Posted by Dennis on May 29, 2002 at 17:06:23:
I think James submitted preliminary work by this group a year ago.
NGN3 EXPRESSION LEADS TO FUNCTIONAL PANCREATIC DEVELOPMENT IN ANIMAL MODE
WESTPORT, CT (Reuters Health) Feb 26 - Ectopic expression of the pancreatic regulatory gene NGN3 turns endodermal cells of any region into islet-forming endocrine cells that secrete glucagon and somatostatin, according to animal study results published in the February 15th issue of Genes and Development.
The investigators infer that it might be possible to introduce simple gene combinations into therapeutic stem cells in order to achieve endodermal tissue differentiation.
Dr. Anne Grapin-Botton and colleagues, from Harvard University, Cambridge, Massachusetts, used a novel gene analysis method to study the role that various regulatory genes play in pancreatic development. The new technique, which yields results in only about 15 days, involves introducing one or more genes of interest into the endoderm of live chick embryos.
"The Pdx-1 gene that we studied is often thought of as a master gene, a gene capable of generating a whole organ," Dr. Grapin-Botton told Reuters Health. "We found that Pdx-1 does not produce complete pancreatic cell differentiation, but it does seem to play an important role in the initial formation of the gland," she noted. "In terms of treating diabetes, Pdx-1 is clearly not the solution."
"We were most successful when we used the NGN3 gene," Dr. Grapin-Botton continued. "Expression of NGN3 led to the differentiation of not only glucagon-producing cells, but also somatostatin-producing cells." In addition, "these cells also formed islets," she added.
Dr. Grapin-Botton's team is currently searching for one or more genes that will lead to the development of insulin-producing cells.
Genes Dev 2001;15:00-00