[EFFECTIVENESS OF POLYCATIONIC NANOPARTICLES OF POLYETHYLENEIMINE-POLYHYDROZIDE-CHITOSAN (PEI-PG-OCHG) AS A VECTOR FOR SMALL INTER- FERING RNA, DIRECTED TO SUPPRESS HERPES SIMPLEX TYPE 2 VIRUS REPLICATION].

AIM: Evaluation of an antiviral effect of miRNA in the nanoparticles of a polycationic compound against mRNA of vp16 protein (UL48 gene) of herpes simplex virus type 2 (HSV-2) in vitro. MATERIALS AND METHODS. 50% aqueous solution of polyethyleneimine (BDH, Great Britain), chitosan, containing approximately 15% of N-acetylated glucosamine chains (Sonat, Russia), hydrazine-hydrate and other chemical reagents (Chimmed, Russia); Vero continuous cell line, MS HSV-2 virus were used. Vero cells were cultivated in DMEM medium supplemented by 10% fetal bovine serum at 37°C in the atmosphere of 5% CO2. Cell viability was evaluated by using Neutral Red vital stain and MTT-test. Primers and probes for RT-PCR were modeled in Vector NTI 8.0 computer program according to the mRNA sequences of the studied genes (the sequences were obtained from GenBank) and synthesized in Sintol (Russia). RT-PCR tests were set using a standard procedure. Synthesis of PEI-PG-chitosan was carried out by Krivtsov G.G. et al. (2010). RESULTS: A design and synthesis of nucleotide sequences, that have interfering activity against this virus, was carried out to study the effect of siRNA on HSV-2 virus replication. During simultaneous addition of HSV-2 and specific siRNA to Vero cells in cell culture, a significant (by 4 lg) reduction of virus yield was observed. A level of UL48 mRNA expression level was determined after the influence of various siRNA variants. A S2 siRNA variant was shown to cause the most pronounced virus-inhibiting effect, aiming for the center of RNA-target (the level of expression of the studied gene decreased by 0.5 lg). CONCLUSION: siRNA in the PEI-PG-chitosan complexes were established to possess in vitro pronounced suppressive HSV-2 replication activity. The results obtained could be used in creation of new therapeutic preparation against herpes viruses.

Developmental and cell-cycle regulation of Caenorhabditis elegans HCF phosphorylation.

HCF-1 is a mammalian protein required for cell proliferation. It is also involved in transcriptional activation of herpes-simplex-virus immediate-early gene transcription in association with the viral transactivator VP16. HCF-1 and a related protein called HCF-2 possess a homologue in Caenorhabditis elegans that can associate with and activate VP16. Here, we demonstrate developmental regulation of C. elegans HCF (CeHCF) phosphorylation: a hyperphosphorylated form of CeHCF is present in embryos, whereas a hypophosphorylated form is present in L1 larvae. The phosphorylation patterns of endogenous CeHCF in worms and ectopically synthesized CeHCF in mammalian cells are remarkably similar, suggesting that the way CeHCF can be recognized by kinases is conserved in animals. Phosphorylation-site mapping of endogenous CeHCF, however, revealed that phosphorylation occurs at four clustered sites in the region of the protein that is not highly conserved among HCF proteins and is not required for VP16-induced complex formation. Indeed, phosphorylation of either CeHCF or human HCF-1 appears to be dispensable for association with VP16. All four CeHCF phosphorylation sites match the consensus recognition site for the cell-cycle kinases CDC2 and CDK2. Consistent with this similarity and with the developmental phosphorylation of CeHCF in C. elegans embryos, CeHCF phosphorylation is cell-cycle-regulated in mammalian cells.

Herpes simplex virus type 1 immediate early gene expression is stimulated by inhibition of protein synthesis.

Herpes simplex virus type 1 (HSV-1) transcription can be arrested at the immediate early (IE) stage by continuous treatment of cells with inhibitors of protein synthesis, usually cycloheximide, from the time of infection. We have analysed the effect of cycloheximide on IE gene expression with HSV-1 mutants deficient in the production of functional levels of the three major transactivators, the virion protein (VP16) and two IE proteins (ICP0 and ICP4). Expression from the HSV-1 IE promoters that control synthesis of ICP0 and ICP27 was, unexpectedly, stimulated by inhibition of protein synthesis. The effect was observed for the ICP0 promoter in its normal genome location and also when cloned upstream of the Escherichia coli lacZ coding sequences and inserted into the viral thymidine kinase locus. Expression from the human cytomegalovirus major IE promoter, when cloned into the genome of HSV-1 mutants, was also increased by inhibition of protein synthesis. Cycloheximide did not affect the intracellular stability of lacZ-specific RNA, suggesting that the response represented an increase in mRNA production. Activation of the ICP0 promoter was observed when protein synthesis was blocked by alternative agents. Since inhibitors of protein synthesis are known to activate cellular signal transduction pathways, our findings demonstrate new mechanisms for the regulation of HSV-1 IE gene expression which may be important during latency and reactivation. The results also highlight previously unrecognized difficulties in analysing the intrinsic activities of promoters when cloned into the HSV-1 genome.