[Structural and Functional Organization of the Mitochondrial DNA Control Region in the Woolly Mammoth (Mammuthus primigenius)].

The woolly mammoth mitochondrial genome (including the Malolyakhovsky mammoth) has been previously sequenced, followed by the annotation of all its genes (MF770243). In this study, based on the Malolyakhovsky mammoth, we describe for the first time the sites of functional significance in the control region of the woolly mammoth mitogenome.

Preliminary Evaluation of a Bunyavirus Vector for Cancer Immunotherapy.

Replicon particles of Rift Valley fever virus, referred to as nonspreading Rift Valley fever virus (NSR), are intrinsically safe and highly immunogenic. Here, we demonstrate that NSR-infected human dendritic cells can activate CD8(+) T cells in vitro and that prophylactic and therapeutic vaccinations of mice with NSR encoding a tumor-associated CD8 peptide can control the outgrowth of lymphoma cells in vivo. These results suggest that the NSR system holds promise for cancer immunotherapy.

[Development of New Mitochondrial DNA Markers in Scots Pine (Pinus sylvestris L.) for Population Genetic and Phylogeographic Studies].

Fragments of genomic DNA of Scots pine (Pinus sylvestris L.) homologous to the mitochondrial DNA (mtDNA) contigs of Norway spruce (Picea abies (L.) Karst.) and loblolly pine (Pinus taeda L.) were resequenced in a sample of the Scots pine trees of European, Siberian, Mongolian and Caucasian origin in order to develop mtDNA markers. Flanking non-coding regions of some mitochondrial genes were also investigated and resequenced. Five single nucleotide polymorphisms (SNPs) and a single minisatellite locus were identified. Caucasian samples differed from the rest by three SNPs. Two SNPs have been linked to an early described marker in.the first intron of the nad7 gene, and all together revealed three haplotypes in European populations. No variable SNPs were found in the Siberian and Mongolian populations. The minisatellite locus contained 41 alleles across European, Siberian and Mongolian populations, but, this locus demonstrated a weak population differentiation (F(ST) = 0.058), probably due to its high mutation rate.

Evaluation of nonspreading Rift Valley fever virus as a vaccine vector using influenza virus hemagglutinin as a model antigen.

Virus replicon particles are capable of infection, genome replication and gene expression, but are unable to produce progeny virions, rendering their use inherently safe. By virtue of this unique combination of features, replicon particles hold great promise for vaccine applications. We previously developed replicon particles of Rift Valley fever virus (RVFV) and demonstrated their high efficacy as a RVFV vaccine in the natural target species. We have now investigated the feasibility of using this nonspreading RVFV (NSR) as a vaccine vector using influenza virus hemagglutinin as a model antigen. NSR particles were designed to express either the full-length hemagglutinin of influenza A virus H1N1 (NSR-HA) or the respective soluble ectodomain (NSR-sHA). The efficacies of the two NSR vector vaccines, applied via either the intramuscular or the intranasal route, were evaluated. A single vaccination with NSR-HA protected all mice from a lethal challenge dose, while vaccination with NSR-sHA was not protective. Interestingly, whereas intramuscular vaccination elicited superior systemic immune responses, intranasal vaccination provided optimal clinical protection.

Comparative efficacy of two next-generation Rift Valley fever vaccines.

Rift Valley fever virus (RVFV) is a re-emerging zoonotic bunyavirus of the genus Phlebovirus. A natural isolate containing a large attenuating deletion in the small (S) genome segment previously yielded a highly effective vaccine virus, named Clone 13. The deletion in the S segment abrogates expression of the NSs protein, which is the major virulence factor of the virus. To develop a vaccine of even higher safety, a virus named R566 was created by natural laboratory reassortment. The R566 virus combines the S segment of the Clone 13 virus with additional attenuating mutations on the other two genome segments M and L, derived from the previously created MP-12 vaccine virus. To achieve the same objective, a nonspreading RVFV (NSR-Gn) was created by reverse-genetics, which not only lacks the NSs gene but also the complete M genome segment. We have now compared the vaccine efficacies of these two next-generation vaccines and included the Clone 13 vaccine as a control for optimal efficacy. Groups of eight lambs were vaccinated once and challenged three weeks later. All mock-vaccinated lambs developed high fever and viremia and three lambs did not survive the infection. As expected, lambs vaccinated with Clone 13 were protected from viremia and clinical signs. Two lambs vaccinated with R566 developed mild fever after challenge infection, which was associated with low levels of viral RNA in the blood, whereas vaccination with the NSR-Gn vaccine completely prevented viremia and clinical signs.

[Analysis of genetic structure and differentiation of the bog and dry land populations of Pinus sibirica du tour based on nuclear microsatellite loci].

We evaluated the population structure of the bog and dry land populations of the Siberian pine Pinus sibirica (P. sibrica) in Western Siberia using nuclear genome markers. Six pairs of nuclear microsatellite loci were used for this analysis. We detected 30 allelic variants in 120 individuals of four populations of P. Sibirica. We established that the studied populations differ by genetic structure. The most essential differences were identified between the Siberian pine population from oligotrophic bog and the group of populations from dry land within eutrophic bogs and near settlements P. sibirica forest (F(ST) = 0.019; D(N) = 0.053). We estimated that diversification of the West Siberian populations of P. sibirica exceeded 2.4% (F(ST) = 0.024), based on an analysis of SSR markers.

[Genetic diversity, population structure, and differentiation of Siberian larch, Gmelin larch and Cajander larch on SSR-markers data].

The genetic diversity of SSR markers was studied in six populations of Siberian larch, two populations of Gmelin larch, and four populations of Cajander larch. Seven pairs of nuclear microsatellite loci were used for this analysis. 103 allelic variants were detected in 365 individuals of three species of larch. According to the AMOVA results, the variability proportion that characterizes the differences between three Larix species was twice as higher (15%) than the proportion that accounts for among-population differences within the species (6%). The differentiation of the populations of three species of larch based on SSR markers exceeded 12% (FsT = 0.121). A significant correlation of the genetic distances with the geographic distances between populations was found (r = 0.835, P = 0.01).

Efficacy of three candidate Rift Valley fever vaccines in sheep.

Rift Valley fever virus (RVFV) is a mosquito-transmitted Bunyavirus that causes high morbidity and mortality among ruminants and humans. The virus is endemic to the African continent and the Arabian Peninsula and continues to spread into new areas. The explosive nature of RVF outbreaks requires that vaccines provide swift protection after a single vaccination. We recently developed several candidate vaccines and here report their efficacy in lambs within three weeks after a single vaccination. The first vaccine comprises the purified ectodomain of the Gn structural glycoprotein formulated in a water-in-oil adjuvant. The second vaccine is based on a Newcastle disease virus-based vector that produces both RVFV structural glycoproteins Gn and Gc. The third vaccine comprises a recently developed nonspreading RVFV. The latter two vaccines were administered without adjuvant. The inactivated whole virus-based vaccine produced by Onderstepoort Biological Products was used as a positive control. Five out of six mock-vaccinated lambs developed high viremia and fever and one lamb succumbed to the challenge infection. A single vaccination with each vaccine resulted in a neutralizing antibody response within three weeks after vaccination and protected lambs from viremia, pyrexia and mortality.

Surveillance on avian influenza in Bulgaria.

Nota de Investigacón Bulgaria has a surveillance program on avian influenza to keep a close watch on health of poultry, exotic birds, and wild birds. The samples include sera for serologic examination, and carcasses, tissue samples, tracheal and cloacal swabs, and feces for virologic examination. The number of samples depends on the epizootic situation in the country and in neighboring countries. Migration and resting and living areas of wild birds also are under consideration. The territory of Bulgaria is divided into 28 regions. For each of these regions, there are exact types and numbers of samples, depending on latitude, water reservoir, farms, and backyards. Since October 2005, surveillance has become harder because of the situation in Romania and Turkey. Since 2006, the number of samples has vastly increased.