title: The Arabidopsis ABCG13 transporter is required for flower cuticle secretion and patterning of the petal epidermis.
abstract: Previous studies showed that ABCG11 and ABCG12, two ATP-binding-cassette (ABC) transporters, are required for cuticular lipids extracellular secretion. Here, we characterized ABCG13, a third clade member, to widen our limited knowledge regarding assembly of the plant's cuticle. We isolated an abcg13 knockout mutant and used RNAi and artificial microRNA approaches to study the effect of ABCG13 loss-of-function. These plants were subsequently used to conduct a detailed analysis of cuticular lipids composition and cytological observations. ABCG13 loss-of-function resulted in cuticle-related phenotypes that were restricted to flowers, including inter-organ post-genital fusions. Apart from a significant reduction in flower cutin monomers, the macromorphology and micromorphology of abcg13 petal epidermis was strongly affected. We also found that ABCG13 is highly expressed in flowers, predominantly in petals and carpels. The results suggest that ABCG13 is required for the transport of flower cuticular lipids. This work introduces a new component to the recently emerging genetic network that makes the archetypal exterior of Arabidopsis flowers. While the question regarding the substrate specificity of the ABCG12-clade members remains open, these findings will facilitate future investigations regarding the interaction between the half-size ABCG-type transporters that likely take part in cuticle assembly.
authors.affiliation: Department of Plant Sciences, Weizmann Institute of Science, PO Box 26, Rehovot 76100, Israel.
authors.forename: David
authors.initials: D
authors.lastname: Panikashvili
authors.affiliation: Department of Plant Sciences, Weizmann Institute of Science, PO Box 26, Rehovot 76100, Israel.
authors.forename: Jian Xin
authors.initials: JX
authors.lastname: Shi
authors.affiliation: Institute of Cellular and Molecular Botany (IZMB), Department of Ecophysiology, University of Bonn, Kirschallee 1, D-53115 Bonn, Germany.
authors.forename: Lukas
authors.initials: L
authors.lastname: Schreiber
authors.affiliation: Department of Plant Sciences, Weizmann Institute of Science, PO Box 26, Rehovot 76100, Israel.
authors.forename: Asaph
authors.initials: A
authors.lastname: Aharoni
mesh_terms: D000070996:ATP Binding Cassette Transporter, Subfamily G; D018528:ATP-Binding Cassette Transporters / Q000378:metabolism; D017360:Arabidopsis / Q000166:cytology / Q000378:metabolism* / Q000648:ultrastructure; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D015536:Down-Regulation; D035264:Flowers / Q000166:cytology / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D018506:Gene Expression Regulation, Plant; D035683:MicroRNAs / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D009928:Organ Specificity; D010641:Phenotype; D010802:Phylogeny; D019441:Plant Epidermis / Q000166:cytology / Q000378:metabolism* / Q000648:ultrastructure
chemical_list: C525930:ABCG11 protein, Arabidopsis; D000070996:ATP Binding Cassette Transporter, Subfamily G; D018528:ATP-Binding Cassette Transporters; D029681:Arabidopsis Proteins; D035683:MicroRNAs