Which feature is indicative of a prokaryotic promoter structure?

The presence of consensus sequences is a key feature indicative of a prokaryotic promoter structure. Prokaryotic promoters typically contain specific, conserved regions of DNA that serve as recognition sites for RNA polymerase and transcription factors. These consensus sequences, such as the -10 (Pribnow box) and -35 regions, facilitate the binding of RNA polymerase, leading to the initiation of transcription. The presence of these sequences helps ensure that transcription occurs accurately and efficiently in response to various regulatory signals.

In contrast, features associated with introns are more characteristic of eukaryotic genes, which undergo splicing to remove these non-coding regions. A localized transcription complex is more commonly discussed in the context of eukaryotic transcription processes, where additional proteins and complex structures form around the RNA polymerase. Finally, high levels of post-transcriptional modifications, such as capping and polyadenylation, are also hallmarks of eukaryotic transcription and not prokaryotic transcription, which is generally more straightforward and does not involve these extensive modifications. Thus, consensus sequences are definitive of prokaryotic promoter structures, highlighting their role in facilitating transcription initiation.