Homo- and heterodimerization in transcriptional regulation.

Eukaryotic transcription factors bind DNA and typically serve to localize large multiprotein complexes to particular genes to up- or downregulate transcription, thereby coordinating cellular responses to a variety of signals. Different combinations of transcription factors within DNA-binding multiprotein complexes allow individual proteins to partake in multiple different regulatory pathways. Many transcription factors can form homo- and heterodimers (or oligomers) with different partners, thus modulating DNA-binding specificity and affinity and/or the recruitment of different binding partners. This chapter reviews several of the mechanisms by which the homo- and heterodimerization of transcription factors contributes to transcriptional regulation.