title: Interactions between gene activity and cell layers during floral development.
abstract: The DEFICIENS (DEF) gene is required for establishing petal and stamen identity in Antirrhinum and is expressed in all three layers of the floral meristem in whorls 2 and 3. Expression of DEF in a subset of meristem layers gives rise to organs with characteristic shapes and cell types, reflecting altered patterns and levels of DEF gene activity. To determine how the contributions of layers and gene activity interact, we exploited a DEF allele which carries a transposon insertion in the MADS box region to generate periclinal chimeras expressing alleles with different activities. By comparing the phenotype, development and expression patterns of these chimeras we show that expression of DEF in L1 makes a major contribution to morphology in whorl 2, irrespective of the allele. By contrast L1 expression is largely unable to rescue whorl 3, possibly because of a non-autonomous inhibitor of DEF activity in this whorl.
authors.affiliation: John Innes Centre, Colney Lane, Norwich NR4 7UH, UK.
authors.forename: Coral A
authors.initials: CA
authors.lastname: Vincent
authors.forename: Rosemary
authors.initials: R
authors.lastname: Carpenter
authors.forename: Enrico S
authors.initials: ES
authors.lastname: Coen
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D032161:Antirrhinum / Q000235:genetics* / Q000254:growth & development / Q000648:ultrastructure; D001483:Base Sequence; D026281:DEFICIENS Protein / Q000235:genetics* / Q000378:metabolism; D004251:DNA Transposable Elements / Q000235:genetics; D035264:Flowers / Q000235:genetics* / Q000254:growth & development / Q000648:ultrastructure; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D017403:In Situ Hybridization; D018519:Meristem / Q000235:genetics* / Q000254:growth & development / Q000648:ultrastructure; D008855:Microscopy, Electron, Scanning; D009154:Mutation; D010641:Phenotype; D019441:Plant Epidermis / Q000235:genetics / Q000254:growth & development / Q000648:ultrastructure; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D026281:DEFICIENS Protein; D004251:DNA Transposable Elements; C083654:FLO protein, Antirrhinum majus; C102172:GLOBOSA protein, plant; D018398:Homeodomain Proteins; D010940:Plant Proteins