Transcription through the nucleosome.

Eukaryotic genomic DNA is wrapped around the histone octamer and forms the nucleosome, which is the basic unit of chromatin. Nevertheless, eukaryotic RNA polymerases transcribe the DNA that is tightly bound to the histone core in the nucleosome. For transcription to proceed on the nucleosome, the RNA polymerases must overcome the tight contacts between histones and DNA during transcription elongation. Here, we review the structural and biochemical studies of the transcription mechanism on the nucleosome, and focus on recent information to understand how RNA polymerases transcribe the genomic DNA in chromatin.