Please use this identifier to cite or link to this item:
|dc.title||Gonadotropin-releasing hormone activation of C-jun, but not early growth response factor-1, stimulates transcription of a luteinizing hormone β-subunit gene|
|dc.identifier.citation||Melamed, P., Zhu, Y., Siew, H.T., Xie, M., Koh, M. (2006). Gonadotropin-releasing hormone activation of C-jun, but not early growth response factor-1, stimulates transcription of a luteinizing hormone β-subunit gene. Endocrinology 147 (7) : 3598-3605. ScholarBank@NUS Repository. https://doi.org/10.1210/en.2006-0022|
|dc.description.abstract||Transcription of mammalian LH β-subunit genes (LHβ) is regulated by GnRH through activation of early growth response factor-1 (Egr-1), which interacts synergistically with steroidogenic factor-1 (Sf-1) and pituitary homeobox-1 (Pitx1) at the promoter; Egr-1 is thought to comprise the major mediator of this effect. However, the proximal promoters of LHβ genes in lower vertebrates lack an Egr-1 response element yet are responsive to GnRH; we demonstrate here that the promoter of the Chinook salmon LHβ (csLHβ) gene is also unresponsive to Egr-1. The homologous LHβ promoters in other fish contain a conserved estrogen response element-like sequence, which we recently demonstrated is not required for estrogen receptor (ER) α association with the csLHβ gene. Here we show that the estrogen response element-like element is required for the GnRH effect and for a response to c-jun overexpression. Using plasmid immunoprecipitation, we show that after GnRH exposure, c-jun associates with the intact csLHβ gene promoter through this element. We further show that the effect of c-jun requires its DNA-binding domain and that c-jun interacts with Sf-1 and ERα and exerts synergistic effects on promoter activity with Sf-1, ERα, and Pitx1. Finally, we demonstrate the role of c-jun in mediating the GnRH effect on this gene through knockdown of c-jun expression or use of a dominant negative. We conclude that c-jun mediation of the GnRH effect on the LHβ gene may be common in lower vertebrates and may have preceded an evolutionary divergence in the cis-regulatory elements that led to its function being replaced in mammals by Egr-1. Copyright © 2006 by The Endocrine Society.|
|Appears in Collections:||Staff Publications|
Show simple item record
Files in This Item:
There are no files associated with this item.
checked on May 19, 2022
WEB OF SCIENCETM
checked on May 12, 2022
checked on May 12, 2022
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.