title: The polycotyledon mutant of tomato shows enhanced polar auxin transport.
abstract: The polycotyledon mutant of tomato (Lycopersicon esculentum L. cv Ailsa Craig) showed altered development during embryogenesis and during vegetative and reproductive phases. The phenotype was pleiotropic and included the formation of extra cotyledons, changes in leaf shape, increased number of flowers (indeterminacy) with abnormal floral organs, the formation of epiphyllous structures, and altered gravitropism. The earliest defects were observed at the transition from the globular to the heart stage of embryogenesis with the formation of multiple cotyledons. Epidermal cells in the mutant embryo were smaller and less expanded compared with wild type. Examination of polar auxin transport (PAT) showed a striking enhancement in the case of the mutant. Increase in PAT did not appear to be caused by a decrease in flavonoids because the mutant had normal flavonoid levels. Application of 2,3,5-triiodobenzoic acid, an inhibitor of polar transport of auxin, rescued postgermination phenotypes of young seedlings. Our analysis reveals a level of control that negatively regulates PAT in tomato and its contribution to plant development and organogenesis.
authors.affiliation: School of Life Sciences, University of Hyderabad, Hyderabad-500046, India.
authors.forename: Arif S A
authors.initials: AS
authors.lastname: Al-Hammadi
authors.forename: Yellamaraju
authors.initials: Y
authors.lastname: Sreelakshmi
authors.forename: Sangeeta
authors.initials: S
authors.lastname: Negi
authors.forename: Imran
authors.initials: I
authors.lastname: Siddiqi
authors.forename: Rameshwar
authors.initials: R
authors.lastname: Sharma
mesh_terms: D001692:Biological Transport / Q000187:drug effects / Q000235:genetics; D048429:Cell Size / Q000235:genetics / Q000502:physiology; D018548:Cotyledon / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D035264:Flowers / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D018522:Gravitropism / Q000235:genetics / Q000502:physiology; D007210:Indoleacetic Acids / Q000378:metabolism*; D018551:Solanum lycopersicum / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D009154:Mutation; D010641:Phenotype; D018515:Plant Leaves / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D012639:Seeds / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D014283:Triiodobenzoic Acids / Q000494:pharmacology
chemical_list: D007210:Indoleacetic Acids; D014283:Triiodobenzoic Acids; C052968:2,3,5-triiodobenzoic acid