Linked Life Data

20155784

Source:http://linkedlifedata.com/resource/pubmed/id/20155784

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2010-4-30
pubmed:abstractText
Hepatitis B virus (HBV) causes liver diseases from acute hepatitis to cirrhosis and liver cancer. Currently, more than 350 million people are chronic HBV carriers, with devastating prognosis. HBV is a small enveloped noncytopathic virus, containing a circular partially double-stranded DNA genome, and exhibits strong tropism for human liver cells. Infected individuals (acute and chronic) secrete about 10(7) to 10(11) virions per day to the bloodstream, with each infected cell releasing 50-300 viruses per day. HBV infects nondividing hepatocytes and replicates by reverse-transcribing the pregenomic RNA to DNA in the host cells. The level of deoxyribonucleotide triphosphates (dNTPs) in nondividing cells is too low to support viral replication and enable the high yield of secreted virions. Here, we report production of dNTPs by viral-dependent transcription activation of R2, the key component of ribonucleotide reductase (RNR), and show that this process is critical for the HBV life-cycle. This was found in an established HBV-positive cell line and was reproduced by HBV DNA-transduced cells, in both culture and mice. Furthermore, the viral hepatitis B X protein is essential in activating R2 expression by blocking access of Regulatory factor x1, a repressor of the R2 gene. CONCLUSION: Our findings demonstrate that the hepatitis B X protein is critical in infecting nonproliferating hepatocytes, which contain a low dNTP level. In addition, we provide molecular evidence for a new mechanism of HBV-host cell interaction where RNR-R2, a critical cell-cycle gene, is selectively activated in nonproliferating cells. This mechanism may set the stage for formulating a new category of anti-HBV drugs.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
1527-3350
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
51
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1538-46
pubmed:meshHeading
pubmed:year
2010
pubmed:articleTitle
Hepatitis B virus activates deoxynucleotide synthesis in nondividing hepatocytes by targeting the R2 gene.
pubmed:affiliation
Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't