| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Submitted on April 2, 2003
Accepted on December 23, 2003
Gene Expression in an Activin-Dependent Manner in Immortalized Gonadotropes
1 Departments of Reproductive Medicine and Neurosciences, Center for the Study of Reproductive Biology and Disease, University of California, San Diego, La Jolla, California 92093-0674
* To whom correspondence should be addressed. E-mail: pmellon{at}ucsd.edu.
Little is known about the molecular mechanisms of androgen regulation of the FSH
gene; however, studies suggest that it consists of a complex feedback loop that involves multiple mechanisms acting at both the level of the hypothalamus and the pituitary. In the present study, we address androgen regulation of the FSH gene in immortalized gonadotrope cells and investigate the roles of activin and GnRH (GnRH) in androgen action. Using transient transfection assays in the FSH-expressing mouse gonadotrope cell line, LT2, we demonstrate that androgens stimulate expression of an ovine FSH reporter gene in a dose-dependent manner. Mutation of either of two conserved androgen response elements at -245/-231 and -153/-139 within the proximal region of the ovine FSH gene promoter abolishes this stimulation and androgen receptor binds directly to the -244 ARE in vitro. Androgen induction of the FSH reporter gene is also dependent upon the activin autocrine loop present in the LT2 cells, as well as an activin-response element at -138/-124 of the FSH gene. However, activin regulation of other genes remains unaffected by androgens. In addition, androgens stimulate expression of a mouse GnRH receptor reporter gene, and thus may indirectly augment the response of the FSH gene to GnRH. Taken together, these data demonstrate that, in mouse gonadotropes, androgens act directly on the ovine FSH gene to stimulate expression by a mechanism that is dependent upon activin, as well as acting indirectly, potentially through a second mechanism that may be dependent upon induction of GnRH receptor.
NURSA Molecule Pages Link:
This article has been cited by other articles:
 |
|
 |
|
  V. G. Thackray and P. L. Mellon Synergistic Induction of Follicle-Stimulating Hormone {beta}-Subunit Gene Expression by Gonadal Steroid Hormone Receptors and Smad Proteins Endocrinology, March 1, 2008; 149(3): 1091 - 1102. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. L. Burger, D. J. Haisenleder, G. M. Wotton, K. W. Aylor, A. C. Dalkin, and J. C. Marshall The regulation of FSHbeta transcription by gonadal steroids: testosterone and estradiol modulation of the activin intracellular signaling pathway Am J Physiol Endocrinol Metab, July 1, 2007; 293(1): E277 - E285. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. M. McGillivray, V. G. Thackray, D. Coss, and P. L. Mellon Activin and Glucocorticoids Synergistically Activate Follicle-Stimulating Hormone {beta}-Subunit Gene Expression in the Immortalized L{beta}T2 Gonadotrope Cell Line Endocrinology, February 1, 2007; 148(2): 762 - 773. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 V. G. Thackray, S. M. McGillivray, and P. L. Mellon Androgens, Progestins, and Glucocorticoids Induce Follicle-Stimulating Hormone {beta}-Subunit Gene Expression at the Level of the Gonadotrope Mol. Endocrinol., September 1, 2006; 20(9): 2062 - 2079. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 D N R Veeramachaneni, J S Palmer, R P Amann, C M Kane, T T Higuchi, and K-Y F Pau Disruption of sexual function, FSH secretion, and spermiogenesis in rabbits following developmental exposure to vinclozolin, a fungicide. Reproduction, April 1, 2006; 131(4): 805 - 816. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W. H Walker and J. Cheng FSH and testosterone signaling in Sertoli cells Reproduction, July 1, 2005; 130(1): 15 - 28. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L L Burger, D J Haisenleder, A C Dalkin, and J C Marshall Regulation of gonadotropin subunit gene transcription J. Mol. Endocrinol., December 1, 2004; 33(3): 559 - 584. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. J Winters and J. P Moore Intra-pituitary regulation of gonadotrophs in male rodents and primates Reproduction, July 1, 2004; 128(1): 13 - 23. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| Endocrinology | Endocrine Reviews | J. Clin. End. & Metab. |
| Molecular Endocrinology | Recent Prog. Horm. Res. | All Endocrine Journals |
