Hormones, receptor binding

More subtle modes of action are also possible since the response to hormone receptor binding is complex and could be affected by chemical interference with receptor-related proteins, DNA methylation or histone acetylation. Dioxin (TCDD), for example, reduces the ability of the oestrogen-receptor complex to bind to the oestrogen response element of DNA, reducing gene transcription. ... 

As summarized in Figure 52-3, steroid/thyroid hormone receptors bind to other proteins as well as to DNA [7-9]. 

Figure 7.4 The effect of bile acids on energy expenditure. Circulating bile acids bind to the G-protein-coupled receptor, TGR5 that stimulates increased cAMP-PKA activation and increased expression of type-2 iodothyronine deiodinase (D2). This response is sensitised by a high-fat diet. D2 converts thyroxine (T4) to active 3,5,3 -tri-iodothyronine (T3). T3 stimulates thyroid hormone receptor binding to target genes. This leads to altered expression of genes associated with energy balance, and increased energy expenditure.

When rats were administered atrazine in drinking water at 0.1, 0.2, or 0.5 g/1 for 1 or 3 weeks, they excreted as the principal metabolite 2 -chloro-4-ethylamino-6-amino-s-triazine. Atrazine and its metabolites have been shown to alter the activity of some testosterone-metabolizing enzymes in the rat pituitary and hypothalamus and to decrease hormone-receptor binding in the prostate. ... 

The first crystal structure of the LED of the AR in complex with metri-bolone (R1881) was solved by Matias and colleagues in 2000 [38]. The LED has a similar three-dimensional structure to the other agonist-bound steroid receptors, namely the ERa, ERj6 and the PR [38]. The fact that all steroid hormone receptors bind similar hormone response elements (HREs) stands in sharp contrast to the specific activities elicited by application of the steroid... 

Cellular localization of growth hormone receptors/binding protein... 

However, the levels of Gsa, Gia-1, Gia-2, Gia-3, Goa, and Gp were also shown to be unaltered in myocardium from SHRs, and adenylyl cyclase activity stimulated by PGEi, glucagon, and isoproterenol was reduced in SHRs, whereas FSK-stimulated enzyme activity was greater in SHRs as compared to WKY (McLellan et al. 1993). On the other hand, a diminished stimulation of adenylyl cyclase by stimulatory hormones, guanine nucleotides, FSK, and NaF in aorta and heart sarcolemma from SHRs (Anand-Srivastava 1992), renal hypertensive rats (Anand-Srivastava 1988) 1K1C HRs (Ge et al. 1999, 2006), and DOCA-salt HRs (Anand-Srivastava et al. 1993) has been demonstrated The reduction in the hormone receptor binding sites may be one of the possible mechanisms responsible for such an impaired response of hormones (Limas and Limas 1978 Woodcock et al. 

Blocked Hamster. Biol of Reprod 25 298-302 Adams TE, Norman RL, Spies HG (1981) Gonadotropin-Releasing Hormone Receptor Binding and Pituitary Responsiveness in Estradiol-Primed Monkeys. Science 213 1388-1390... 

Hormone-Receptor Binding Energetics The Binding Hot-Spot Concept... 155... 

Cadmium i Hormone/receptor-binding capacity to DNA Rat liver (in vivo) 57, 58, 62... 

Thyroid hormone receptors bind their sites on the promoter regions of DNA in the absence of bonnd hormone, usually resulting in transcriptional repression. 

Graves disease. Hyperthyroidism associated with diffuse hyperplastic goitre resulting from production of a thyroid-stimulating hormone receptor binding autoantibody. 

Modulator of steroid-hormone receptor binds with hsp90, GC receptor and dynein at different sites phosphorylated by casein kinase II. 

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