Transcriptomic analysis of Toona sinensis leaves with eight different colors at various developmental stages

Toona sinensis, a medicinal and edible plant, holds economic and ecological significance in Asia. Despite its diverse applications, the genetic basis of leaf color formation remains unclear. This study aimed to investigate the molecular mechanisms underlying color variations across three cultivars (red, brown, green) at different developmental stages. Young tender leaflets from apical tips and fully expanded leaflets from basal positions of the same compound leaf were collected for RNA-Seq analysis. Differential expression analysis revealed significant enrichment of genes involved in flavonoid biosynthesis, phenylpropanoid biosynthesis, and carotenoid metabolism pathways, suggesting their key roles in pigment accumulation. These metabolites are not only critical for coloration but also contribute to disease resistance and antioxidation. This research provides novel insights into the genetic regulatory networks governing leaf color formation in T. sinensis, facilitating molecular breeding for color trait improvement.