TIGHT HORMONAL-CONTROL OF PRP GENE-EXPRESSION IN ENDOCRINE PANCREATIC-CELLS

In this work, we have studied whether PrP, a protein found predominant ly on the surface of neurons, could also exist in pancreatic endocrine cells. For this purpose, we have compared the expression of PrP mRNAs in insulin- (beta) and glucacon- (alpha) producing cells to that of n euronal and nonneuronal cells. We show that PrP mRNAs are expressed in all the beta and alpha cells tested at levels similar to those observ ed in neuronal cells. We also show that the expression of PrP is tight ly regulated by hormones. Indeed, recombinant human growth hormone and dexamethasone, 2 factors implicated in beta cell maturation, increase PrP mRNA steady state level. PrP can thus be added to the list of neu ronal factors expressed in the endocrine pancreas. Moreover, beta cell s could represent a new model to study the control of PrP expression. (C) 1994 Academic Press, Inc.