Structural transition of the nucleosome during chromatin remodeling and transcription.

In eukaryotes, the nucleosome is the basic unit of chromatin. Since the genomic DNA is tightly wrapped around the histone octamer in the nucleosome, its function is severely restricted in chromatin. To overcome the nucleosome barrier, the nucleosome structure must dynamically change during genomic DNA functions. Recent structural studies revealed that chromatin remodelers and RNA polymerase II drastically alter the nucleosome structures during the chromatin remodeling and transcription processes. These results provide important information for understanding how genes are properly regulated in eukaryotes. Here, we review the recent structural studies of nucleosome versatility and dynamics during chromatin remodeling and transcription by RNA polymerase II.