- Friday, November 20, 2015
- 1:30 PM–2:30 PM
- Science Building 010
Vonny Salim, Ph.D Michigan State University
Madagascar periwinkle (Catharanthus roseus) and Chinese Happy Tree (Camptotheca acuminata) are the source of the important anticancer drugs, monoterpene indole alkaloids (MIA) that have been extensively used for chemotherapy treatment of various types of cancer. These medicinal plants accumulate a number of MIAs that originate from the coupling of tryptamine and secologanin by strictosidine synthase to form strictosidine from which all other MIAs are generated, including vinblastine, vincristine, and camptothecin. Although some strategies have been developed for metabolic engineering efforts to produce these valuable MIAs, unidentified biosynthetic genes in the pathway limit this potential. The transcriptomic data of several MIA-accumulating plants is facilitating the identification of MIA candidate genes. I will discuss how virus-induced gene silencing (VIGS) is being used to screen candidate genes for their involvement in MIA biosynthesis, such as in the functional characterization of two cytochrome P450 genes in secologanin biosynthesis pathway of C. roseus. The identification of these two genes has allowed the reconstitution of the entire secologanin pathway in heterologous hosts, such as yeast for rapid and inexpensive production of strictosidine.
