title: A tomato (Solanum lycopersicum) APETALA2/ERF gene, SlAP2a, is a negative regulator of fruit ripening.
abstract: The transition of fleshy fruit maturation to ripening is regulated by exogenous and endogenous signals that coordinate the transition of the fruit to a final state of attractiveness to seed dispersing organisms. Tomato is a model for biology and genetics regulating specific ripening pathways including ethylene, carotenoids and cell wall metabolism in addition to upstream signaling and transcriptional regulators. Ripening-associated transcription factors described to date including the RIN-MADS, CLEAR NON-RIPENING, TAGL1 and LeHB-1 genes all encode positive regulators of ripening phenomena. Here we describe an APETALA2 transcription factor (SlAP2a) identified through transcriptional profiling of fruit maturation that is induced during, and which negatively regulates, tomato fruit ripening. RNAi repression of SlAP2a results in fruits that over-produce ethylene, ripen early and modify carotenoid accumulation profiles by altering carotenoid pathway flux. These results suggest that SlAP2a functions during normal tomato fruit ripening as a modulator of ripening activity and acts to balance the activities of positive ripening regulators.
authors.affiliation: Boyce Thompson Institute for Plant Research, Tower Road, Cornell University Campus, Ithaca, NY 14853, USA.
authors.forename: Mi-Young
authors.initials: MY
authors.lastname: Chung
authors.forename: Julia
authors.initials: J
authors.lastname: Vrebalov
authors.forename: Rob
authors.initials: R
authors.lastname: Alba
authors.forename: Jemin
authors.initials: J
authors.lastname: Lee
authors.forename: Ryan
authors.initials: R
authors.lastname: McQuinn
authors.forename: Jae-Dong
authors.initials: JD
authors.lastname: Chung
authors.forename: Patricia
authors.initials: P
authors.lastname: Klein
authors.forename: James
authors.initials: J
authors.lastname: Giovannoni
mesh_terms: D002338:Carotenoids / Q000096:biosynthesis; D005030:Ethylenes / Q000096:biosynthesis; D005638:Fruit / Q000254:growth & development*; D018506:Gene Expression Regulation, Plant; D005809:Genes, Regulator; D018551:Solanum lycopersicum / Q000235:genetics* / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified / Q000235:genetics / Q000378:metabolism; D034622:RNA Interference; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: D005030:Ethylenes; D010940:Plant Proteins; D014157:Transcription Factors; D002338:Carotenoids; C036216:ethylene