Expression of RNase H of human hepatitis B virus polymerase in Escherichia coli

AIM To amplify HBV-RNase H gene fragment and expressionof RNase H for further use in the studies of HBV associatedliver diseases.METHODS:The encoding gene of HBV-RNase H wasseparately amplified for the first half and second half(H1and H2)by PCR from full length HBV gene and cloned intopT7Blue-T vector.Clones were first screened by digestionwith XbaⅠ and Hind Ⅲ enzyme for the correct size,andanalyzed further by DNA sequencing.The RNase H1 and H2fragments isolated from XbaⅠ and HindⅢ digestion productsof pT7 Blue-RNase H plasmid were ligated to the GSTagexpressing vectors separately,and expressed in E.coliBL21.The expressed proteins were checked by PAGE gel andWestern blot.RESULTS:Both H1 and H2 nucleotide seqences consistingof known genes and proteins,in correct size,were furtherconfirmed by Western blot to be the GST and RNase H1 orH2 fusion proteins.CONCLUSION:The successful cloning and expression ofHBV-RNase H will contribute to further research andapplication in HBV-associated diseases,