title: The Arabidopsis 3-ketoacyl-CoA thiolase-2 (kat2-1) mutant exhibits increased flowering but reduced reproductive success.
abstract: The enzyme 3-ketoacyl-CoA thiolase (KAT) (EC 2.3.1.16) catalyses a key step in fatty acid beta-oxidation. In Arabidopsis thaliana, expression of the KAT2 gene is known to be required for the efficient mobilization of triacylglycerol during germination and seedling establishment. Here, data from the Arabidopsis kat2-1 mutant are presented, showing that perturbation of beta-oxidation also affects vegetative growth and reproductive success. In the wild type, the KAT2 protein was detected in all organs tested. In the kat2-1 mutant, rosette leaf area and dry weight, but not leaf number, were greatly increased relative to wild type. Global proliferative arrest of flowering was delayed, resulting in increased silique production in kat2-1 plants. However, total silique dry weight was not increased. kat2-1 siliques were smaller and had a reduced seed number caused by increased ovule abortion. In kat2-1 ovules, carbon flow into sugars via gluconeogeneis and respiration were both reduced in comparison to the wild type. In conclusion, these data indicate that a functional beta-oxidation pathway is required to maintain the balance between silique development and the continued initiation of floral meristems.
authors.affiliation: Institute of Cell and Molecular Biology, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JH, UK. S.Footitt@warwick.ac.uk
authors.forename: Steven
authors.initials: S
authors.lastname: Footitt
authors.forename: Johanna E
authors.initials: JE
authors.lastname: Cornah
authors.forename: Itsara
authors.initials: I
authors.lastname: Pracharoenwattana
authors.forename: James H
authors.initials: JH
authors.lastname: Bryce
authors.forename: Steven M
authors.initials: SM
authors.lastname: Smith
mesh_terms: D000102:Acetyl-CoA C-Acyltransferase / Q000235:genetics*; D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics*; D002244:Carbon / Q000378:metabolism; D035264:Flowers / Q000235:genetics / Q000254:growth & development; D009154:Mutation; D010641:Phenotype; D018515:Plant Leaves / Q000235:genetics / Q000254:growth & development; D012098:Reproduction / Q000235:genetics
chemical_list: D000102:Acetyl-CoA C-Acyltransferase; D029681:Arabidopsis Proteins; D002244:Carbon; C526106:PKT3 protein, Arabidopsis