Nuclear receptor superfamily features

Peroxisome Proliferator-Activated Receptors. Figure 1 Common structural and functional features of nuclear receptor transcription factors. Consistent with other members of the nuclear receptor superfamily, the PPARs have a modular domain structure consisting of domains A/B, C, D, and E. Each domain is associated with specific functions. 

In another recent example, Hashimoto reported photoaffinity experiments on retinoic acid receptors (RAR). Retinoic acid plays a critical role in cell proliferation and differentiation. RARs belong to the superfamily of nuclear/ thyroid hormone receptors. They consist of six transmembrane domains (A-F) which is a general feature of these receptors. The A/B domains have an autonomous transactivation function while the C-domain contains the Zn-finger, which binds to DNA. The large E-domain participates in ligand binding, dimerization, and ligand dependent transactivation. Finally, D- and F-domains help the orientation and stabilization of the E-domain. 

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