title: Asymmetric leaf development and blade expansion in Arabidopsis are mediated by KANADI and YABBY activities.
abstract: Asymmetric development of plant lateral organs is initiated by a partitioning of organ primordia into distinct domains along their adaxial/abaxial axis. Two primary determinants of abaxial cell fate are members of the KANADI and YABBY gene families. Progressive loss of KANADI activity in loss-of-function mutants results in progressive transformation of abaxial cell types into adaxial ones and a correlated loss of lamina formation. Novel, localized planes of blade expansion occur in some kanadi loss-of-function genotypes and these ectopic lamina outgrowths are YABBY dependent. We propose that the initial asymmetric leaf development is regulated primarily by mutual antagonism between KANADI and PHB-like genes, which is translated into polar YABBY expression. Subsequently, polar YABBY expression contributes both to abaxial cell fate and to abaxial/adaxial juxtaposition-mediated lamina expansion.
authors.affiliation: Section of Plant Biology, Division of Biological Sciences, University of California, One Shields Avenue, Davis, CA 95616, USA.
authors.forename: Yuval
authors.initials: Y
authors.lastname: Eshed
authors.forename: Anat
authors.initials: A
authors.lastname: Izhaki
authors.forename: Stuart F
authors.initials: SF
authors.lastname: Baum
authors.forename: Sandra K
authors.initials: SK
authors.lastname: Floyd
authors.forename: John L
authors.initials: JL
authors.lastname: Bowman
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D019656:Loss of Heterozygosity; D016296:Mutagenesis; D018515:Plant Leaves / Q000235:genetics / Q000254:growth & development*; D018547:Plant Stems / Q000235:genetics / Q000254:growth & development; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; C430846:KANADI protein, Arabidopsis; D014157:Transcription Factors; C121842:YABBY3 protein, Arabidopsis