Many viral genes contain core promoters with two basal control elements, the TATA box and the pyrimidine-rich initiator (Inr). However, the molecular mechanisms involved in transcription initiation from composite core promoters (TATA(+) Inr(+)) containing Inr elements are unclear. The Rous sarcoma virus (RSV) long terminal repeat (LTR) contains a transcriptionally potent enhancer and core promo...

We have demonstrated that the truncated hepatitis C (HCV) core protein with its C-terminal hydrophobic domains deleted is translocated to the nucleus of transfected cells (22). In this study, intact and truncated core proteins of HCV were transiently expressed in a human hepatoblastoma cell line, HepG2, and their effects on the expression of the chloramphenycol acethyl transferase (CAT) gene dr...

Functional analysis of naturally occurring hepatitis B virus (HBV) mutations is crucial in understanding their impact on disease. We have recently identified two mutations in the HBV core promoter of an HBV strain associated with fulminant hepatitis leading to highly (15-fold) enhanced replication as a result of increased viral encapsidation of pregenomic RNA into the core particles (T. F. Baum...

Cellular protein interaction networks are integral to host defence and immune signalling pathways, which are often hijacked by viruses via protein interactions. However, the comparative virus-host protein interaction networks and how these networks control host immunity and viral infection remain to be elucidated. Here, we mapped protein interactomes between human host and several influenza A v...

Adenoviruses target their double-stranded DNA genome and its associated core proteins to the interphase nucleus; this core structure then enters through the nuclear pore complex. We have used digitonin permeabilized cell import assays to study the cellular import factors involved in nuclear entry of virus DNA and the core proteins, protein V and protein VII. We show that inhibition of transport...

We describe a convenient, rapid, and reproducible method for labeling proteins in vitro by acetylation with [3H] or [14-C]acetic anhydride dissolved in small amounts of anhydrous dioxane. The reaction is carried out at neutral pH and does not require the use of detergents, water-immiscible organic solvents, oxidizing, or reducing agents. Thus undesirable solvent-induced alterations in protein s...

Pathogenic retroviruses have evolved multiple means for evading host restriction factors such as apolipoprotein B editing complex (APOBEC3) proteins. Here, we show that murine leukemia virus (MLV) has a unique means of counteracting APOBEC3 and other cytosolic sensors of viral nucleic acid. Using virus isolated from infected WT and APOBEC3 KO mice, we demonstrate that the MLV glycosylated Gag p...

Pestiviruses, including bovine viral diarrhea virus (BVDV), are important animal pathogens and close relatives of hepatitis C virus. Pestivirus particles are composed of an RNA genome, a host-derived lipid envelope, and four virion-encoded structural proteins, core (C), E(rns), E1, and E2. Core is a small, highly basic polypeptide that is processed by three enzymatic cleavages before its incorp...

Here we review the current knowledge on maturation of adenovirus, a non-enveloped icosahedral eukaryotic virus. The adenovirus dsDNA genome fills the capsid in complex with a large amount of histone-like viral proteins, forming the core. Maturation involves proteolytic cleavage of several capsid and core precursor proteins by the viral protease (AVP). AVP uses a peptide cleaved from one of its ...

DNA coding for the core antigen from hepatitis B Virus (HBcAg) was amplified, cloned and propagated in E. coli. The core protein was expressed in E. coli and the product was readily detected by Western blot. This protein can be used as a diagnostic material in serum screening tests. To increase the level of expression of this antigen in bacteria, two plasmids were constructed in which the gene ...