|
|
||||||||
Department of Molecular Physiology and Biophysics, Vanderbilt University Medical School, Nashville, Tennessee 37232
Submitted 9 October 2003 ; accepted in final form 6 January 2004
We recently compared the regulation of glucose-6-phosphatase (G-6-Pase) catalytic subunit and glucose 6-phosphate (G-6-P) transporter gene expression by insulin in conscious dogs in vivo (Hornbuckle LA, Edgerton DS, Ayala JE, Svitek CA, Neal DW, Cardin S, Cherrington AD, and O'Brien RM. Am J Physiol Endocrinol Metab 281: E713E725, 2001). In pancreatic-clamped, euglycemic conscious dogs, a 5-h period of hypoinsulinemia led to a marked increase in hepatic G-6-Pase catalytic subunit mRNA; however, G-6-P transporter mRNA was unchanged. Here, we demonstrate, again using pancreatic-clamped, conscious dogs, that glucagon is a candidate for the factor responsible for this selective induction. Thus glucagon stimulated G-6-Pase catalytic subunit but not G-6-P transporter gene expression in vivo. Furthermore, cAMP stimulated endogenous G-6-Pase catalytic subunit gene expression in HepG2 cells but had no effect on G-6-P transporter gene expression. The cAMP response element (CRE) that mediates this induction was identified through transient transfection of HepG2 cells with G-6-Pase catalytic subunit-chloramphenicol acetyltransferase fusion genes. Gel retardation assays demonstrate that this CRE binds several transcription factors including CRE-binding protein and CCAAT enhancer-binding protein.
insulin; fatty acids; gene transcription; cyclic adenosine monophosphate; glucose-6-phosphatase; glucose 6-phosphate
This article has been cited by other articles:
![]() |
C. Xu, K. Chakravarty, X. Kong, T. T. Tuy, I. J. Arinze, F. Bone, and D. Massillon Several Transcription Factors Are Recruited to the Glucose-6-Phosphatase Gene Promoter in Response to Palmitate in Rat Hepatocytes and H4IIE Cells J. Nutr., March 1, 2007; 137(3): 554 - 559. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Everett-Grueter, D. S. Edgerton, E. P. Donahue, S. Vaughan, C. A. Chu, D. K. Sindelar, and A. D. Cherrington The effect of an acute elevation of NEFA concentrations on glucagon-stimulated hepatic glucose output Am J Physiol Endocrinol Metab, September 1, 2006; 291(3): E449 - E459. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. Desvergne, L. Michalik, and W. Wahli Transcriptional Regulation of Metabolism Physiol Rev, April 1, 2006; 86(2): 465 - 514. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |