Transcriptome Analysis Reveals Key Genes and Pathways in Borneol Biosynthesis of a New Borneol-Chemotype Cinnamomum camphora

Abstract

Natural borneol, a valuable monoterpenoid, is primarily derived from Cinnamomum camphora chvar. borneol. This unique Chinese tree was studied using the high-borneol cultivar ‘Ganlong 2’ and common camphor trees as material. Multi-location trials over three years confirmed that ‘Ganlong 2’ stably exhibits high borneol content, high essential oil yield, and low camphor content, presenting an ideal system for biosynthesis research. Transcriptomic analysis identified key differentially expressed genes (DEGs), and KEGG enrichment outlined the (+)-borneol biosynthesis pathway. Critical genes, including CcBPPS, CcNUDX1, and CcDXS1, were highlighted, with the MEP pathway confirmed as the primary biosynthetic route. These findings advance the understanding of monoterpenoid biosynthesis regulation and provide a theoretical and genetic basis for improving natural borneol production via synthetic biology and breeding high-quality varieties.