Hepatitis B virus (HBV), an international public health concern, is a leading viral cause of
liver disease, such as
hepatocellular carcinoma. Sequence-specific
ribozymes derived from
ribonuclease P (
RNase P)
catalytic RNA are being explored for gene targeting applications. In this study, we engineered an active
RNase P ribozyme, M1-S-A, targeting the overlapping region of HBV S
mRNA, pre-S/L
mRNA, and pregenomic
RNA (
pgRNA), all deemed essential for
viral infection.
Ribozyme M1-S-A cleaved the S
mRNA sequence efficiently in vitro. We studied the effect of
RNase P ribozyme on HBV gene expression and replication using the human hepatocyte HepG2.2.15 culture model that harbors an HBV genome and supports HBV replication. In these cultured cells, the expression of M1-S-A resulted in a reduction of more than 80% in both HBV
RNA and
protein levels and an inhibition of about 300-fold in the capsid-associated HBV
DNA levels when compared to the cells that did not express any
ribozymes. In control experiments, cells expressing an inactive control
ribozyme displayed little impact on HBV
RNA and
protein levels, and on capsid-associated
viral DNA levels. Our study signifies that
RNase P ribozyme can suppress HBV gene expression and replication, implying the promise of
RNase P ribozymes for anti-HBV
therapy.