There are two hypotheses explaining a fulminant outcome after hepatitis B virus (HBV) infection, both of which may be applicable at the same time: (i) basal core promoter (BCP) mutations increase viral replication, allowing rapid spread of the virus through the liver, and (ii) pre-core (pre-C) mutations abrogating hepatitis B e antigen (HBeAg) synthesis remove its tolerogenic effect, leading to...

BACKGROUND More than two billion people have been exposed to hepatitis B virus (HBV) worldwide. Furthermore, four hundred million of them are infected with chronic HBV infection. The predominant mutation of the precore region involves a G to A change at nucleotide1896, which creates a premature stop codon at codon 28. Two mutations of A1762T and G1764A are reported as the most prevalent mutatio...

This experiment was conducted to compare the effects of prebiotic as alternative feed additive to an antibiotic growth promoter (bacitracin methylene disalicyate) on the growth performance and morphometrical parameters of the small intestine of broiler chickens. One hundred and forty four day old broiler chicks were randomly assigned to one of three dietary treatments for 6 wk and each treatmen...

Circadian rhythms in transcription are generated by rhythmic abundances and DNA binding activities of transcription factors. Propagation of rhythms to transcriptional initiation involves the core promoter, its chromatin state, and the basal transcription machinery. Here, I characterize core promoters and chromatin states of genes transcribed in a circadian manner in mouse liver and in Drosophil...

Eukaryotic transcription occurs in bursts that vary in size and frequency, but the contribution of individual core promoter elements to transcriptional bursting is not known. Here we analyze the relative contributions to bursting of the individual core promoter elements-CCAAT, TATAA-like, Sp1BS, and Inr-of an MHC class I gene in primary B-cells during both basal and activated transcription. The...

The mechanism responsible for hepatitis B virus (HBV) exacerbation during chemotherapy and radiotherapy remains unknown. We investigated whether the activation of DNA repair pathways influences HBV replication. The upregulation of the promyelocytic leukemia (PML) protein and its associated PML nuclear body (PML-NB) by chemotherapy and irradiation-induced DNA repair signaling correlated with the...

Eukaryotic transcriptional activators may function by stimulating formation of RNA polymerase II preinitiation complexes at the core promoter of genes. In this case, their mode of action will intrinsically depend on how these complexes assemble on promoters in living cells, an issue that remains largely unexplored. Here we show that in yeast the basal transcription machinery is brought to the p...

The RNA polymerase II core promoter is a structurally and functionally diverse transcriptional regulatory element. There are two main strategies for transcription initiation - focused and dispersed initiation. In focused initiation, transcription starts from a single nucleotide or within a cluster of several nucleotides, whereas in dispersed initiation, there are several weak transcription star...