Plants are a valuable source of alkaloids, a class of nitrogen-containing compounds that includes many important drugs. For instance, the Madagascar periwinkle (Catharanthus roseus) plant produces two anti-cancer compounds, vincristine and vinblastine, in addition to anti-hypertensive and sedative compounds, ajmalicine and serpentine, respectively. Since yields from whole plants are low and change with the growth conditions, we are investigating the application of plant cell cultures for producing these pharmaceuticals. Alkaloid production is transcriptionally regulated through the expression of genes that code for enzymes involved in the alkaloid biosynthetic pathway. However, the regulation of these genes is not well understood. Our research focuses on how the cells transcriptionally regulate the biosynthesis of these valuable compounds, especially when treated with jasmonate (a plant hormone), and on developing transgenic lines of the Madagascar perinwinkle that improve production of these alkaloids.