Huperzia serrata (H. serrata), a representative member of the Lycopodiaceae family, is an economically important traditional Chinese herb with the notably medicinal value. Among its divergent effectively bioactive lycopodium alkaloids, the huperzine A (HupA) is a promising drug for Alzheimer’s disease in China. However, the public genomics and transcriptomics resources of this plant are very limited, and the biosynthesis of HupA is still largely unknown.

Scientists from Prof. XIAO Youli’s group at Institute of Plant Physiology and Ecology of Chinese Academy of Sciences evaluated critical genes involving the biosynthetic pathway of huperzine A by phylogenetic analysis and tissue-specific gene expression clustering analysis. The study was published online in BMC Genomics.

In their study, L-lysine decarboxylase (LDC), copper amine oxidase (CAO) and polyketide synthase (PKS), 457 cytochrome P450 genes in H. serrata were discovered by tissue-specific gene expression in addition to three types of biochemically identified genes.

Also, 23 CYP450s involved in berberine bridge enzyme (BBE) class and secologanin synthase (SLS) class are evaluated as candidate genes for the formation and modification of the lycopodium alkaloids scaffold in biosynthesis of HupA. 

This study is the first report of global transcriptome analysis on all tissues of H. serrata, and critical genes involved in the biosynthesis of precursors and scaffold modifications of HupA are discovered and predicted. Using Illumina Highseq 4000 platform, a substantial RNA sequencing dataset from four different tissues (root, stem, leaf, and sporangia) in H. serrata is generated with 181,141 assembled unigenes.

The transcriptome data from this work not only provide an important resource for further investigating on metabolic pathways in H. serrata, but also shed light on synthetic biology study of HupA. 

The work was financially supported by the Science and Technology Commission of Shanghai Municipality, National Natural Science Foundation of China, etc.