Steroid receptor family

Hsps serve other ftmctions during nonstressful conditions. Hsp90 acts as a molecular brake for the steroid receptor family (Bresnick et al., 1988 Bagchi et al., 1990,1991). The complex of hsp90 and the glucocorticoid receptor prevents DNA binding of the receptor until the ligand for the receptor is present (Cadepond et al.,... 

Carson-Jurica, M.A., Schrader, W.T., O Malley, B.W. (1990) Steroid receptor family—structure and functions. Endocr. Rev. 11, 201-220. 

Figure 17.3 The nuclear receptor superfamily. Steroid receptor family members and thyroid receptor family members differ in several structural and functional properties. The estrogen receptors share properties with both steroid and thyroid receptor families and are likely an evolutionary precursor to both families.

In contrast to the steroid receptor family, members of the thyroid receptor family typically do not associate with accessory proteins and are not localized to the extranucleus matrix. Rather, these receptors exist in the basal state associated with chromatin in the cell nucleus. When bound by hormone ligand, thyroid receptor family members dissociate from the chromatin and typically form heterodimeric combinations with the retinoid-X receptor (RXR). RXR also is capable of homodimerization in association with its ligand 9-cis retinoic acid. Thus high 9-cis retinoic acid levels apparently promote homodimerization, and low levels are permissive of heterodimerization of RXR with activation by the partner ligand. 

ER is a transcription factor belonging to the steroid receptor family. At least two structurally different subtypes (ERa and ER(3) have been described in mammals, and these monomers form homo or heterodimers in cells. Another subtype (ERy) may possibly exist in fish (Drummond et al., 2002). ER has been used as recognition element for endocrine disrupters (exogenous chemicals, or mixtures of compounds, that are able to modify the functioning of the female sex steroid modulated endocrine... 

M. A. Carson-Jurica, W. T. Schrader, and B. W. O Malley Steroid receptor family structure and functions. Endocrine Reviews 11,201 (1990)... 

The steroid receptor family inclndes androgen receptors (AR), estrogen receptors (ER, a. and (3), progesterone receptors (PR, A and B), glncocorticoid receptors (GR), and mineralocorticoid receptors (MR). Traditional models propose that, upon binding their hormonal ligand, the receptors release heat shock proteins like hsp90, translocate into the nucleus, and bind as homodimers to imperfect palindromic response elements at upstream promoter sites. 

The steroid receptor family is a subclass of nuclear hormone receptors activated by steroid hormones. This nuclear hormone receptor subfamily has six members ... 

Carson-Jurica MA, Schrader WT, O Malley BW. Steroid receptor family structure and functions. Endocr Rev 1990 11 201-220. 

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