J Biol Chem 2002 Feb 19;277(5):3680-5. Epub 2001 Nov 19.
Section on Islet Transplantation and Cell Biology and Section on Vascular Cell Biology, Joslin Diabetes Center, Boston, Massachusetts 02215, USA.
The expression of the basic helix-loop-helix transcription factor c-Myc is induced in pancreatic islets of several different diabetic model animals and is possibly involved in suppression of the insulin gene transcription. In this study, we found that activity of protein kinase C is increased by high glucose, preceding the induction of c-myc expression and that PKC beta2 specifically regulates c-myc expression in pancreatic beta-cells. Since PKC alpha, beta2, delta, epsilon, and zeta were expressed in rat pancreatic islets, we prepared each wild type (WT) and dominant negative type (DN) PKC isoform (alpha, beta2, delta, epsilon, and zeta)-expressing adenovirus to examine the effect of each PKC isoform on c-myc expression. Read More