Article

Characterization of the expression, localization, and secretion of PANDER in alpha-cells.

Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia Research Institute, Philadelphia, PA 19104-4318, USA.
Molecular and Cellular Endocrinology (Impact Factor: 4.24). 08/2010; 325(1-2):36-45. DOI: 10.1016/j.mce.2010.05.008
Source: PubMed

ABSTRACT The novel islet-specific protein PANcreatic DERived Factor (PANDER; FAM3B) has been extensively characterized with respect to the beta-cell, and these studies suggest a potential function for PANDER in the regulation of glucose homeostasis. Little is known regarding PANDER in pancreatic -cells, which are critically involved in maintaining euglycemia. Here we present the first report elucidating the expression and regulation of PANDER within the alpha-cell. Pander mRNA and protein are detected in alpha-cells, with primary localization to a glucagon-negative granular cytosolic compartment. PANDER secretion from alpha-cells is nutritionally and hormonally regulated by l-arginine and insulin, demonstrating similarities and differences with glucagon. Signaling via the insulin receptor (IR) through the PI3K and Akt/PKB node is required for insulin-stimulated PANDER release. The separate localization of PANDER and glucagon is consistent with their differential regulation, and the effect of insulin suggests a paracrine/endocrine effect on PANDER release. This provides further insight into the potential glucose-regulatory role of PANDER.

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