| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
Department of Animal Sciences (D.G., T.E., R.M.R.), University of Missouri, Columbia, Missouri 65211; and Department of Molecular Genetics (M.C.O.), Ohio State University, Columbus, Ohio 43210
Address all correspondence and requests for reprints to: R. Michael Roberts, 158 Animal Science Research Center, University of Missouri-Columbia 920 East Campus Drive, Columbia, Missouri 65211-5300. E-mail: RobertsRM{at}missouri.edu.
Ets-2 has an important role in controlling the differentiation of the placenta. Here we show by truncation and mutational analysis that two closely spaced Ets-2 binding sites in the proximal promoter of the human chorionic gonadotropin ß5 (hCGß5) gene constitute a major enhancer for hCGß gene expression in JAr and JEG-3 human choriocarcinoma cells and in mouse NIH3T3 cells. Contrary to a previous report, we also demonstrate that the ability of Ets-2 to enhance transcription is subject to control by the Ras/MAPK pathway, although this relationship is less easily demonstrable in JAr and JEG-3 choriocarcinoma cells than in the 3T3 cells because the former already possess a fully activated MAPK pathway and contain Ets-2 phosphorylated at threonine residue at T72. Coexpression of Ets-2 and activated Ras in 3T3 cells led to activation of MAPK/ERK kinase 1/2, phosphorylation of Ets-2 at T72, and an approximately 120-fold up-regulation of reporter gene expression from a short (-175) hCGß promoter. Fold activation in JAr and JEG-3 cells was rather less (20- to 30-fold), but basal activity was much higher. These effects on promoter activity were largely reversed in presence of the MAPK inhibitor PD98059, which prevents ERK1/2 activation, and partially reversed by mutating T72 on Ets-2. We finally show that the ability of 8-bromoadenosine-cAMP to stimulate hCGß promoter activity in JAr and JEG-3 cells occurs with a short promoter lacking the upstream elements previously considered to be essential for cAMP activation of the gene and, through mutational analysis, confirm that the major cAMP effects on the hCGß promoter are mediated through the proximal Ets-2 enhancer. The data are consistent with the hypothesis that Ets-2 has a general and possibly essential role in controlling the activity of genes associated with trophectoderm differentiation.
This article has been cited by other articles:
![]() |
T. Ezashi, P. Das, R. Gupta, A. Walker, and R. M. Roberts The Role of Homeobox Protein Distal-Less 3 and Its Interaction with ETS2 in Regulating Bovine Interferon-Tau Gene Expression-Synergistic Transcriptional Activation with ETS2 Biol Reprod, July 1, 2008; 79(1): 115 - 124. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. Das, T. Ezashi, R. Gupta, and R. M. Roberts Combinatorial Roles of Protein Kinase A, Ets2, and 3',5'-Cyclic-Adenosine Monophosphate Response Element-Binding Protein-Binding Protein/p300 in the Transcriptional Control of Interferon-{tau} Expression in a Trophoblast Cell Line Mol. Endocrinol., February 1, 2008; 22(2): 331 - 343. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Rull, P. Hallast, L. Uuskula, J. Jackson, M. Punab, A. Salumets, R.K. Campbell, and M. Laan Fine-scale quantification of HCG beta gene transcription in human trophoblastic and non-malignant non-trophoblastic tissues Mol. Hum. Reprod., January 1, 2008; 14(1): 23 - 31. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Ghosh, S. Sachdev, M. Hannink, and R. M. Roberts Coordinate Regulation of Basal and Cyclic 5'-Adenosine Monophosphate (cAMP)-Activated Expression of Human Chorionic Gonadotropin-{alpha} by Ets-2 and cAMP-Responsive Element Binding Protein Mol. Endocrinol., April 1, 2005; 19(4): 1049 - 1066. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Ezashi and R. M. Roberts Regulation of Interferon-{tau} (IFN-{tau}) Gene Promoters by Growth Factors that Target the Ets-2 Composite Enhancer: A Possible Model for Maternal Control of IFN-{tau} Production by the Conceptus during Early Pregnancy Endocrinology, October 1, 2004; 145(10): 4452 - 4460. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. Petrovic, S. V. Bhagwat, W. J. Ratzan, M. C. Ostrowski, and L. H. Shapiro CD13/APN Transcription Is Induced by RAS/MAPK-mediated Phosphorylation of Ets-2 in Activated Endothelial Cells J. Biol. Chem., December 5, 2003; 278(49): 49358 - 49368. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Endocrinology | Endocrine Reviews | J. Clin. End. & Metab. |
| Molecular Endocrinology | Recent Prog. Horm. Res. | All Endocrine Journals |