Crystal structure of RNA-DNA duplex provides insight into conformational changes induced by RNase H binding.
Davis, R.R., Shaban, N.M., Perrino, F.W., Hollis, T.(2015) Cell Cycle 14: 668-673
- PubMed: 25664393 
- DOI: https://doi.org/10.4161/15384101.2014.994996
- Primary Citation of Related Structures:  
4WKJ - PubMed Abstract: 
RNA-DNA hybrids play essential roles in a variety of biological processes, including DNA replication, transcription, and viral integration. Ribonucleotides incorporated within DNA are hydrolyzed by RNase H enzymes in a removal process that is necessary for maintaining genomic stability. In order to understand the structural determinants involved in recognition of a hybrid substrate by RNase H we have determined the crystal structure of a dodecameric non-polypurine/polypyrimidine tract RNA-DNA duplex. A comparison to the same sequence bound to RNase H, reveals structural changes to the duplex that include widening of the major groove to 12.5 Å from 4.2 Å and decreasing the degree of bending along the axis which may play a crucial role in the ribonucleotide recognition and cleavage mechanism within RNase H. This structure allows a direct comparison to be made about the conformational changes induced in RNA-DNA hybrids upon binding to RNase H and may provide insight into how dysfunction in the endonuclease causes disease.
Organizational Affiliation: 
a Department of Biochemistry; Center for Structural Biology ; Wake Forest School of Medicine ; Winston-Salem , NC USA.