The mechanism of action of steroid hormones involves their interaction with tissue-specific binding sites, and results in a precise modulation of gene expression. Both high-affinity receptors and secondary binding sites exist for steroid hormones in target tissues. Only steroid-receptor complexes were, in several cases, clearly shown to directly regulate transcription by interacting with DNA region(s) close to steroid-controlled genes. However other indications suggest that steroid hormones

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... d also modulate transcription by altering chromatin conformation. These modifications encompass post-traductional modifications of histones and non-histone proteins, as well as changes in the pattern of histone variants. Beside transcription, there are also evidences that steroid hormones car modulate gene expression by regulating some RNA processing events. Whether highaffinity receptors or secondary binding sites directly regulate these events is not known. These observations however suggest that several levels of control might exist for steroid hormones to precisely regulate gene expression. C. ― DNA signals for transcription D. ― Interaction of steroid-receptors with enhancer-like DNA sequences E. -Steroidal control of chromatin organization 1. -DNA methylation 2. -Alteration of nucleosome structure 3. -Involvement of non-histone proteins Steroidal control of the processing of the transcript