Molecular Mechanisms of Thyroid Hormone Action: A Physiologic Perspective

This article reviews the major action that thyroid hormone exerts at the nuclear level by regulating the level of mRNAs of specific genes. There are at least three thyroid hormone receptor isoforms that mediate hormonal effects at the tissue level. Recent studies have shown an unexpected degree of complexity in the nature of the association of the triiodothyronine (T3) receptors and the DNA of target genes. They have shown the multiple interactions possible between the T3-receptor complex and other proteins participating in the process of gene regulation.