Active repression by unliganded retinoid receptors in development

Active repression by unliganded retinoid receptors in development: less is sometimes more

N-CoR is required for patterning the anterior–posterior axis of zebrafish hindbrain by actively repressing retinoid signaling

Active repression of gene expression mediated by unliganded nuclear receptors plays crucial roles in early development of vertebrates. N-CoR (nuclear receptor co-repressor) is the first identified co-repressor that can repress retinoic acid (RA) inducible gene transcription in the absence of RA. Previously, N-CoR was reported to be required for late-stage organogenesis in mouse but whether N-Co...

Recruitment of N-CoR/SMRT-TBLR1 corepressor complex by unliganded thyroid hormone receptor for gene repression during frog development.

The corepressors N-CoR (nuclear receptor corepressor) and SMRT (silencing mediator for retinoid and thyroid hormone receptors) interact with unliganded nuclear hormone receptors, including thyroid hormone (T(3)) receptor (TR). Several N-CoR/SMRT complexes containing histone deacetylases have been purified. The best studied among them are N-CoR/SMRT complexes containing TBL1 (transducin beta-lik...

Unliganded thyroid hormone receptor inhibits formation of a functional preinitiation complex: implications for active repression.

The thyroid hormone receptor (TR) belongs to the steroid/nuclear receptor superfamily of ligand-inducible transcription factors. Numerous studies using transient transfection assays have demonstrated that in the absence of thyroid hormone (T3), unliganded TR acts as a constitutive repressor of transcription on genes bearing TR-response elements. We examined the molecular mechanism of TR repress...

Retinoid metabolizing enzymes in development.

It has long been known that retinoids are necessary for normal embryogenesis. To understand the role of retinoids in this process, it is important to elucidate the retinoid signalling pathway. The retinoid signal transduction pathway consists of three major components: (i) the metabolism of biologically active retinoids, (ii) nuclear receptors which bind to and are activated by retinoids, and (...