transcriptome analysis of needles of var. .

Podophyllotoxin is a starting material of the semisynthetic anticancer medicines etoposide, teniposide, and etopophos. The major plant source of podophyllotoxin is rhizomes of , which is a Himalayan endangered species; therefore, alternative sources of podophyllotoxin or bioproduction systems have been pursued to avoid exploiting this limited natural resource. In this paper, we report de novo transcriptome analysis of var. , which accumulates the podophyllotoxin derivatives (deoxypodophyllotoxin and β-peltatin A methyl ether) in its needles. We analyzed transcriptomes of the var. young needles to obtain the sequences that putatively encode -methyltransferases, cytochrome P450s, and a 2-oxoglutarate dependent dioxygenase because these protein families are responsible for podophyllotoxin-related compound formation in . The resulting transcriptomes contained considerable numbers of coding sequences classified into the three protein families. Our results are a genetic basis for identifying genes involved in the biosynthesis of podophyllotoxin and related compounds and also for future metabolic engineering of podophyllotoxin in heterologous hosts.