Jiang, Xianhuan; Gao, Jun; Ni, Liju; Hu, Jianhua; Li, Kai; Sun, Fengping; Xie, Jianyun; Bo, Xiong; Gao, Chen; Xiao, Junhua; Zhou, Yuxun
Microtus fortis is a special resource of rodent in China. It is a promising experimental animal model for the study on the mechanism of Schistosome japonicum resistance. The first complete mitochondrial genome sequence for Microtus fortis calamorum, a subspecies of M. fortis (Arvicolinae, Rodentia), was reported in this study. The mitochondrial genome sequence of M. f. calamorum (Genbank: JF261175) showed a typical vertebrate pattern with 13 protein coding genes, 2 ribosomal RNAs, 22 transfer RNAs and one major noncoding region (CR region).The extended termination associated sequences (ETAS-1 and ETAS-2) and conserved sequence block 1 (CSB-1) were found in the CR region. The putative origin of replication for the light strand (O(L)) of M. f. calamorum was 35bp long and showed high conservation in stem and adjacent sequences, but the difference existed in the loop region among three species of genus Microtus. In order to investigate the phylogenetic position of M. f. calamorum, the phylogenetic trees (Maximum likelihood and Bayesian methods) were constructed based on 12 protein-coding genes (except for ND6 gene) on H strand from 16 rodent species. M. f. calamorum was classified into genus Microtus, Arvcicolinae for the highly phylogenetic relationship with Microtus kikuchii (Taiwan vole). Further phylogenetic analysis results based on the cytochrome b gene ranged from M. f. calamorum to one of the subspecies of M. fortis, which formed a sister group of Microtus middendorfii in the genus Microtus.
Full Text Available Abstract Background Mitochondrial and nuclear genes have generally been employed for different purposes in molecular systematics, the former to resolve relationships within recently evolved groups and the latter to investigate phylogenies at a deeper level. In the case of rapid and recent evolutionary radiations, mitochondrial genes like cytochrome b (CYB are often inefficient for resolving phylogenetic relationships. One of the best examples is illustrated by Arvicolinae rodents (Rodentia; Muridae, the most impressive mammalian radiation of the Northern Hemisphere which produced voles, lemmings and muskrats. Here, we compare the relative contribution of a nuclear marker – the exon 10 of the growth hormone receptor (GHR gene – to the one of the mitochondrial CYB for inferring phylogenetic relationships among the major lineages of arvicoline rodents. Results The analysis of GHR sequences improves the overall resolution of the Arvicolinae phylogeny. Our results show that the Caucasian long-clawed vole (Prometheomys schaposnikowi is one of the basalmost arvicolines, and confirm that true lemmings (Lemmus and collared lemmings (Dicrostonyx are not closely related as suggested by morphology. Red-backed voles (Myodini are found as the sister-group of a clade encompassing water vole (Arvicola, snow vole (Chionomys, and meadow voles (Microtus and allies. Within the latter, no support is recovered for the generic recognition of Blanfordimys, Lasiopodomys, Neodon, and Phaiomys as suggested by morphology. Comparisons of parameter estimates for branch lengths, base composition, among sites rate heterogeneity, and GTR relative substitution rates indicate that CYB sequences consistently exhibit more heterogeneity among codon positions than GHR. By analyzing the contribution of each codon position to node resolution, we show that the apparent higher efficiency of GHR is due to their third positions. Although we focus on speciation events spanning the last
Broadening diversity in the Arostrilepis horrida complex: Arostrilepis kontrimavichusi n. sp. (Cyclophyllidea: Hymenolepididae) in the western red-backed vole Myodes californicus (Merriam) (Cricetidae: Arvicolinae) from temperate latitudes of the Pacific Northwest, North America.
Makarikov, Arseny A; Hoberg, Eric P
Specimens originally identified provisionally as Hymenolepis horrida (Linstow, 1901) [later Arostrilepis horrida (Linstow, 1901)] in Myodes californicus (Merriam) from near the Pacific coastal zone of southern Oregon are revised. Specimens in western red-backed voles represent an undescribed species of Arostrilepis Mas Coma & Tenora, 1997, contributing to recognition and resolution of a broadening complex encompassing cryptic diversity for these hymenolepidid tapeworms distributed across the Holarctic region. Consistent with recent studies defining diversity in the genus, the form, dimensions, and spination (pattern, shape and size) of the cirrus are diagnostic. Among 12 nominal congeners, specimens of A. kontrimavichusi n. sp. are further distinguished by the relative position and length of the cirrus-sac, arrangement of the testes and relative size of the external seminal vesicle and seminal receptacle. Specimens from Oregon voles represent the fifth endemic hymenolepidid in this genus from the Nearctic. Host range for the North American assemblage of species includes Cricetidae (Arvicolinae and Neotominae), Heteromyidae, Geomyidae, and rarely Sciuridae. PMID:27221000
Bogićević, Katarina; Nenadić, Draženko; Mihailović, Dušan
Baranica is a cave system situated in the south-eastern part of Serbia, four kilometers south to Knjaževac, on the right bank of the Trgovi\\vski Timok. The investigations in Baranica were conducted from 1994 to 1997 by the Faculty of Philosophy from Belgrade and the National Museum of Knjaževac. Four geological layers of Quaternary age were recovered. The abundance of remains of both large and small mammals was noticed in the early phase of the research. In this paper, the remains of eight vole species are described: Arvicola terrestris (Linnaeus, 1758), Chionomys nivalis (Martins, 1842), Microtus (Microtus) arvalis (Pallas, 1778) and Microtus (Microtus) agrestis (Linnaeus, 1761), Microtus (Stenocranius) gregalis (Pallas, 1779), Microtus (Terricola) subterraneus (de Sélys-Longchamps, 1836), Clethrionomys glareolus (Schreber, 1780) and Lagurus lagurus (Pallas, 1773). Among them, steppe and open area inhabitants prevail. Based on the evolutionary level and dimensions of the Arvicola terrestris molars, as well as the overall characteristics of the fauna, it was concluded that the deposits were formed in the last glacial period of the Late Pleistocene. These conclusions are rather consistent with the absolute dating of large mammal bones (23.520 ± 110 B.P. for Layer 2 and 35.780 ± 320 B.P. for Layer 4).
[Genetic variation and phylogeography of the bank vole (Clethrionomys glareolus, Arvicolinae, Rodentia) in Russia with special reference to the introgression of the mtDNA of a closely related species, red-backed vole (C. rutilus)].
Abramson, N I; Rodchenkova, E N; Kostygov, A Iu
Totally, 294 bank voles (Clethrionomys glareolus) and 18 red-backed voles (C. rutilus) from 62 sites of European Russia were studied. Incomplete sequences (967 bp) of the mitochondrial cytochrome b gene were determined for 93 C. glareolus individuals from 56 sites and 18 C. rutilus individuals from the same habitats. Analysis of the cytochrome b gene variation has demonstrated that practically the entire European part of Russia, Ural, and a considerable part of Western Europe are inhabited by bank voles of the same phylogroup, displaying an extremely low genetic differentiation. Our data suggest that C. glareolus very rapidly colonized over the presently occupied territory in the post-Pleistocene period from no more than two (central European and western European) refugia for ancestral populations with a small efficient size. PCR typing of the mitochondrial cytochrome b gene allowed us to assess the scale of mtDNA introgression from a closely related species, C. rutilus, and to outline the geographical zone of this introgression. Comparison with the red-backed vole haplotypes in the habitats shared by both species favors the hypothesis of an ancient hybridization event (mid-Holocene) and a subsequent introgression. These results suggest that the hybridization took place in the southern and middle Pre-Ural region. PMID:19534420
Yanagihara, Richard; Gu, Se Hun; Arai, Satoru; Kang, Hae Ji; Song, Jin-Won
Virus and host gene phylogenies, indicating that antigenically distinct hantaviruses (family Bunyaviridae, genus Hantavirus) segregate into clades, which parallel the molecular evolution of rodents belonging to the Murinae, Arvicolinae, Neotominae and Sigmodontinae subfamilies, suggested co-divergence of hantaviruses and their rodent reservoirs. Lately, this concept has been vigorously contested in favor of preferential host switching and local host-specific adaptation. To gain insights into ...
Full Text Available Los hantavirus tienen huéspedes especie específicos pertenecientes a una familia común Muridae con tres sub familias, dos de ellas Murinae y Arvicolinae que se distribuyen en áreas geográficas de Europa Asia y Oceanía con un género Arvicolinae en América del Norte y la Sub familia Sigmodontinae en Centro América y Sudamérica. Estudios de la filogenia del huésped y el virus muestran fuertes similitudes al ser comparados, lo que sugiere una asociación de mucha más larga data con un proceso de coevolución entre el agente infeccioso y sus huéspedes roedores. La historia de la tierra y los procesos tectónicos y climáticos que afectaron al continente en épocas pretéritas son relevantes para comprender la actual distribución de los reservorios huéspedes y sus parásitos. Se entregan antecedentes biogeográficos de los roedores con la distribución geográfica de los hantavirus en Sudamérica, análisis filogenético de los virus, epidemiología molecular que sustentan la propuesta que el virus y el roedor han coevolucionado antes del momento de separarse la Familia Muridae en subfamilias (Murinae, Arvicolinae y Sigmodontinae y anterior al ingreso de los roedores sigmodontinos al continente sudamericano. Se discute la dificultad en demarcar especie nueva de hantavirus y la existencia de varios linajes con diferencias pequeñas entre si para ser consideradas como especies virales. Se describen diferencias y similitudes entre las dos especies de hantavirus que más casos han producido en América del Norte (virus Sin Nombre y en el Cono Sur de de América (Virus Andes.Hantavirus are associated with a single primary rodent host of the familiy Muridae in three sub families, two of them Murinae and Arvicolinae distributed in the Paleartic Region (Europa, Asia, China and the sub family Sigmodontinae in North, Central and South America besides an Arvicolinae genus (Microtus in North America. Studies on the host and virus phylogeny show
A. Vieira-Da-Silva; F. Adega; H. Guedes-Pinto; R. Chaves
L1 distribution in mammal’s genomes is yet a huge riddle. However, these repetitive sequences were already found in all chromosomic regions, and in general, they seem to be nonrandomly distributed in the genome. It also seems that after insertionand when they are not deleterious, they are always involved in dynamic processes occurring on that particular chromosomic region. Furthermore, it seems that large-scale genome rearrangements and L1 activity and accumulation are somehow interconnected. In the present study, we analysed L1 genomic distribution in Tatera gambiana (Muridae, Gerbillinae), Acomys sp. (Muridae, Deomyinae), Cricetomys sp. (Nesomyidae, Cricetomyinae), Microtus arvalis (Cricetidae, Arvicolinae), Phodopus roborovskii and P. sungorus (Cricetidae, Cricetinae). All the species studied here seems to exhibit a species-specific pattern.Possible mechanisms, and processes involved in L1 distribution and preferential accumulation in certain regions are discussed.
Full Text Available Abstract More than 20 years ago, hantaviral antigens were reported in tissues of the Eurasian common shrew (Sorex araneus, Eurasian water shrew (Neomys fodiens and common mole (Talpa europea, suggesting that insectivores, or soricomorphs, might serve as reservoirs of unique hantaviruses. Using RT-PCR, sequences of a genetically distinct hantavirus, designated Seewis virus (SWSV, were amplified from lung tissue of a Eurasian common shrew, captured in October 2006 in Graubünden, Switzerland. Pair-wise analysis of the full-length S and partial M and L segments of SWSV indicated approximately 55%–72% similarity with hantaviruses harbored by Murinae, Arvicolinae, Neotominae and Sigmodontinae rodents. Phylogenetically, SWSV grouped with other recently identified shrew-borne hantaviruses. Intensified efforts are underway to clarify the genetic diversity of SWSV throughout the geographic range of the Eurasian common shrew, as well as to determine its relevance to human health.
Fan, Longqing; Fan, Zhenxin; Yue, Hao; Zhang, Xiuyue; Liu, Yang; Sun, Zhiyu; Liu, Shaoying; Yue, Bisong
The Chinese scrub vole (Neodon irene) belongs to the subfamily Arvicolinae, which is restricted to mountain areas at high altitudes (2800-4000). In this study, we sequenced the complete mitochondrial genome of N. irene. It was determined to be 16,367 bases. The nucleotide sequence data of 12 heavy-strand protein-coding genes of N. irene and other 22 rodents were used for phylogenetic analysis. Bayesian inference (BI) and maximum likelihood (ML) were used. Both the BI and ML trees demonstrated that Microtus rossiaemeridionalis and Microtus kikuchii did not cluster together with each other. On the contrary, M. rossiaemeridionalis showed close relationship with N. irene. In the present study, only one sequence from Neodon and two sequences from Microtus were included in the phylogenetic analysis which should contribute to the unusual relationship. Therefore, in order to better understand the phylogenetic relationship within Rodentia, more rodents' complete mitochondrial genomes are required.
Song, Jin-Won; Kang, Hae Ji; Gu, Se Hun; Moon, Sung Sil; Bennett, Shannon N; Song, Ki-Joon; Baek, Luck Ju; Kim, Heung-Chul; O'Guinn, Monica L; Chong, Sung-Tae; Klein, Terry A; Yanagihara, Richard
Until recently, the single known exception to the rodent-hantavirus association was Thottapalayam virus (TPMV), a long-unclassified virus isolated from the Asian house shrew (Suncus murinus). Robust gene amplification techniques have now uncovered several genetically distinct hantaviruses from shrews in widely separated geographic regions. Here, we report the characterization of a newly identified hantavirus, designated Imjin virus (MJNV), isolated from the lung tissues of Ussuri white-toothed shrews of the species Crocidura lasiura (order Soricomorpha, family Soricidae, subfamily Crocidurinae) captured near the demilitarized zone in the Republic of Korea during 2004 and 2005. Seasonal trapping revealed the highest prevalence of MJNV infection during the autumn, with evidence of infected shrews' clustering in distinct foci. Also, marked male predominance among anti-MJNV immunoglobulin G antibody-positive Ussuri shrews was found, whereas the male-to-female ratio among seronegative Ussuri shrews was near 1. Plaque reduction neutralization tests showed no cross neutralization for MJNV and rodent-borne hantaviruses but one-way cross neutralization for MJNV and TPMV. The nucleotide and deduced amino acid sequences for the different MJNV genomic segments revealed nearly the same calculated distances from hantaviruses harbored by rodents in the subfamilies Murinae, Arvicolinae, Neotominae, and Sigmodontinae. Phylogenetic analyses of full-length S, M, and L segment sequences demonstrated that MJNV shared a common ancestry with TPMV and remained in a distinct out-group, suggesting early evolutionary divergence. Studies are in progress to determine if MJNV is pathogenic for humans.
Song, Jin-Won; Kang, Hae Ji; Gu, Se Hun; Moon, Sung Sil; Bennett, Shannon N.; Song, Ki-Joon; Baek, Luck Ju; Kim, Heung-Chul; O'Guinn, Monica L.; Chong, Sung-Tae; Klein, Terry A.; Yanagihara, Richard
Until recently, the single known exception to the rodent-hantavirus association was Thottapalayam virus (TPMV), a long-unclassified virus isolated from the Asian house shrew (Suncus murinus). Robust gene amplification techniques have now uncovered several genetically distinct hantaviruses from shrews in widely separated geographic regions. Here, we report the characterization of a newly identified hantavirus, designated Imjin virus (MJNV), isolated from the lung tissues of Ussuri white-toothed shrews of the species Crocidura lasiura (order Soricomorpha, family Soricidae, subfamily Crocidurinae) captured near the demilitarized zone in the Republic of Korea during 2004 and 2005. Seasonal trapping revealed the highest prevalence of MJNV infection during the autumn, with evidence of infected shrews' clustering in distinct foci. Also, marked male predominance among anti-MJNV immunoglobulin G antibody-positive Ussuri shrews was found, whereas the male-to-female ratio among seronegative Ussuri shrews was near 1. Plaque reduction neutralization tests showed no cross neutralization for MJNV and rodent-borne hantaviruses but one-way cross neutralization for MJNV and TPMV. The nucleotide and deduced amino acid sequences for the different MJNV genomic segments revealed nearly the same calculated distances from hantaviruses harbored by rodents in the subfamilies Murinae, Arvicolinae, Neotominae, and Sigmodontinae. Phylogenetic analyses of full-length S, M, and L segment sequences demonstrated that MJNV shared a common ancestry with TPMV and remained in a distinct out-group, suggesting early evolutionary divergence. Studies are in progress to determine if MJNV is pathogenic for humans. PMID:19357167
David R J Pleydell
Full Text Available BACKGROUND: Alveolar echinococcosis (AE presents a serious public health challenge within China. Mass screening ultrasound surveys can detect pre-symptomatic AE, but targeting areas identified from hospital records is inefficient regarding AE. Prediction of undetected or emerging hotspots would increase detection rates. Voles and lemmings of the subfamily Arvicolinae are important intermediate hosts in sylvatic transmission systems. Their populations reach high densities in productive grasslands where food and cover are abundant. Habitat availability is thought to affect arvicoline population dynamic patterns and definitive host-intermediate host interactions. Arvicoline habitat correlates with AE prevalence in Western Europe and southern Gansu Province, China. METHODS AND FINDINGS: Xiji County, Ningxia Hui Autonomous Region, borders southern Gansu. The aims of this study were to map AE prevalence across Xiji and test arvicoline habitat as a predictor. Land cover was mapped using remotely sensed (Landsat imagery. Infection status of 3,205 individuals screened in 2002-2003 was related, using generalised additive mixed models, to covariates: gender; farming; ethnicity; dog ownership; water source; and areal cover of mountain pasture and lowland pasture. A Markov random field modelled additional spatial variation and uncertainty. Mountain pasture and lowland pasture were associated with below and above average AE prevalence, respectively. CONCLUSIONS: Low values of the normalised difference vegetation index indicated sub-optimality of lowland pasture for grassland arvicolines. Unlike other known endemic areas, grassland arvicolines probably did not provide the principal reservoir for Echinococcus multilocularis in Xiji. This result is consistent with recent small mammal surveys reporting low arvicoline densities and high densities of hamsters, pikas and jerboas, all suitable intermediate hosts for E. multilocularis, in reforested lowland pasture
Full Text Available Abstract Background The fox tapeworm Echinococcus multilocularis has foxes and other canids as definitive host and rodents as intermediate hosts. However, most mammals can be accidental intermediate hosts and the larval stage may cause serious disease in humans. The parasite has never been detected in Sweden, Finland and mainland Norway. All three countries require currently an anthelminthic treatment for dogs and cats prior to entry in order to prevent introduction of the parasite. Documentation of freedom from E. multilocularis is necessary for justification of the present import requirements. Methods The probability that Sweden, Finland and mainland Norway were free from E. multilocularis and the sensitivity of the surveillance systems were estimated using scenario trees. Surveillance data from five animal species were included in the study: red fox (Vulpes vulpes, raccoon dog (Nyctereutes procyonoides, domestic pig, wild boar (Sus scrofa and voles and lemmings (Arvicolinae. Results The cumulative probability of freedom from EM in December 2009 was high in all three countries, 0.98 (95% CI 0.96-0.99 in Finland and 0.99 (0.97-0.995 in Sweden and 0.98 (0.95-0.99 in Norway. Conclusions Results from the model confirm that there is a high probability that in 2009 the countries were free from E. multilocularis. The sensitivity analyses showed that the choice of the design prevalences in different infected populations was influential. Therefore more knowledge on expected prevalences for E. multilocularis in infected populations of different species is desirable to reduce residual uncertainty of the results.