Final answer:
Transcriptional activators interact with the transcriptional machinery in both prokaryotes and eukaryotes. In prokaryotes, activators interact with RNA polymerase and other proteins to initiate transcription at gene promoters. In eukaryotes, activators bind to enhancer regions and facilitate the recruitment of RNA polymerase and other transcription factors to the gene promoter.
Step-by-step explanation:
Transcriptional activators play a key role in attracting the transcriptional machinery in both prokaryotes and eukaryotes. In prokaryotes, activators interact with the RNA polymerase enzyme and other proteins to initiate transcription at specific gene promoters. In eukaryotes, activators bind to enhancer regions, which can be located far away from the gene, and facilitate the interaction between the activators and the transcription initiation complex. This interaction helps in the recruitment of RNA polymerase and other transcription factors to the gene promoter, enabling transcription to begin.