The chimeric repressor version of an Ethylene Response Factor(ERF) family member, Sl-ERF.B3, shows contrasting effects on tomato fruit ripening

Mingchun Liu (1) , Gianfranco Diretto (2) , Julien Pirrello (1) , Jean-Paul Roustan (1) , Zhengguo Li (3) , Giovanni Giuliano (2) , Farid Regad (1) , Mondher Bouzayen (1)

1 GBF - Génomique et Biotechnologie des Fruits
2 ENEA - Italian National Agency for New Tecnologies Energy and Sustainable Economic Development
3 Chongqing University

Fruit ripening involves a complex interplay between ethylene and ripening-associated transcriptional regulators. Ethylene Response Factors (ERFs) are downstream components of ethylene signaling, known to regulate the expression of ethylene-responsive genes. Although fruit ripening is an ethylene-regulated process, the role of ERFs remains poorly understood. The role of Sl-ERF.B3 in tomato (Solanum lycopersicum) fruit maturation and ripening is addressed here using a chimeric dominant repressor version (ERF.B3-SRDX). Over-expression of ERF.B3-SRDX results in a dramatic delay of the onset of ripening, enhanced climacteric ethylene production and fruit softening, and reduced pigment accumulation. Consistently, genes involved in ethylene biosynthesis and in softening are up-regulated and those of carotenoid biosynthesis are down-regulated. Moreover, the expression of ripening regulators, such as RIN, NOR, CNR and HB-1, is stimulated in ERF.B3-SRDX dominant repressor fruits and the expression pattern of a number of ERFs is severely altered. The data suggest the existence of a complex network enabling interconnection between ERF genes which may account for the pleiotropic alterations in fruit maturation and² ripening. Overall, the study sheds new light on the role of Sl-ERF.B3 in the transcriptional network controlling the ripening process and uncovers a means towards uncoupling some of the main ripening-associated processes.

Mots clés: Solanum lycopersicum (tomato); Ethylene Response Factor (ERF); ethylene; dominant repressor; fruit ripening; Dominant repressor; Ethylene; Ethylene response factor(ERF)- Fruit ripening; Solanum lycopersicum (tomato)

Domaines: Génomique, Transcriptomique et Protéomique [q-bio.GN]; Biologie végétale

Mingchun Liu, Gianfranco Diretto, Julien Pirrello, Jean-Paul Roustan, Zhengguo Li, et al.. The chimeric repressor version of an Ethylene Response Factor(ERF) family member, Sl-ERF.B3, shows contrasting effects on tomato fruit ripening. New Phytologist, 2014, 203 (1), pp.206-218. ⟨10.1111/nph.12771⟩. ⟨hal-02632475⟩