alexa Retinoids and their receptors in differentiation, embryogenesis, and neoplasia.
Pharmaceutical Sciences

Pharmaceutical Sciences

Journal of Clinical & Experimental Pharmacology

Author(s): De Luca LM

Abstract Share this page

Abstract The crucial role of retinoids in controlling differentiation processes has become evident from studies conducted in a variety of in vivo and in vitro systems. Most striking is the role of retinoic acid as a morphogenic substance in vertebrate limb development, but equally important is its role in the maintenance of epithelial integrity in most superficial linings of the body. The similarity of the mode of action of retinoids to that of the steroid and thyroid hormones has recently been demonstrated with the discovery of the nuclear receptors for retinoic acid, which belong to the steroid/thyroid hormone receptor superfamily. These receptors act as transcriptional activators by binding as heterodimers to specific nucleotide sequences in the response elements of target genes. Response elements for retinoic acid have so far been identified for the rat growth hormone and phosphoenolpyruvate carboxykinase, the mouse complement H and laminin B1, the human and mouse retinoic acid receptor beta, the human osteocalcin, and the human alcohol dehydrogenase genes. The retinoic acid response element (RARE) for the rat growth hormone gene is also a thyroid hormone response element (TRE), and the AP-1 binding site of the human osteocalcin promoter is also a vitamin D response element (VDRE) and a RARE. Both these elements are palindromic. Other RAREs have a direct repeat configuration of the half-site motif AGGTCA separated by five nucleotides (AGGTCA xxxxx AGGTCA). The direct repeat arrangement of the same core motif AGGTCA separated by three or four nucleotides becomes a VDRE or TRE, respectively. A point mutation has been identified in the RAR alpha gene of embryonal carcinoma cells resistant to retinoic acid. In addition to the three retinoic acid receptors (alpha, beta, gamma) belonging to the steroid/thyroid hormone receptor superfamily, a second class of retinoid receptors (RXR) alpha, beta, gamma has also been characterized and its relatedness to a gene, XR2C, of the locus ultraspiracle required for pattern formation in Drosophila has been established. That would suggest that both vertebrates and invertebrates may require similar transcriptional activators during morphogenesis. An RXRE has been identified in the CRBPII gene promoter and it contains five repeats of the canonical sequence AGGTCA separated by one nucleotide. The importance of retinoids, both as chemopreventive agents of tumorigenesis and potent differentiation inducers of neoplastic cells, can only be emphasized by the recent finding that the t(15;17) (q21- q11-22) translocation, specifically associated with acute promyelocytic leukemia, also causes translocation of the retinoic acid receptor alpha gene and its fusion with with a new locus, myl, of unknown function.(ABSTRACT TRUNCATED AT 250 WORDS)
This article was published in FASEB J and referenced in Journal of Clinical & Experimental Pharmacology

Relevant Expert PPTs

Recommended Conferences

Relevant Topics

Peer Reviewed Journals
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals
International Conferences 2017-18
Meet Inspiring Speakers and Experts at our 3000+ Global Annual Meetings

Contact Us

Agri, Food, Aqua and Veterinary Science Journals

Dr. Krish

1-702-714-7001 Extn: 9040

Clinical and Biochemistry Journals

Datta A

1-702-714-7001Extn: 9037

Business & Management Journals


1-702-714-7001Extn: 9042

Chemical Engineering and Chemistry Journals

Gabriel Shaw

1-702-714-7001 Extn: 9040

Earth & Environmental Sciences

Katie Wilson

1-702-714-7001Extn: 9042

Engineering Journals

James Franklin

1-702-714-7001Extn: 9042

General Science and Health care Journals

Andrea Jason

1-702-714-7001Extn: 9043

Genetics and Molecular Biology Journals

Anna Melissa

1-702-714-7001 Extn: 9006

Immunology & Microbiology Journals

David Gorantl

1-702-714-7001Extn: 9014

Informatics Journals

Stephanie Skinner

1-702-714-7001Extn: 9039

Material Sciences Journals

Rachle Green

1-702-714-7001Extn: 9039

Mathematics and Physics Journals

Jim Willison

1-702-714-7001 Extn: 9042

Medical Journals

Nimmi Anna

1-702-714-7001 Extn: 9038

Neuroscience & Psychology Journals

Nathan T

1-702-714-7001Extn: 9041

Pharmaceutical Sciences Journals

John Behannon

1-702-714-7001Extn: 9007

Social & Political Science Journals

Steve Harry

1-702-714-7001 Extn: 9042

© 2008-2017 OMICS International - Open Access Publisher. Best viewed in Mozilla Firefox | Google Chrome | Above IE 7.0 version