# Molecular Interaction of Genes Related to Anthocyanin, Lipid and Wax Biosynthesis in Apple Red-Fleshed Fruits

## TL;DR

This study explores how genes related to anthocyanin, lipid, and wax biosynthesis interact in red-fleshed apples, revealing molecular connections that affect fruit properties.

## Contribution

The paper identifies specific gene interactions linking anthocyanin content to lipid and wax metabolism in apple fruits.

## Key findings

- Red-fleshed apples show higher activity of AlcFARed, CER1, PalmTransf, and CYP86A4 genes.
- Anthocyanin enrichment correlates with reduced wax coating in apple flesh.
- TropRed inhibition and activation of Cyp865B1 and CYP86A4 suggest roles in wax formation via primary alcohols and alkanes.

## Abstract

Transcriptomic analysis of fruit flesh of the cultivars ‘Trinity’ (red-fleshed) and ‘Free Redstar’ (white-fleshed) uncovered a set of ten genes involved in different metabolic pathways. Three—N3Dioxy, LAR1 and F3Mo—were mapped via phenylpropanoid and flavonoid biosynthesis (mdm00940, mdm00941); four—AlcFARed, CER1, Cyp86A4 and PalmTransf—were mapped on the cutin, suberine and wax biosynthesis pathways (mdm00073); and three—TropRed, CyP865B1 and CytP450—were mapped via the tropane/piperidine/pyridine alkaloid biosynthesis pathway and the peroxisome pathway (KEGG:mdm00960, KEGG:mdm04146). Our study highlighted the higher activity of AlcFARed, CER1, PalmTransf and CYP86A4 in red-fleshed apple fruits and allowed us to discover a specific relationship between significant reductions in fruit wax coating and anthocyanin enrichment in fruit flesh. In addition, the uncovered inhibition of the TropRed gene and the activation of both Cyp865B1 and CYP86A4 suggests that both compounds generate primary alcohols and alkanes, ultimately bound to wax formation. Our results postulate that the fatty acid degradation process is initiated in the flesh of apple fruits and depends on the relationship between anthocyanin content and lipid and wax metabolism. These findings further our understanding of the molecular mechanism linking anthocyanin and wax, making it significantly important in the context of apple fruit storage stability.