Nuclear hormone receptors (nuclear receptors) are specialised transcription factors which bind to specific sequences of DNA of particular target genes. They regulate transcription of these target genes in response to a variety of endogenous ligands. Nuclear receptors are classified into two major subfamilies: steroid and non-steroid hormone receptors. Steroid hormone receptors include receptors for estrogen (ER), androgen, glucocorticoid, mineralocorticoid and progesterone. Examples of non-steroid hormone receptors include thyroid receptors, retinoic acid receptors and peroxisome proliferator-activated receptors (PPAR). Researchers can save up to 50% on nuclear hormone receptor agonists, antagonists and modulators from Hello Bio - they are up to half the price of other suppliers.