Final answer:
In bacterial cells, transcription is regulated by promoter elements, while in eukaryotic cells, transcription is more complex and involves additional regulatory elements such as enhancers and silencers. Eukaryotic cells also employ DNA bending proteins to facilitate long-distance regulation of gene expression.
Step-by-step explanation:
In bacterial cells, transcription is regulated by specific DNA sequences known as promoter elements which are recognized by RNA polymerase and other transcription factors. For example, the TATA box is a common promoter element in both bacterial and eukaryotic cells. In eukaryotic cells, however, transcription is more complex and involves additional regulatory elements such as enhancers and silencers. These regulatory elements can be located proximal or distal to the gene they regulate and interact with transcription factors to either enhance or repress transcription.
An important difference between bacterial and eukaryotic cells is the presence of DNA bending proteins in eukaryotes. These proteins facilitate the looping of DNA, allowing distant enhancer sequences to interact with the promoter region. This mechanism enables the regulation of gene expression over long genomic distances in eukaryotes.