Contrasting dynamics in abscisic acid metabolism in different Fragaria spp. during fruit ripening and identification of the enzymes involved. (1st November 2020)

• Record Type: Journal Article
• Authors: Figueroa, Nicolás E; Hoffmann, Thomas; Olbricht, Klaus; Abrams, Suzanne R; Schwab, Wilfried
• Editors: Costa, Fabrizio
• Is Part Of: Journal of experimental botany. Volume 72:Number 4(2021)
• Page Start: 1245
• Page End: 1259
• Publication Date: 2020-11-01
• Subjects: ABA -- ABA-GE -- catabolism -- fruit ripening -- glucosyltransferase -- hydroxylase -- metabolism -- phaseic acid -- strawberry; Botany -- Periodicals; Botany, Experimental -- Periodicals; Plant physiology -- Periodicals; 580
• DOI: 10.1093/jxb/eraa503
• Languages: English
• ISSNs: 0022-0957

Abstract

Abstract : Concentrations of abscisic acid metabolites were significantly higher in the receptacle of Fragaria vesca fruit than in achenes and were considerably influenced by tissue, ripening stage, and strawberry genotype. Abstract: Abscisic acid (ABA) is a key hormone in non-climacteric Fragaria spp, regulating multiple physiological processes throughout fruit ripening. Its concentration increases during ripening, and it promotes fruit (receptacle) development. However, its metabolism in the fruit is largely unknown. We analyzed the concentrations of ABA and its catabolites at different developmental stages of strawberry ripening in diploid and octoploid genotypes and identified two functional ABA-glucosyltransferases (FvUGT71A49 and FvUGT73AC3) and two regiospecific ABA-8'-hydroxylases (FaCYP707A4a and FaCYP707A1/3). ABA-glucose ester content increased during ripening in diploid F . vesca varieties but decreased in octoploid F .× ananassa . Dihydrophaseic acid content increased throughout ripening in all analyzed receptacles, while 7'-hydroxy-ABA and neo-phaseic acid did not show significant changes during ripening. In the studied F . vesca varieties, the receptacle seems to be the main tissue for ABA metabolism, as the concentration of ABA and its metabolites in the receptacle was generally 100 times higher than in achenes. The accumulation patterns of ABA catabolites and transcriptomic data from the literature show that all strawberry fruits produce and metabolize considerable amounts of the plant hormone ABA during ripening, which is therefore a conserved process, but also illustrate the diversity of this metabolic pathway which is species, variety, and tissue dependent.