Gene-specific silencing of SlPL16, a pectate lyase coding gene, extends the shelf life of tomato fruit

Pectate lyase plays an important role in fruit development and ripening. Although earlier studies showed SlPL, a pectate lyase encoding gene, functions dominantly in tomato fruit softening, the functions of many other pectate lyase encoding genes involved in tomato fruit development and softening remain unknown. Here, gene-specific silencing of SlPL16 (Solyc06g083580) by RNA interference (RNAi) resulted in reduced pectate lyase enzyme activity, pericarp thickness, and soluble sugar content, and increased both the firmness and shelf life of tomato fruit. Through microscopic observation, it was found that the SlPL16-RNAi pericarp had reduced cell size, in comparison to the wild-type (WT). Moreover, gene silencing of SlPL16 resulted in the down-regulation of genes involved in cell wall degradation and pectin synthesis at various fruit developmental stages. Together, these results indicate that SlPL16 provides an important supplement of pectate lyase activity in tomato fruit softening, along with a fundamental role in cell expansion during early fruit development. Additionally, this study provides a potential gene locus in genetic engineering to improve fruit storage tolerance.

Automated summary

This study discovered that the Silyc06g083580 gene plays an important role in tomato fruit development and softening. Gene-specific silencing of SlPL16 resulted in reduced pectate lyase enzyme activity, thicker pericarp, and lower soluble sugar content, while increasing fruit firmness and shelf life. Furthermore, the silencing of this gene led to a decrease in cell size and down-regulation of genes involved in cell wall degradation and pectin synthesis. Overall, this study highlights the significance of SlPL16 in tomato fruit softening and provides a potential target for genetic engineering to improve fruit storage tolerance.