Heterotypic dimerization

The heterotypic dimerization significantly expands the repertoire for tissue-specific regulation of transcription activity. The tissue-specific expression of a particular pattern of transcriptional activators can be used to select only certain DNA-binding elements out of a series of similar elements, and thus to specifically induce certain genes. This strategy is extensively used by the receptors for retinoic acid (see chapter 4). 

Lamb, P. and McKnight, S.L. Diversity and spedfidty in transcriptional regulation the benefits of heterotypic dimerization (1991) Trends Biochem. Sd. 16, 417-422... 

Analogous to heterotypical dimerization of transcription factors (see Chapter 1.2), heterologous dimerization is observed within different members of a receptor family. A certain growth hormone can thus bind to and activate different dimeric combinations of the members of a receptor family. Fig. 8.5. shows the possibilities for heterodimerization of receptors, using the PDGF receptor as an example (review Lemmon and Schlessinger, 1994). 

Lamb, P., and S. L. McKnight, Diversity and specificity in transcriptional regulation The benefits of heterotypic dimerization. Trends Biochem. Sci. 16 417-433, 1991. 

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