Genome assembly provided new insights into the Cinnamomum burmannii evolution and D-borneol biosynthesis differences between chemotypes

Authors：Li, Fangping; Huang, Shilin; Mei, Yu; Wu, Bingqi; Hou, Zhuangwei; Zhan, Penglin; Hou, Zhihao; Huang, Wenjie; Zhao, Junliang^*; Wang, Jihua^*

Source：INDUSTRIAL CROPS AND PRODUCTS, 2022, 186: 115181.

DOI：10.1016/j.indcrop.2022.115181

• Cinnamomum species
• Cinnamomum burmannii
• Genome
• D-borneol
• Chemotypes

D-Borneol is a precious monoterpenoid widely used in the pharmaceutical and cosmetic industries. Cinnamomum burmannii (Nees et T.Nees) Blume (C. burmannii) is one of the key resources for D-Borneol. However, only one chemotype of C. burmannii contain high content of D-Borneol in its leaves and stems. Limited by little information from C. burmannii, the D-Borneol biosynthesis mechanisms, as well as the mechanisms underlying the D-Borneol production differences among chemotypes remains elusive. To fill these gaps, we generated a completed genome of a high D-Borneol content chemotype of C. burmannii. Phylogenetic analysis suggests that C. burmannii is sister to a clade containing C. camphora and C. kanehirae while the variations of chromosome structure and LTR-RTs are important factors for differentiation in Cinnamomum. Further comparison of genome sequence demon-strated few genomic sequence differences between two chemotypes of C. burmannii. However, the pathway and transcriptomic profiling analysis revealed the expression differences of the genes in MEP pathway, a main pathway responsible for D-Borneol synthesis, which may be the critical determinant for the D-Borneol production differences between the two chemotypes. Our results also implied epigenetic modulation may participate in this process. Finally, a genome database (CAMD) of Cinnamomum species was constructed for better resources exploration. The present study provided the first high-quality genome and comprehensive genomic resources of C. burmannii. which not only provided new insights into the evolution of Cinnamomum species, but also shed light on the mechanisms of D-Borneol biosynthesis and the molecular signatures characterized high and low D-Borneol chemotypes of C. burmannii.

• Institution
  广东省农业科学院; 华南农业大学