Structure and function of transcriptional activation domains.

Transcriptional activator proteins typically have distinct domains for the recognition of target genes (DNA-binding domains) and for stimulating the transcriptional machinery (activation domains). Although molecular models for the structure of activation domains are not yet available, clues are emerging from mutational analyses of many activators. Such domains may function at numerous steps in the transcription process, by making (and perhaps breaking) contacts with and among various basal transcription factors.