title: JOINTLESS is a MADS-box gene controlling tomato flower abscission zone development.
abstract: Abscission is a universal and dynamic process in plants whereby organs such as leaves, flowers and fruit are shed, both during normal development, and in response to tissue damage and stress. Shedding occurs by separation of cells in anatomically distinct regions of the plant, called abscission zones (AZs). During abscission, the plant hormone ethylene stimulates cells to produce enzymes that degrade the middle lamella between cells in the AZ. The physiology and regulation of abscission at fully developed AZs is well known, but the molecular biology underlying their development is not. Here we report the first isolation of a gene directly involved in the development of a functional plant AZ. Tomato plants with the jointless mutation fail to develop AZs on their pedicels and so abscission of flowers or fruit does not occur normally. We identify JOINTLESS as a new MADS-box gene in a distinct phylogenetic clade separate from those functioning in floral organs. We propose that a deletion in JOINTLESS accounts for the failure of activation of pedicel AZ development in jointless tomato plants.
authors.affiliation: Clemson University Genomics Institute, South Carolina 29634, USA.
authors.forename: L
authors.initials: L
authors.lastname: Mao
authors.forename: D
authors.initials: D
authors.lastname: Begum
authors.forename: H W
authors.initials: HW
authors.lastname: Chuang
authors.forename: M A
authors.initials: MA
authors.lastname: Budiman
authors.forename: E J
authors.initials: EJ
authors.lastname: Szymkowiak
authors.forename: E E
authors.initials: EE
authors.lastname: Irish
authors.forename: R A
authors.initials: RA
authors.lastname: Wing
mesh_terms: D003001:Cloning, Molecular; D017124:Conserved Sequence; D018076:DNA, Complementary; D018744:DNA, Plant; D004268:DNA-Binding Proteins / Q000235:genetics*; D017343:Genes, Plant; D018551:Solanum lycopersicum / Q000235:genetics* / Q000254:growth & development; D026161:MADS Domain Proteins; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics*; D018514:Plant Structures / Q000254:growth & development; D030821:Plants, Genetically Modified; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D014157:Transcription Factors / Q000235:genetics*
chemical_list: D018076:DNA, Complementary; D018744:DNA, Plant; D004268:DNA-Binding Proteins; C118233:J protein, Lycopersicon esculentum; D026161:MADS Domain Proteins; D010940:Plant Proteins; D014157:Transcription Factors