NEW YORK (Reuters Health) - U.S. researchers have successfully expressed the precursor protein of insulin in lettuce and tobacco plants. Moreover, feeding these genetically modified plants to mice that have a tendency to become diabetic protected the animals against inflammation of the pancreas.Generating the proinsulin protein in plants is a low-cost alternative to standard production methods, Dr. Henry Daniell, from the University of Central Florida in Orlando, and colleagues note in their report in the Plant Biotechnology Journal.