Abstract
The retinoic acid receptor (RAR) requires coregulators to bind effectively to response elements in target genes. A strategy of sequential screening of expression libraries with a retinoic acid response element and RAR identified a cDNA encoding a coregulator highly related to RXR alpha.
This protein, termed RXR beta, forms heterodimers with RAR, preferentially increasing its DNA binding and transcriptional activity on promoters containing retinoic acid, but not thyroid hormone or vitamin D, response elements.
Remarkably, RXR beta also heterodimerizes with the thyroid hormone and vitamin D receptors, increasing both DNA binding and transcriptional function on their respective response elements. RXR alpha also forms heterodimers with these receptors.
These observations suggest that retinoid X receptors meet the criteria for biochemically characterized cellular coregulators and serve to selectively target the high affinity binding of retinoic acid, thyroid hormone, and vitamin D receptors to their cognate DNA response elements.
See also:
- All-Trans-Retinoic Acid (ATRA - analogues and/or derivatives);
- The Di Bella Method (A Fixed Part - All-Trans Retinoic Acid, Analogues and/or Derivatives);
- Solution of retinoids in vitamin E in the Di Bella Method biological multitherapy;
- The Di Bella Method (A Fixed Part - Alpha tocopheryl acetate/Vitamin E);
- Vitamin D (analogues and/or derivatives) and cancer;
- The Di Bella Method (A Fixed Part - Dihydrotachysterol, Alfacalcidol, synthetic Vitamin D3);
- The Di Bella Method (A Fixed Part - Calcium, 2 grams per day, orally);
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- Complete objective response to biological therapy of plurifocal breast carcinoma;
- Neuroblastoma: Complete objective response to biological treatment;
- Oesophageal squamocellular carcinoma: a complete and objective response;