Up-regulation of rat uroguanylin mrna by dietary zinc restriction. Blanchard, Raymond K., and Robert J. Cousins. Food Science and Human Nutrition Department, Center for Nutritional Sciences, University of Florida ,Gainesville, Florida 32611
APStracts 3:0268G, 1996.
A cDNA for the rat uroguanylin precursor was identified as up -regulated in zinc deficient rats by differential display of intestinal mRNA and subsequently cloned. The cDNA and deduced amino acid sequences show a high degree of homology to human and opossum preprouroguanylin sequences. When used as a probe for northern blot analysis of RNA from rat intestinal mucosa, the uroguanylin cDNA hybridized to a single species of mRNA that was 2.5-fold more abundant in zinc deficiency. A tissue distribution survey indicates that while the small intestine expresses a disproportionately high level of preprouroguanylin, this hormone precursor is also expressed in the colon, stomach, kidney, thymus, and testis. The induction by zinc deficiency is the first reported case of gene regulation for this hormone. These results also support a potential mechanism to explain, at least in part, the beneficial effects of zinc supplementation for secretory diarrhea prevalent in many areas of the world.

Received 14 June 1996; accepted in final form 9 December 1996.
APS Manuscript Number G241-6.
Article publication pending Am. J. Physiol. (Gastrointest. Liver
Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 31 December 1996