|
|
||||||||
1 Department of Nutrition, University of Tennessee, Knoxville, Tennessee 37996
2 Zen-Bio Inc., Research Triangle Park, North Carolina 27709
3 Division of Plastic Surgery, University of Tennessee Medical Center at Knoxville, Knoxville, Tennessee 37920
Claycombe, Kate J., Yanxin Wang, Brynn H. Jones, Suyeon Kim, William O. Wilkison, Michael B. Zemel, Joseph Chun, and Naima Moustaid-Moussa. Transcriptional regulation of the adipocyte fatty acid synthase gene by agouti: interaction with insulin. Physiol Genomics 3: 157162, 2000.Mice carrying dominant mutations at the agouti locus exhibit ectopic expression of agouti gene transcripts, obesity, and type II diabetes through unknown mechanisms. To gain insight into the role of agouti protein in modulating adiposity, we investigated regulation of a key lipogenic gene, fatty acid synthase (FAS) by agouti alone and in combination with insulin. Both agouti and insulin increase FAS activity in 3T3-L1 and in human adipocytes. Agouti and insulin independently and additively increase FAS activity in 3T3-L1 adipocytes. We further investigated the mechanism responsible for the agouti-induced FAS expression in these cells and demonstrated that both insulin (3-fold increase) and agouti (2-fold) increased FAS gene expression at the transcriptional level. Furthermore, insulin and agouti together exerted additive effects (5-fold increase) on FAS gene transcription. Transfection assays of FAS promoter-luciferase fusion gene constructs into 3T3-L1 adipocytes indicated that the agouti response element(s) is (are) located in the -435 to -415 region (-435/-415) of the FAS promoter. Nuclear proteins binding to this novel sequence are adipocyte specific. Thus the agouti response sequences mapped to a region upstream of the insulin-responsive element (which we previously reported to be located at -67/-52), consistent with additive effects of these two factors on FAS gene transcription.
gene transcription; regulatory sequences
This article has been cited by other articles:
![]() |
J. C. Hogan and J. M. Stephens The Regulation of Fatty Acid Synthase by STAT5A Diabetes, July 1, 2005; 54(7): 1968 - 1975. [Abstract] [Full Text] [PDF] |
||||
![]() |
X. Sun and M. B. Zemel Calcium and Dairy Products Inhibit Weight and Fat Regain during Ad Libitum Consumption Following Energy Restriction in Ap2-Agouti Transgenic Mice J. Nutr., November 1, 2004; 134(11): 3054 - 3060. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. B Zemel Role of calcium and dairy products in energy partitioning and weight management Am. J. Clinical Nutrition, May 1, 2004; 79(5): 907S - 912S. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Wang, B. Jones Voy, S. Urs, S. Kim, M. Soltani-Bejnood, N. Quigley, Y.-R. Heo, M. Standridge, B. Andersen, M. Dhar, et al. The Human Fatty Acid Synthase Gene and De Novo Lipogenesis Are Coordinately Regulated in Human Adipose Tissue J. Nutr., May 1, 2004; 134(5): 1032 - 1038. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. B. Zemel Mechanisms of Dairy Modulation of Adiposity J. Nutr., January 1, 2003; 133(1): 252S - 256. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |