Differences Exist between Eukaryotic and Prokaryotic Transcription

Important Differences Exist between Eukaryotic and Prokaryotic Transcription 

Although the basic mechanism by which RNA is synthesized is quite similar in prokaryotes and eukaryotes, several important differences occur. Most parts of the bacterial 

Comparison of Escherichia coli RNA Polymerase with DNA Polymerases I and III 

Product Single-strand RNAs Duplex DNA strands 

DNA are readily accessible to RNA polymerase binding and transcription. By contrast, most DNA in eukaryotic cells exists in a condensed form (chromatin), which is not readily accessible to transcription. The small fraction of DNA accessible to the RNA polymerase in any given cell type is especially sensitive to cleavage by mild treatment with bovine pancreatic DNase I. These regions of the DNA often contain bound RNA polymerase, modified histones, and additional nonhistone proteins. Active regions are often undermethylated compared with the total DNA. Most of the methylated groups in DNA are on the C residues in the CG sequence. 

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