Manipulation of β-carotene levels in tomato fruits results in increased ABA content and extended shelf-life

Authors

Gianfranco Diretto, Casaccia Research CenterFollow
Sarah Frusciante, Casaccia Research Center
Claudia Fabbri, Sapienza University of Rome
Nicolas Schauer, Max-Planck-Institute
Lucas Busta, University of Nebraska - LincolnFollow
Zhonghua Wang, University of British Columbia
Antonio J. Matas, Cornell University
Alessia Fiore, Casaccia Research Center
Jocelyn K. C. Rose, Cornell University
Alisdair R. Fernie, Max-Planck-Institute
Reinhard Jetter, University of British ColumbiaFollow
Benedetta Mattei, Sapienza University of Rome
Jim Giovannoni, USDA, Agricultural Research Service
Giovanni Giuliano, Casaccia Research CenterFollow

ORCID IDs

Jocelyn K. C. Rose

Giovanni Giuliano

Document Type

Article

Date of this Version

2019

Citation

Plant Biotechnol J. 2019 Oct 24.

Comments

Open access

doi: 10.1111/pbi.13283

Abstract

Tomato fruit ripening is controlled by the hormone ethylene and by a group of transcription factors, acting upstream of ethylene. During ripening, the linear carotene lycopene accumulates at the expense of cyclic carotenoids. Fruit-specific overexpression of LYCOPENE β-CYCLASE (LCYb) resulted in increased β-carotene (provitamin A) content. Unexpectedly, LCYb-overexpressing fruits also exhibited a diverse array of ripening phenotypes, including delayed softening and extended shelf life. These phenotypes were accompanied, at the biochemical level, by an increase of abscisic acid (ABA) content, decreased ethylene production, increased density of cell wall material containing linear pectins with a low degree of methylation, and a thicker cuticle with a higher content of cutin monomers and triterpenoids. The levels of several primary metabolites and phenylpropanoid compounds were also altered in the transgenic fruits, which could be attributed to delayed fruit ripening and/or to ABA. Network correlation analysis and pharmacological experiments with the ABA biosynthesis inhibitor, abamine, indicated that altered ABA levels were a direct effect of the increased β-carotene content and were in turn responsible for the extended shelf life phenotype. Thus, manipulation of -carotene levels results not only in an improvement of the nutritional value of tomato fruits, but also of their shelf life.