authors.initials: S
authors.lastname: Jover-Gil
authors.forename: Janny L
authors.initials: JL
authors.lastname: Peters
authors.forename: Pia
authors.initials: P
authors.lastname: Neyt
authors.forename: Sabine
authors.initials: S
authors.lastname: De Block
authors.forename: Pedro
authors.initials: P
authors.lastname: Robles
authors.forename: María R
authors.initials: MR
authors.lastname: Ponce
authors.forename: Tom
authors.initials: T
authors.lastname: Gerats
authors.forename: José L
authors.initials: JL
authors.lastname: Micol
authors.forename: Mieke
authors.initials: M
authors.lastname: Van Lijsebettens
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000166:cytology / Q000235:genetics / Q000254:growth & development*; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000235:genetics*; D048429:Cell Size; D032461:Chromosomes, Plant / Q000235:genetics; D017124:Conserved Sequence; D017931:DNA Primers; D008857:Microscopy, Interference / Q000379:methods; D008969:Molecular Sequence Data; D009024:Morphogenesis; D012275:Oryza / Q000235:genetics; D010641:Phenotype; D018515:Plant Leaves / Q000235:genetics / Q000254:growth & development*; D015183:Restriction Mapping; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics*
chemical_list: D029681:Arabidopsis Proteins; D017931:DNA Primers; C417768:LUG protein, Arabidopsis; D014157:Transcription Factors