共查询到20条相似文献,搜索用时 31 毫秒
1.
2.
3.
4.
5.
6.
Molecular mechanism of estrogen receptor (ER)alpha-specific, estradiol-dependent expression of the progesterone receptor (PR) B-isoform 总被引:3,自引:0,他引:3
Flötotto T Niederacher D Hohmann D Heimerzheim T Dall P Djahansouzi S Bender HG Hanstein B 《The Journal of steroid biochemistry and molecular biology》2004,88(2):131-142
7.
8.
9.
DeNardo DG Kim HT Hilsenbeck S Cuba V Tsimelzon A Brown PH 《Molecular endocrinology (Baltimore, Md.)》2005,19(2):362-378
10.
11.
12.
Calmodulin is a selective modulator of estrogen receptors 总被引:5,自引:0,他引:5
García Pedrero JM Del Rio B Martínez-Campa C Muramatsu M Lazo PS Ramos S 《Molecular endocrinology (Baltimore, Md.)》2002,16(5):947-960
In the search for differences between ERalpha and ERbeta, we analyzed the interaction of both receptors with calmodulin (CaM) and demonstrated that ERalpha but not ERbeta directly interacts with CaM. Using transiently transfected HeLa cells, we examined the effect of the CaM antagonist N-(6-aminohexyl)-5-chloro-naphthalene sulfonilamide hydrochloride (W7) on the transactivation properties of ERalpha and ERbeta in promoters containing either estrogen response elements or activator protein 1 elements. Transactivation by ERalpha was dose-dependently inhibited by W7, whereas that of ERbeta was not inhibited or even activated at low W7 concentrations. In agreement with these results, transactivation of an estrogen response element containing promoter in MCF-7 cells (which express a high ERalpha/ERbeta ratio) was also inhibited by W7. In contrast, transactivation in T47D cells (which express a low ERalpha/ERbeta ratio) was not affected by this CaM antagonist. The sensitivity of MCF-7 cells to W7 was abolished when cells were transfected with increasing amounts of ERbeta, indicating that the sensitivity to CaM antagonists of estrogen-responsive tissues correlates with a high ERalpha/ERbeta ratio. Finally, substitution of lysine residues 302 and 303 of ERalpha for glycine rendered a mutant ERalpha unable to interact with CaM whose transactivation activity became insensitive to W7. Our results indicate that CaM antagonists are selective modulators of ER able to inhibit ERalpha-mediated activity, whereas ERbeta actions were not affected or even potentiated by W7. 相似文献
13.
14.
15.
BRCA1 suppresses osteopontin-mediated breast cancer 总被引:4,自引:0,他引:4
El-Tanani MK Campbell FC Crowe P Erwin P Harkin DP Pharoah P Ponder B Rudland PS 《The Journal of biological chemistry》2006,281(36):26587-26601
16.
17.
18.
Matthews J Wihlén B Heldring N MacPherson L Helguero L Treuter E Haldosén LA Gustafsson JA 《The Biochemical journal》2007,406(2):343-353
In the present study we examined the ability of 3,3',4,4',5-pentachlorinated biphenyl [PCB126 (polychlorinated biphenyl 126)], a prototypical AHR (aryl hydrocarbon receptor) agonist, and 2,2',4,6,6'-PCB (PCB104), which does not activate AHR, to induce the recruitment of ERalpha (oestrogen receptor alpha) to CYP1A1 (cytochrome P4501A1 gene) and CYP1B1 promoters in T-47D human breast cancer cells and other cell lines. PCB126 treatment strongly induced CYP1A1 and CYP1B1 mRNA expression that was unaffected by co-treatment with E2 (17beta-oestradiol). PCB104 failed to induce changes in either CYP1A1 or CYP1B1 expression levels. ChIP (chromatin immunoprecipitation) assays show that PCB126, but not PCB104, increased the promoter occupancy by ERalpha to CYP1A1 and CYP1B1 promoters. Co-treatment with PCB126+E2 significantly enhanced the promoter occupancy of ERalpha at CYP1A1, whereas co-treatment with PCB126+4-hydroxytamoxifen or ICI182,780 did not. Competitive binding studies revealed that neither PCB126 nor PCB104 bound to ERalpha. HEK-293 cells (human embryonic kidney-293 cells) stably transfected with ERalpha showed significantly higher PCB126-induced CYP1A1 expression compared with empty vector controls, whereas no increase was observed in cells stably transfected with ERalpha lacking its N-terminal AF1 (activation function-1) domain (ERalphaDeltaAF1). Despite no increase in AHR-mediated gene expression, ChIP assays revealed that ERalphaDeltaAF1 was present at CYP1A1 and CYP1B1 promoters. HC11 mouse mammary cells stably expressing shRNA (small-hairpin RNA) against ERalpha showed an 8-fold reduction in PCB126-dependent Cyp1a1 expression. Our results provide further evidence that AHR agonists induce ERalpha promoter occupancy at AHR target genes through indirect activation of ERalpha, and support a role for ERalpha in AHR transactivation. 相似文献
19.
20.
The estrogen receptor enhances AP-1 activity by two distinct mechanisms with different requirements for receptor transactivation functions. 总被引:13,自引:0,他引:13
P Webb P Nguyen C Valentine G N Lopez G R Kwok E McInerney B S Katzenellenbogen E Enmark J A Gustafsson S Nilsson P J Kushner 《Molecular endocrinology (Baltimore, Md.)》1999,13(10):1672-1685