Near promoters, both nucleosomes and CpG sites form characteristic spatial patterns. Previously, nucleosome depleted regions were observed upstream of transcription start sites and nucleosome occupancy was reported to correlate both with CpG density and the level of CpG methylation. Several studies imply a causal link where CpG methylation might induce nucleosome formation, whereas others argue...

DNA methylation of CpG islands plays a crucial role in the regulation of gene expression. More than half of all human promoters contain CpG islands with a tissue-specific methylation pattern in differentiated cells. Still today, the whole process of how DNA methyltransferases determine which region should be methylated is not completely revealed. There are many hypotheses of which genomic featu...

Although CpG dinucleotides remain the primary site for DNA methylation in mammals, there is emerging evidence that DNA methylation at non-CpG sites (CpA, CpT and CpC) is not only present in mammalian cells, but may play a unique role in the regulation of gene expression. For some time it has been known that non-CpG methylation is abundant in plants and present in mammalian embryonic stem cells,...

Vertebrate genomes are highly methylated at cytosine residues in CpG sequences. CpG methylation plays an important role in epigenetic gene silencing and genome stability. Compared with other epigenetic modifications, CpG methylation is thought to be relatively stable; however, it is sometimes affected by environmental changes, leading to epigenetic instability and disease. CpG methylation is re...

background: hepatitis b virus (hbv) causes acute and chronic liver disease worldwide. hbv has eight genotypes (a to h) which is the reflection of its genome with their characteristic geographical distribution. each genotype could have different pathogenic and therapeutic characteristics. there have been few records on hbv genotyping in general population from our region. this study aimed to det...

conclusions the main and frequent hbv genotype among azerbaijani patients with chronic hepatitis b virus infection was genotype d followed by genotype a. results the mean age of patients was 35.9 ± 11.7 years (19-66). of 103 patients, 72 (69.9%) were male. in the present study, the predominant hbv genotype was d (93.2%) followed by genotype a (5.8%) and concurrent infection with a and d genotyp...

BACKGROUND Regions with abundant GC nucleotides, a high CpG number, and a length greater than 200 bp in a genome are often referred to as CpG islands. These islands are usually located in the 5' end of genes. Recently, several algorithms for the prediction of CpG islands have been proposed. METHODOLOGY/PRINCIPAL FINDINGS We propose here a new method called CPSORL to predict CpG islands, which...

The members of the viral family Hepadnaviridae comprise one of the smallest enveloped DNA viruses and cause acute and chronic infections in mammals and birds, leading to large virus and antigen loads in the blood. They have a restricted host range and depend on differentiated hepatocytes for replication. Hepatitis B virus (HBV) is the prototype of the Hepadnaviridae. HBV can persist in infected...

Integration of the viral DNA into host chromosomes was found in most of the hepatitis B virus (HBV)-related hepatocellular carcinomas (HCCs). Here we devised a massive anchored parallel sequencing (MAPS) method using next-generation sequencing to isolate and sequence HBV integrants. Applying MAPS to 40 pairs of HBV-related HCC tissues (cancer and adjacent tissues), we identified 296 HBV integra...

CpG islands are distinguishable from the bulk of vertebrate DNA for being unmethylated and CpG-rich. Since CpG doublets are the specific target of eukaryotic DNA methyltransferases, CpG-rich sequences might be expected to be good methyl-accepting substrates in vitro, despite their unmethylated in vivo condition. This was tested using a partially purified DNA-methyltransferase from human placent...