Title: “Milk of the Poppy: More Than Meets the Eye”
Host: Dr. Yanran Li
Abstract: Opium poppy remains to sole commercial source of many pharmaceutical alkaloids including morphine, codeine and derivatives of thebaine, such as oxycodone and naloxone. Natural opiate biosynthesis involves two cell types – sieve elements of the phloem and adjacent laticifers. The milky and alkaloid-rich laticifer cytoplasm is known as latex, which exudes upon lancing from unripe seed capsules, and yields raw opium after partial oxidation and drying. Once thought to serve only in the capacity of alkaloid storage, we have shown that opium poppy latex also directly participates in alkaloid biosynthesis with several enzymes occurring predominantly in laticifers. The participation of two cell types in the formation and accumulation of opiate alkaloids has implicated a web of additional cellular components and regulatory mechanisms that we are beginning to unravel. In my seminar, I will discuss alkaloid biosynthesis in opium poppy with a focus on the unique cell biology and metabolic role of laticifers.