Ligand-independent activity

Schreihofer DA, Resnick EM, Lin VY, Shupnik MA (2001) Ligand-independent activation of pituitary ER dependence on PKA-stimulated pathways. Endocrinology 142 3361-3368... 

Ligand-Independent Activation of Steroid Hormone Receptors and Non-genomic Effects of Steroids... 

Power, R.F., Maui, S.K., Codina, J., Conneely, O.M.and O Malley, B.W. Dopaminergic and Ligand-independent activation of steroid hormone receptors (1991) Science 254,1636-1639... 

Interestingly, both Ras and Rasv12 induced the activation of transcription of ERP in the absence of E2. Such ligand-independent activation of Ras was not observed with ERa (Kato et al, 1995), although it was reported with EGF treatment (Bunone et al., 1996). A similar pattern of... 

The ligand-independent activation of AF-1 is presumed to be closely related to phosphorylation of steroid receptors by cellular protein kinases (Weigel, 1996). 

Our observations suggest that Ser-106 and Ser-124 are both required in vivo to fully recruit SRC-1. In addition, when cells were treated with factors known to activate Ras, such as EGF or IGF-1 (data not shown), the in vivo interaction between SRC-1 and ER(3 was also enhanced, thus mimicking the results obtained in the presence of activated Ras. This study demonstrates for the first time that phosphorylation of the AF-1 domain of a member of the nuclear receptor superfamily enhances the recruitment of a steroid receptor coactivator (SRC-1) and provides a molecular basis for ligand-independent activation of ER(3 via the MAPK cascade. 

Sablin EP, et al. Structural basis for ligand-independent activation of the orphan nuclear receptor LRH-1. Mol. Cell 99. 2003 11 1575-1585. 

Ligand-Dependent Versus Ligand-Independent Activation of the AhR... 

Lesca P, Peryt B, Larrieu G, Alvinerie M, Galtier P, et al. 1995. Evidence for the ligand-independent activation of the Ah receptor. Biochem. Biophys. Res. Comm. 209 474-82... 

Weigel NL, Zhang Y. 1998. Ligand-independent activation of steroid hormone receptors. J. Molec. Med. 76 469-79... 

Peroxisome proliferator activated receptors (PPARs) are members of the nuclear hormone receptors superfamily of ligand-activated transcription factors that are related to retinoid, steroid and thyroid receptors. All members of this superfamily have a similar structure the amino-terminal region allows ligand-independent activation, confers con-... 

The phosphorylation of nuclear receptors on Ser/Thr residues is a key mechanism for the coupling of nuclear receptor signaling to other signaling pathways of the cell. Many nuclear receptors are isolated as phosphoproteins, and their phosphorylation provides a means for ligand-independent activation and regulation. The steroid... 

Dussault, I., Lin, M., Hollister, K., Fan, M., Termini, J., Sherman, M. A., and Forman, B. M. (2002) A structural model of the constitutive androstane receptor defines novel interactions that mediate ligand-independent activity. Mol. Cell. Biol. 22 (15), 5270-5280. 

IV. Ligand-independent activation of mutant receptors (Section VII,C)... 

---