Transcription factor expression during pancreatic islet regeneration

Abstract

Recent studies by a number of laboratories have identified transcription factors that are involved in pancreatic development. Indeed, marked abnormalities in pancreatic development result from deficiencies in these molecules, which include, among others, PDX-1, islet-1 (Isl-1), and Pax-6. These studies have prompted us to evaluate the expression of Isl-1 and Pax-6 in the pancreas of the interferon-gamma (IFNγ) transgenic mouse, which exhibits new islet growth and expansion of ducts throughout the life of the animal. We have previously demonstrated that PDX-1 is strikingly expressed in the ducts of the IFNγ transgenic mouse. This latter observation compelled us to examine expression of hepatocyte nuclear factor-3beta (HNF3β), which mediates PDX-1 gene transcription, in the IFNγ transgenic pancreas as well. As a result of these studies, we now demonstrate marked expression of these transcription factors in the pancreatic ducts of IFNγ transgenic mice. These data suggest a role for these transcription factors during pancreatic regeneration in the IFNγ transgenic mouse.