Diabetes 52:425-433, 2003
© 2003 by the American Diabetes Association, Inc.
Pax-6 Activates Endogenous Proglucagon Gene Expression in the Rodent Gastrointestinal Epithelium
Denny K.Y. Trinh1,
Kai Zhang1,
Moazzem Hossain1,
Patricia L. Brubaker2, and
Daniel J. Drucker1
1 Department of Medicine, Banting and Best Diabetes Center, Toronto General Hospital, University of Toronto, Toronto, Ontario, Canada
2 Departments of Physiology and Medicine, University of Toronto, Toronto, Ontario, Canada
The proglucagon gene encodes pancreatic glucagon and the glucagon-like peptides, which exert diverse effects on nutrient absorption and assimilation. The therapeutic potential of glucagon-like peptide-1 (GLP-1) has fostered interest in development of cellular engineering approaches to augment endogenous intestinal-derived GLP-1 for the treatment of type 2 diabetes. We have used adenovirus technology to examine the potential roles of the transcription factors Cdx-2/3 and Pax-6 as activators of endogenous proglucagon gene expression in enteroendocrine cell lines and in nontransformed rat intestinal cells. Adenoviral-expressed Cdx-2/3 and Pax-6 activated proglucagon promoter-luciferase activity in baby hamster kidney (BHK) fibroblasts, HEK 293 cells, and enteroendocrine cell lines. Pax-6, but not Cdx-2/3, induced expression of the endogenous proglucagon gene in enteroendocrine cell lines, but not in heterologous fibroblasts. Furthermore, transduction of primary rat intestinal cell cultures in vitro, or the rat colonic epithelium in vivo, with Ad-Pax-6 activated endogenous proglucagon gene expression. These data demonstrate that Pax-6, but not Cdx-2/3, is capable of activating the endogenous proglucagon gene in both immortalized enteroendocrine cells and the nontransformed intestinal epithelium in vivo.

CiteULike Del.icio.us Digg Reddit Technorati What's this?
This article has been cited by other articles:

|
 |

|
 |
 
J. J. Holst
The Physiology of Glucagon-like Peptide 1
Physiol Rev,
October 1, 2007;
87(4):
1409 - 1439.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
J. Gromada, I. Franklin, and C. B. Wollheim
{alpha}-Cells of the Endocrine Pancreas: 35 Years of Research but the Enigma Remains
Endocr. Rev.,
February 1, 2007;
28(1):
84 - 116.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
F. Yi, P. L. Brubaker, and T. Jin
TCF-4 Mediates Cell Type-specific Regulation of Proglucagon Gene Expression by {beta}-Catenin and Glycogen Synthase Kinase-3{beta}
J. Biol. Chem.,
January 14, 2005;
280(2):
1457 - 1464.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
G. Flock, X. Cao, and D. J. Drucker
Pdx-1 Is Not Sufficient for Repression of Proglucagon Gene Transcription in Islet or Enteroendocrine Cells
Endocrinology,
January 1, 2005;
146(1):
441 - 449.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
S. E. Schonhoff, M. Giel-Moloney, and A. B. Leiter
Minireview: Development and Differentiation of Gut Endocrine Cells
Endocrinology,
June 1, 2004;
145(6):
2639 - 2644.
[Abstract]
[Full Text]
[PDF]
|
 |
|
Copyright © 2003 by the American Diabetes Association.
|
|
| |
|