The NAC side of the fruit: tuning of fruit development and maturation

Abstract

Fruits and seeds resulting from fertilization of flowers, represent an incredible evolutionary advantage in angiosperms and have seen them become a critical element in our food supply.Many studies have been conducted to reveal how fruit matures while protecting growing seeds and ensuring their dispersal. As result, several transcription factors involved in fruit maturation and senescence have been isolated both in model and crop plants. These regulators modulate several cellular processes that occur during fruit ripening such as chlorophyll breakdown, tissue softening, carbohydrates and pigments accumulation.The NAC superfamily of transcription factors is known to be involved in almost all these aspects of fruit development and maturation. In this review, we summarise the current knowledge regarding NACs that modulate fruit ripening in model species (Arabidopsis thaliana and Solanum lycopersicum) and in crops of commercial interest (Oryza sativa, Malus domestica, Fragaria genus, Citrus sinensis and Musa acuminata).

Keywords: Fruit; NAC; Ripening; Senescence; Transcription factor.

Fig. 1

NACs play a role in numerous processes during a plant’s lifecycle, summarized in the figure using Solanum lycopersicum as representative plant. Each box represents a process, significant examples of NAC TFs involved are reported as references between brackets

Fig. 2

Structural domains and subdomains of NAC TFs

Fig. 3

Overview of the principle fruit-related processes which NAC transcription factors are involved in. Each colour represents a specific aspect of fruit ripening, and the NAC genes listed in this review are located accordingly