Heterodimer activators

X receptor heterodimer activates the phenobarbital-responsive enhancer module of the CYP2B gene. Molecular and Cellular Biology, 18,... 

Honkakoski, P., Zelko, I., Sueyoshi, T. and Negishi, M. (1998) The nuclear orphan receptor CAR-retinoid X receptor heterodimer activates the phenobarbital-responsive enhancer module of the CYP2B gene. Molecular and Cellular Biology, 18, 5652-5658. 

Nuclear Orphan Receptor CAR-Retinoid x Receptor Heterodimer Activates the Phenobar-bital-Responsive Enhancer Module of the CYP2B Gene. 

Farnesyl transferase from rat cells is a heterodimer consisting of a 48 kD u-snbnnit and a 46 kD /3-snbnnit. In the structure shown here, helices 2 to 15 of the u-snbnnit are folded into seven short coiled coils that together form a crescent-shaped envelope partially surrounding the /3-snbnnit. Twelve helices of the /3-snl> nnit form a novel barrel motif that creates the active site of the enzyme. Farnesyl transferase inhibitors, one of which is shown here, are potent suppressors of tumor growth in mice, but their value in humans has not been established. 

Abd Alla, S., Lother, H., and Quitterer, U. (2000). Atl-receptor heterodimers show enhanced G-protein activation and altered receptor sequestration. Nature 407 94-98. 

Sequence-specific transcription factors often bind as multimers especially as dimers to DNA. This allows binding of mirror-imaged sequences (palindromes) in the DNA that are separated by a few spacer nucleotides. The dimerization is stabilized by hydrophobic motifs within dimerization motifs of each transcription factor molecule. Dependent on the nature of the dimerization domain and the abundance of individual transcription factors homo- or heterodimers can form and bind to palindromes with differential activity. 

A peroxisome proliferator-activated receptor (PPAR) binding site was identified in the murine FATP1 promoter. Several reports have shown a positive regulation of mouse FATPs by ligands that activate PPAR-a, PPAR-y, or PPAR-y/RXR heterodimers. 

There is abundant experimental evidence suggesting that many (if not most) GPCRs exist as homodimers and/or heterodimers [4]. The functional significance of dimers and their role in G protein activation remains to be determined for most GPCRs. Experimental evidence suggests that dimers may play roles in processing and maturation of newly synthesized receptor protein. Heterodimers may contribute to pharmacologic... 

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