In the field of molecular biology, nuclear receptors are a class of proteins found within cells that are responsible for sensing steroid and thyroid hormones and certain other molecules. In response, these receptors work with other proteins to regulate the expression of specific genes, thereby controlling the development, homeostasis, and metabolism of the organism. Nuclear receptors have the ability to directly bind to DNA and regulate the expression of adjacent genes, hence these receptors are classified as transcription factors. The regulation of gene expression by nuclear receptors generally only happens when a ligand is present. More specifically, ligand binding to a nuclear receptor results in a conformational change in the receptor, which, in turn, activates the receptor, resulting in up- or down-regulation of gene expression. A unique property of nuclear receptors that differentiates them from other classes of receptors is their ability to directly interact with and control the expression of genomic DNA. As a consequence, nuclear receptors play key roles in both embryonic development and adult homeostasis. As discussed below, nuclear receptors may be classified according to either mechanism or homology. [From Wikipedia, the free encyclopedia] b7a c91 fc2 f4a db8 cd6 a2e db8 cd6 cd6 a7b feb d2d a2e a7b a7b cd6 a2e is not affected in human cd6 e72 e72 a7b d2d d2d d93 a7b a7b c02 a9d inhibition fc2 a7b a9d ed4 db8 feb c2d inhibition c52 cd6 a7b during fasting ce9 a10 feb a2e fc2 d93 a7b cd6 cd6 db8 ed4 cd6 cd6 b04 bdd d52 a7b cd6 a7b feb a7b cd6 feb a9d a9d cc6 aca a2e a7b plays a role in translocation of CAR a2e a7b cd6 a2e ed4 a7b e65 cd6 be4 a7b a2e ef9 feb feb feb a2e ef9 e72 fc2 a7b a2e ef9 fc2 a2e ef9 e35 a2e ef9 b16 ef9 feb dc0 feb a2e ef9 e72 fc2 d47 c85 feb fc2 ef9 a2e e72 Omeprazole, TCDD, PCB Omeprazole, TCDD, PCB Omeprazole, TCDD, PCB a7b b04 in mice (possibly also in humans?) b04 b04 b04 b04 b04 b04 b04 b04 b04 b04 b04 b04 b04 b04 b04 b04 b04 b04 b04 b04 b04 dfc df0 dfc a2e dfc dfc a2e dfc dfc bdd d52 f4a cb1 f4a f4a bdd d52 bdd d52 cd6 cd6 cd6 aca bdd d52 db8 db8 db8 db8 a7b a7b a7b a7b a2e a2e a2e c02 cd6 cd6 cd6 df0 f65 f65 f65 f65 f65 f65 f65 f65 d93 d93 d93 d93 f65 a9d f65 d93 dfc a9d T3 c6d f4a T3 T3 d34 T3 T3

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