FIGURE 6-20 Model of functional forms of the thyroid receptor. Thyroid receptors (TR) can bind to DNA as monomers, homodimers, or heterodimers. The heterodimer consists of one subunit of TR + one subunit of the retinoic acid receptor, either the RXR or RAR isoform. Another level of complexity involves whether the receptor ligand-binding domain is occupied with hormone. Thus, thyroxine binding to TR and 9-a's-retinoic acid binding to RXR can shift the equilibrium between homodimers and heterodimers, which can provide another level of regulation of the receptor interactions with specific response elements. [Modified with permission from Jameson, J. L., and DeGroot, L. J. (1995). Mechanisms of thyroid hormone action. In "Endocrinology" (L. J. DeGroot et al, eds.). Volume 1, Chapt. 37, pp. 583-601. W. B. Saunders, Philadelphia, PA.]
terol biosynthesis (HMG-CoA reductase), hormone systems (growth hormone, oxytocin, nerve growth factor), oxygen metabolism (cytochrome C oxidase), ion transport, and energy metabolism (Ca2+ ATPase, Na+, K+ ATPase).
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Everything you wanted to know about. How To Cure Tennis Elbow. Are you an athlete who suffers from tennis elbow? Contrary to popular opinion, most people who suffer from tennis elbow do not even play tennis. They get this condition, which is a torn tendon in the elbow, from the strain of using the same motions with the arm, repeatedly. If you have tennis elbow, you understand how the pain can disrupt your day.