Hepatitis B virus (HBV) chronically infects approximately 350 million people worldwide. The replication of HBV which genome is only 3.2 kb long relies heavily on host factors. Previous studies demonstrated that a highly expressed liver-specific microRNA (miRNA) miR-122 suppresses HBV expression and replication in multiple ways. In this study, we found that the miR-122 response elements in viral...

CpG DNA methylation is one of the main epigenetic modifications playing a role in the control of gene expression. For DNA viruses whose genome has the ability to integrate in the host genome or to maintain as a latent episome, a correlation has been found between the extent of DNA methylation and viral quiescence. No information is available for Parvovirus B19, a human pathogenic virus, which i...

Abstract An estimated 296 million people worldwide suffer from chronic hepatitis B virus (HBV) infection, with 1.5 new infections occurring each year despite the availability of an effective vaccine. Chronic HBV infection persists in a dysfunctional immune environment, manifested by ineffective T cell response to virus. Patient HBV-specific CD8 +T cells have diminished proliferative capacity an...

6.1.1 Preface: CpG islands It is known that due to biochemical considerations that CpG, the pair of nocleotides C and G, appearing successively, in this order, along one DNA starnd, is relatively rare in DNA sequences, excluding particular sub-sequences, which are several hundreds of nucleotides long, where the couple CpG is more frequent. These sub-sequences, called CpG islands, are known to a...

Based on GC content and the observed/expected CpG ratio (oCpGr), we found three major groups among the members of subfamily Parvovirinae: Group I parvoviruses with low GC content and low oCpGr values, Group II with low GC content and high oCpGr values and Group III with high GC content and high oCpGr values. Porcine parvovirus belongs to Group I and it features an ascendant CpG distribution by ...

CpG islands were originally identified by epigenetic and functional properties, namely, absence of DNA methylation and frequent promoter association. However, this concept was quickly replaced by simple DNA sequence criteria, which allowed for genome-wide annotation of CpG islands in the absence of large-scale epigenetic datasets. Although widely used, the current CpG island criteria incur sign...

The complete genome sequences of hepatitis B virus (HBV) from 12 HBV-infected Yucpa Indians of Venezuela, a group with highly endemic HBV, were amplified and sequenced. The 12 isolates were closely related to each other, with 98.6-100% nucleotide identity. A phylogenetic tree based on the complete genome indicated clearly that they were genotype F. Three individuals had evidence of infection wi...

background although certain hbv mutations are known to affect the expression of hepatitis e antigen, their association with hbv viral level or clinical outcomes is less clear. objectives we evaluated associations between different mutations in the basal core promoter (bcp) and pre-core (pc) regions of hbv genome and subsequent changes in hbv viral dna level over seven years in a population of u...

Integration of hepatitis B virus (HBV) DNA into the human liver cell genome is believed to promote HBV-related carcinogenesis. This study aimed to quantify the integration of HBV DNA into the leukocyte genome in hepatocellular carcinoma (HCC) patients in order to identify potential biomarkers for HBV-related diseases. Whole-genome comparative genomic hybridization (CGH) chip array analyses were...

The CRISPR/Cas9 system is a novel genome editing technology which has been successfully used to inhibit HBV replication. Here, we described a novel gRNA-microRNA (miRNA)-gRNA ternary cassette driven by a single U6 promoter. With an anti-HBV pri-miR31 mimic integrated between two HBV-specific gRNAs, both gRNAs could be separated from the long transcript of gRNA-miR-HBV-gRNA ternary cassette thro...