The phylogeography of four Apodemus species (Apodemus agrarius, Apodemus peninsulae, Apodemus latronum, and Apodemus draco) was studied in the Far East of Asia, based on sequences of the mitochondrial DNA cytochrome b gene. The results obtained show the existence of many different genetic lineages within the studied Apodemus species, suggesting the isolation and differentiation of populations in multiple refuge areas. Higher genetic diversities in some regions such as Yunnan, Sichuan (China), and eastern Russia suggest these areas are potential refuges for these species. The existence of such complex genetic structures could be linked to the presence of many biogeographic barriers (Himalaya Mountains, Tien-shan Mountains, Altai Mountains, Tibetan Plateau, Gobi desert, Yunnan Guizhou Plateau, Dzungaria basin, and others) in these regions, which were probably reinforced during the Quaternary climate changes. These barriers also played an important role concerning the low dispersal abilities of the two studied Apodemus species adapted to forest habitats (A. latronum and A. draco) with respect to colonizing regions other than China.

Sequences of the mitochondrial cyt b gene and nuclear IRBP, RAGI, 17, and vWF genes were used to assess the evolutionary history of major lineages of Apodemus, in particular to better understand dispersal between Asia and Europe. Our data show eight extant lineages of Late Tertiary origin: Apodemus agrarius, A. semotus, A. peninsulae, A. speciosus, A. argenteus, A. gurkha, A. mystacinus, and A. sylvaticus. Monophyly of two European lineages (A. mystacinus and A. sylvaticus) and four Asian lineages (A. agrarius, A. semotus, A. peninsulae, and A. speciosus) was confirmed with high bootstrap support. Together with literature data, the available molecular data depict three crucial evolutionary events: (1) initial wide dispersal and subsequent radiation around 6 million years ago, (2) region-specific radiations in Europe and southern China around 2 million years ago, and (3) westward dispersal of A. agrarius to Europe in the Late Quaternary.

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a b s t r a c tBecause size reduced, or bottlenecked, populations are more prone to adverse events, the detection of genetic bottleneck signatures in wildlife species is highly relevant for conservation. Here we applied 11 microsatellite markers to the endangered Siberian tiger (Panthera tigris altaica) using tissue and blood samples of animals from the Primorsky region of the Russian Far East. Excess heterozygosity and mode shift in allele frequencies tests were positive, while the M-ratio test was negative, indicating the likelihood of a contemporary rather than a historical population bottleneck. The recent genetic population bottleneck could be attributed to the well-documented demographic collapse of the Siberian tiger population in the 1940s, when population size hit bottom with 20-30 surviving animals. The mean effective population size N e was 14 Siberian tigers (CI 95 : 12-25 animals), and the effective population size/census size ratio (N e /N ratio) was 0.028. This is the first molecular evidence of a recent Siberian tiger population bottleneck, which is of great interest for further conservation and management plans of the highly endangered largest felid species, while the worryingly low effective population size challenges the optimism for the recovery of the huge Siberian cat.

To better understand the evolutionary history of oriental wildlife newcomers in Europe, we studied the phylogeography and demographic history of the striped field mouse, Apodemus agrarius, throughout its Palaearctic distribution area. Genetic datasets including cytochrome b gene sequences and microsatellite markers were analysed using a large range of population genetics methodologies, including coalescent models and approximate Bayesian computations. Our results showed high mitochondrial genetic homogeneity among A. agrarius populations throughout the Palaearctic region, but microsatellite markers detected a finer population structure with the genetic differentiation of populations from the Eastern and Western distribution ranges. The Western colonisation likely originated from Far East Russian populations during one of the last interglacials. After their colonisation of the Central Asia and Western regions, the Central Palaearctic populations became isolated from their Eastern relatives. Our coalescent-based approaches suggested a separation between these two distribution ranges around 38 kya or more recently (around 11 kya). Limited gene flow still happened between populations in the two main distribution ranges, mainly from the Eastern to Western populations. Our study, for the first time, provides an overview of the evolutionary and demographic history of the striped field mouse throughout the Palaearctic region. A. agrarius appears to be an Asiatic immigrant and a relatively new member of the European fauna community. This study further confirms the important role of Far East Asian regions as a source of European biodiversity.

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BackgroundWild ginseng, Panax ginseng Meyer, is an endangered species of medicinal plants. In the present study, we analyzed variations within the ribosomal DNA (rDNA) cluster to gain insight into the genetic diversity of the Oriental ginseng, P. ginseng, at artificial plant cultivation.MethodsThe roots of wild P. ginseng plants were sampled from a nonprotected natural population of the Russian Far East. The slides were prepared from leaf tissues using the squash technique for cytogenetic analysis. The 18S rDNA sequences were cloned and sequenced. The distribution of nucleotide diversity, recombination events, and interspecific phylogenies for the total 18S rDNA sequence data set was also examined.ResultsIn mesophyll cells, mononucleolar nuclei were estimated to be dominant (75.7%), while the remaining nuclei contained two to four nucleoli. Among the analyzed 18S rDNA clones, 20% were identical to the 18S rDNA sequence of P. ginseng from Japan, and other clones differed in one to six substitutions. The nucleotide polymorphism was more expressed at the positions 440–640 bp, and distributed in variable regions, expansion segments, and conservative elements of core structure. The phylogenetic analysis confirmed conspecificity of ginseng plants cultivated in different regions, with two fixed mutations between P. ginseng and other species.ConclusionThis study identified the evidences of the intragenomic nucleotide polymorphism in the 18S rDNA sequences of P. ginseng. These data suggest that, in cultivated plants, the observed genome instability may influence the synthesis of biologically active compounds, which are widely used in traditional medicine.

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