Abstract
RNase H1 generally processes the RNA- DNA hybrids through non specific interaction between HBD and the ds RNA/DNA hybrid. There are no direct protein- protein interactions between the hybrid and HBD of RNase H1. The DNA binding region is highly conserved compared to RNA binding region and the Kd for RNA/DNA hybrid is less compared to ds RNA than to that of ds DNA [1]. HBD increases the processivity of RNase H1 and mutations in RNA binding region is tolerated compared to DBR. The RNA interacts between ɑ2 and β3 region with in the loop and with the protein in shallower minor groove.