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P M Borodin - One of the best experts on this subject based on the ideXlab platform.
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chromosomal rearrangements do not seem to affect the gene flow in hybrid zones between karyotypic races of the common shrew sorex Araneus
Evolution, 2012Co-Authors: Agnes Horn, P M Borodin, P. Basset, Glenn Yannic, Agata Banaszek, Nina Bulatova, Katarzyna A Jadwiszczak, R M JonesAbstract:Chromosomal rearrangements are proposed to promote genetic differentiation between chromosomally differentiated taxa and therefore promote speciation. Due to their remarkable karyotypic polymorphism, the shrews of the Sorex Araneus group were used to investigate the impact of chromosomal rearrangements on gene flow. Five intraspecific chromosomal hybrid zones characterized by different levels of karyotypic complexity were studied using 16 microsatellites markers. We observed low levels of genetic differentiation even in the hybrid zones with the highest karyotypic complexity. No evidence of restricted gene flow between differently rearranged chromosomes was observed. Contrary to what was observed at the interspecific level, the effect of chromosomal rearrangements on gene flow was undetectable within the S. Araneus species.
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Telomeric DNA allocation in chromosomes of common shrew (Sorex Araneus, eulipotyphla)
Cell and Tissue Biology, 2009Co-Authors: N. S. Zhdanova, P M Borodin, Y. I. Rogozina, Y. M. Minina, N. B. RubtsovAbstract:Recently, we displayed an Iberian shrew species ( Sorex granarius ) with telomere structures unusual for mammals. Long telomeres on the short acrocentric arms contain an average of 213 kb of telomere repeats, whereas the other chromosomal ends have only 3.8 kb (Zhdanova et al., 2005; 2007). However, it is not clear whether these telomeres are typical for all shrew species or only for S. granarius. S. granarius and common shrew Sorex Araneus are sibling species. In this study, using modified Q-FISH we demonstrated that telomeres in S. Araneus from various chromosomal races distinguished by their number of metacentrics contain 6.8–15.2 kb of telomeric tracts. The S. Araneus telomere lengths appear to correspond to telomere lengths in the majority of both shrew species and wild mammals, whereas S. granarius has telomeres with unique or rare structures. Using DNA and RNA high-specific modified probes to telomeric repeats (PNA and LNA), we showed that interstitial telomeric sites in S. Araneus chromosomes contain mainly telomeric DNA and that their localization coincide with some evolutionary breakpoints. Interstitial telomeric DNA in S. granarius chromosomes was not revealed. Thus, the distribution of telomeric DNA may be significantly different, even in closely related species whose chromosomes are composed of almost identical chromosomal arms.
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Telomeric DNA allocation in chromosomes of common shrew Sorex Araneus, Eulipotyphla
Tsitologiia, 2009Co-Authors: N. S. Zhdanova, P M Borodin, Iu I Rogozina, Iu M Minina, N. B. RubtsovAbstract:Recently we have displayed shrew species, Iberian shrew S. granarius, with telomeres of unusual for mammals structure, including long telomeres on the short acrocentrics arms containing 213 kb on average and short telomeres (3.8 kb) on the other chromosomal ends (Zhdanova et al., 2005, 2007). However, it is not clear if such telomeres are characteristic of all shrew species or only of S. granarius. S. granarius and common shrew Sorex Araneus are the sibling species. In this investigation by using modified Q-FISH, we demonstrated that telomeres in S. Araneus from different chromosomal races differing in the numbers of metacentrics contain 6.8-15.2 kb of telomeric tracts. Thus, the S. Araneus telomere lengths appeared to correspond with telomere lengths both in shrews and majority wild mammalian species, and S. granarius has telomeres with unique or scarce structure. Furthermore, using DNA and RNA modified with probe high specificity to telomeric repeats (PNA and LNA) we showed that interstitial telomeric sites in S. Araneus chromosomes contained mainly telomeric DNA and their localization coincided with some evolutionary breakpoints. Interstitial telomeric DNA in S. granarius chromosomes was not revealed. Thus, distribution of telomeric DNA can greatly differ even in closely related species whose chromosomes are composed from almost identical chromosomal arms.
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the list of the chromosome races of the common shrew sorex Araneus updated 2002
Mammalia, 2003Co-Authors: Jan M Wojcik, Stanislaw Fedyk, J. Hausser, P M Borodin, Karl Fredga, Alina Mishta, V N OrlovAbstract:En suivant les principes de nomenclature des chromosomes de Sorex Araneus (Searle et al. 1991) et ceux de la definition de ses races chromosomiques (Hausser et al. 1994), l'ISACC (International Sorex Araneus Cytogenetics Committee) a publie en 1996 la premiere liste de races chromosomiques de S. Araneus (Zima et al., 1996). Elle comprenait 50 races chromosomiques. Depuis, 21 race nouvelles ont ete decrites et trois races ont ete eliminees de cette liste. Nous presentons ici la liste revisee des races chromosomiques de S. Araneus qui comprend actuellement 68 races.
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Chromosomal Evolution of the Common Shrew Sorex AraneusL. from the Southern Urals and Siberia in the Postglacial Period
Russian Journal of Genetics, 2001Co-Authors: A. V. Polyakov, V. V. Panov, T. Yu. Ladygina, M. N. Bochkarev, M. I. Rodionova, P M BorodinAbstract:This paper summarizes a series of studies on chromosomal geography of the common shrew Sorex Araneus L. in Siberia and the Southern Urals. Chromosomal races inhabiting the Southern Urals and the Western Siberian Plain sequentially replace each other in the latitudinal direction. In this region, karyotypes of each two adjacent races differ from each other by a single whole-arm reciprocal translocation. In the Eastern Siberian and Altai branches, the neighboring races differ mainly in the number or set of metacentric chromosomes. Analysis of the race distribution in the common shrew in the context of paleoecology of the glacial and postglacial period allowed us to reconstruct the sequence of events leading to the establishment of the present-day structure of the species S. Araneus .
N. S. Zhdanova - One of the best experts on this subject based on the ideXlab platform.
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Telomeric DNA allocation in chromosomes of common shrew (Sorex Araneus, eulipotyphla)
Cell and Tissue Biology, 2009Co-Authors: N. S. Zhdanova, P M Borodin, Y. I. Rogozina, Y. M. Minina, N. B. RubtsovAbstract:Recently, we displayed an Iberian shrew species ( Sorex granarius ) with telomere structures unusual for mammals. Long telomeres on the short acrocentric arms contain an average of 213 kb of telomere repeats, whereas the other chromosomal ends have only 3.8 kb (Zhdanova et al., 2005; 2007). However, it is not clear whether these telomeres are typical for all shrew species or only for S. granarius. S. granarius and common shrew Sorex Araneus are sibling species. In this study, using modified Q-FISH we demonstrated that telomeres in S. Araneus from various chromosomal races distinguished by their number of metacentrics contain 6.8–15.2 kb of telomeric tracts. The S. Araneus telomere lengths appear to correspond to telomere lengths in the majority of both shrew species and wild mammals, whereas S. granarius has telomeres with unique or rare structures. Using DNA and RNA high-specific modified probes to telomeric repeats (PNA and LNA), we showed that interstitial telomeric sites in S. Araneus chromosomes contain mainly telomeric DNA and that their localization coincide with some evolutionary breakpoints. Interstitial telomeric DNA in S. granarius chromosomes was not revealed. Thus, the distribution of telomeric DNA may be significantly different, even in closely related species whose chromosomes are composed of almost identical chromosomal arms.
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Telomeric DNA allocation in chromosomes of common shrew Sorex Araneus, Eulipotyphla
Tsitologiia, 2009Co-Authors: N. S. Zhdanova, P M Borodin, Iu I Rogozina, Iu M Minina, N. B. RubtsovAbstract:Recently we have displayed shrew species, Iberian shrew S. granarius, with telomeres of unusual for mammals structure, including long telomeres on the short acrocentrics arms containing 213 kb on average and short telomeres (3.8 kb) on the other chromosomal ends (Zhdanova et al., 2005, 2007). However, it is not clear if such telomeres are characteristic of all shrew species or only of S. granarius. S. granarius and common shrew Sorex Araneus are the sibling species. In this investigation by using modified Q-FISH, we demonstrated that telomeres in S. Araneus from different chromosomal races differing in the numbers of metacentrics contain 6.8-15.2 kb of telomeric tracts. Thus, the S. Araneus telomere lengths appeared to correspond with telomere lengths both in shrews and majority wild mammalian species, and S. granarius has telomeres with unique or scarce structure. Furthermore, using DNA and RNA modified with probe high specificity to telomeric repeats (PNA and LNA) we showed that interstitial telomeric sites in S. Araneus chromosomes contained mainly telomeric DNA and their localization coincided with some evolutionary breakpoints. Interstitial telomeric DNA in S. granarius chromosomes was not revealed. Thus, distribution of telomeric DNA can greatly differ even in closely related species whose chromosomes are composed from almost identical chromosomal arms.
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unusual distribution pattern of telomeric repeats in the shrews sorex Araneus and sorex granarius
Chromosome Research, 2005Co-Authors: N. S. Zhdanova, T V Karamisheva, J M Minina, Natalia M Astakhova, Peter M Lansdorp, Makoto Kammori, Nikolai Rubtsov, Jeremy B SearleAbstract:Sorex Araneus and Sorex granarius are sibling species within the Sorex Araneus group with karyotypes composed of almost identical chromosome arms. S. granarius has a largely acrocentric karyotype, while, in S. Araneus, various of these acrocentrics have combined together by Robertsonian (Rb) fusions to form metacentrics, with the numbers and types of metacentrics differing between chromosomal races. Our studies on telomeric sequences in S. Araneus and S. granarius revealed differences between chromosomes and between species. In S. Araneus (the Novosibirsk race), hybridization signals were present on the telomeres of all the chromosomes after FISH with a PCR-generated telomeric probe. In addition, hybridization signals were observed at high frequencies in the pericentric regions of some but not all metacentrics formed by Rb fusion. There were fewer signals on those metacentrics formed earlier in the evolution of S. Araneus. This suggests that S. Araneus chromosomes retain at least some telomeric repeats during Rb fusion, but that these repeats are lost or modified over time. These results are critical for the interpretation of the well-studied hybrid zones between chromosomal races of S. Araneus, given that Rb fission has been postulated in such hybrid zones and that the likelihood of Rb fission will relate to presence/absence of telomeric sequences at the centromeres of metacentrics. In S. granarius, there were strong signals at the proximal (centromeric) telomeres of the acrocentrics after FISH with a DNA telomeric probe. FISH with a PNA telomeric probe on S. granarius acrocentrics showed that the proximal telomeres were 213 kb on average, while the length of the distal telomeres was 3.8 kb on average. Two-colour FISH, using a telomeric DNA probe and a microdissected probe generated from the pericentric regions of the S. granarius chromosomes a and b, revealed regions on distinct chromatin fibres where telomeric and microdissected probes were colocalized or localized sequentially. The proximal telomeres of S. granarius are highly unusual both in their large size and their heterogeneous structure relative to the telomeres of other mammals.
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Current cytogenetic map of the common shrew, Sorex Araneus L.: localization of 7 genes and 4 microsatellites
Mammalia, 2003Co-Authors: N. S. Zhdanova, Valentina M. Fokina, Francois Balloux, J. Hausser, Pavel M. Borodin, V. Volobouev, O. L. Serov, D. M. LarkinAbstract:Les donnees sur la localisation de sept genes, ACADVL, ADORA 3 , ATP7A, MTMR4, MYH2, HBB, TSPAN-3 et quatre microsatellites sur les chromosomes de la musaraigne commune Sorex Araneus sont presentees, ainsi que l'etat actuel de la cartographie cytogenetique chez cette espece. La comparaison des donnees disponibles sur la cartographie de S. Araneus et de l'homme a permis de suggerer la sequence des remaniements chromosomiques survenus depuis la divergence des Insectivores et des Primates sur le tronc commun des Mammiferes.
Leszek Rychlik - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of the physiological activity of venom from the Eurasian water shrew Neomys fodiens
Frontiers in Zoology, 2017Co-Authors: Krzysztof Kowalski, Paweł Marciniak, Grzegorz Rosiński, Leszek RychlikAbstract:Background Animal toxins can have medical and therapeutic applications. Principally, toxins produced by insects, arachnids, snakes and frogs have been characterized. Venomous mammals are rare, and their venoms have not been comprehensively investigated. Among shrews, only the venom of Blarina brevicauda has been analysed so far, and blarina toxin has been proven to be its main toxic component. It is assumed that Neomys fodiens employs its venom to hunt larger prey. However, the toxic profile, properties and mode of action of its venom are largely unknown. Therefore, we analysed the cardio-, myo- and neurotropic properties of N. fodiens venom and saliva of non-venomous Sorex Araneus (control tests) in vitro in physiological bioassays carried out on two model organisms: beetles and frogs. For the first time, we fractionated N. fodiens venom and S. Araneus saliva by performing chromatographic separation. Next, the properties of selected compounds were analysed in cardiotropic bioassays in the Tenebrio molitor heart. Results The venom of N. fodiens caused a high decrease in the conduction velocity of the frog sciatic nerve, as well as a significant decrease in the force of frog calf muscle contraction. We also recorded a significant decrease in the frog heart contractile activity. Most of the selected compounds from N. fodiens venom displayed a positive chronotropic effect on the beetle heart. However, one fraction caused a strong decrease in the T. molitor heart contractile activity coupled with a reversible cardiac arrest. We did not observe any responses of the insect heart and frog organs to the saliva of S. Araneus . Preliminary mass spectrometry analysis revealed that calmodulin-like protein, thymosin β-10, hyaluronidase, lysozyme C and phospholipase A2 are present in the venom of N. fodiens , whereas thymosin β4, lysozyme C and β-defensin are present in S. Araneus saliva. Conclusion Our results showed that N. fodiens venom has stronger paralytic properties and lower cardioinhibitory activity. Therefore, it is highly probable that N. fodiens might use its venom as a prey immobilizing agent. We also confirmed that S. Araneus is not a venomous mammal because its saliva did not exhibit any toxic effects.
Magnus Lucassen - One of the best experts on this subject based on the ideXlab platform.
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Characterization and analysis of a transcriptome from the boreal spider crab Hyas Araneus.
Comparative biochemistry and physiology. Part D Genomics & proteomics, 2013Co-Authors: Lars Harms, Stephan Frickenhaus, Melanie Schiffer, Felix Christopher Mark, Daniela Storch, Hans-otto Pörtner, Christoph Held, Magnus LucassenAbstract:Research investigating the genetic basis of physiological responses has significantly broadened our understanding of the mechanisms underlying organismic response to environmental change. However, genomic data are currently available for few taxa only, thus excluding physiological model species from this approach. In this study we report the transcriptome of the model organism Hyas Araneus from Spitsbergen (Arctic). We generated 20,479 transcripts, using the 454 GS FLX sequencing technology in combination with an Illumina HiSeq sequencing approach. Annotation by Blastx revealed 7159 blast hits in the NCBI non-redundant protein database. The comparison between the spider crab H. Araneus transcriptome and EST libraries of the European lobster Homarus americanus and the porcelain crab Petrolisthes cinctipes yielded 3229/2581 sequences with a significant hit, respectively. The clustering by the Markov Clustering Algorithm (MCL) revealed a common core of 1710 clusters present in all three species and 5903 unique clusters for H. Araneus. The combined sequencing approaches generated transcripts that will greatly expand the limited genomic data available for crustaceans. We introduce the MCL clustering for transcriptome comparisons as a simple approach to estimate similarities between transcriptomic libraries of different size and quality and to analyze homologies within the selected group of species. In particular, we identified a large variety of reverse transcriptase (RT) sequences not only in the H. Araneus transcriptome and other decapod crustaceans, but also sea urchin, supporting the hypothesis of a heritable, anti-viral immunity and the proposed viral fragment integration by host-derived RTs in marine invertebrates.
Jacques Hausser - One of the best experts on this subject based on the ideXlab platform.
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Study of Gene Flow Through a Hybrid Zone in the Common Shrew (Sorex Araneus) Using Microsatellites
Hereditas, 2004Co-Authors: Nicolas Lugon Moulin, Andreas Wyttenbach, Harald Brüunner, Jérôme Goudet, Jacques HausserAbstract:The common shrew (Sorex Araneus) is subdivided into several chromosomal races. As hybrid zones between them have been characterized, this organism is of particular interest in studying the role of chromosomes in speciation. Six microsatellite loci were used to evaluate the level of gene flow in the S. Araneus hybrid zone between the Cordon and Valais races. Most of these loci were very polymorphic, the total number of alleles detected per locus ranging from 3 to 20. Using Mantel tests, we showed that the effect of rivers as barriers to gene flow is less important at this sampling scale. The effect of the chromosomal race is of particular importantance in diminishing gene flow.
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a taxonomical re evaluation of the valais chromosome race of the common shrew sorex Araneus insectivora soricidae
Acta Theriologica, 2002Co-Authors: Harald Brünner, Francois Balloux, Luca Fumagalli, Nicolas Lugonmoulin, Jacques HausserAbstract:The common shrewSorex Araneus Linnaeus, 1758 is subject to intense chromosomal polymorphism. About 65 chromosome races are presently known. One of these chromosome races (the Valais race) is karyologically, morphologically, biochemically, and genetically clearly distinct from all other chromosome races of the species. Recent studies of hybrid zones between the Valais race and other chromosome races in the Swiss and French Alps add further strong evidence for the specific taxonomic status of the Valais race. Chromosomes and diagnostic protein markers reveal sharp frequency clines and strong heterozygote deficits. In one hybrid zone, the maintenance of the strong genetic differentiation of the hybridizing taxa was confirmed by a study with autosomal microsatellites indicating minimal gene flow. A microsatellite marker on the Y-chromosome showed complete absence of male mediated gene flow suggesting hybrid male sterility. To clarify the taxonomic status of this taxon, additional analyses were conducted. A morphometric analysis of the mandible indicated the Valais race is morphologically as distinct from neighbouring chromosome races ofS. Araneus as from other relatedSorex species. In a phylogeny based on complete mitochondrial DNA cytochromeb gene sequences, the Valais race clearly appears as the sister taxon to all other races ofS. Araneus. Therefore, the chromosome race Valais ofS. Araneus herein is elevated to specific status and the nameSorex antinorii Bonaparte, 1840 is applied.
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A taxonomical re-evaluation of the Valais chromosome race of the common shrewSorex Araneus (Insectivora: Soricidae)
Acta Theriologica, 2002Co-Authors: Harald Brünner, Francois Balloux, Luca Fumagalli, Nicolas Lugon-moulin, Jacques HausserAbstract:The common shrew Sorex Araneus Linnaeus, 1758 is subject to intense chromosomal polymorphism. About 65 chromosome races are presently known. One of these chromosome races (the Valais race) is karyologically, morphologically, biochemically, and genetically clearly distinct from all other chromosome races of the species. Recent studies of hybrid zones between the Valais race and other chromosome races in the Swiss and French Alps add further strong evidence for the specific taxonomic status of the Valais race. Chromosomes and diagnostic protein markers reveal sharp frequency clines and strong heterozygote deficits. In one hybrid zone, the maintenance of the strong genetic differentiation of the hybridizing taxa was confirmed by a study with autosomal microsatellites indicating minimal gene flow. A microsatellite marker on the Y-chromosome showed complete absence of male mediated gene flow suggesting hybrid male sterility. To clarify the taxonomic status of this taxon, additional analyses were conducted. A morphometric analysis of the mandible indicated the Valais race is morphologically as distinct from neighbouring chromosome races of S. Araneus as from other related Sorex species. In a phylogeny based on complete mitochondrial DNA cytochrome b gene sequences, the Valais race clearly appears as the sister taxon to all other races of S. Araneus . Therefore, the chromosome race Valais of S. Araneus herein is elevated to specific status and the name Sorex antinorii Bonaparte, 1840 is applied.
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chromosomal versus mitochondrial dna evolution tracking the evolutionary history of the southwestern european populations of the sorex Araneus group mammalia insectivora
Evolution, 1994Co-Authors: Pierre Taberlet, Luca Fumagalli, Jacques HausserAbstract:: The shrews of the Sorex Araneus group have undergone a spectacular chromosome evolution. The karyotype of Sorex granarius is generally considered ancestral to those of Sorex coronatus and S. Araneus. However, a sequence of 777 base pairs of the cytochrome b gene of the mitochondrial DNA (mtDNA) produces a quite different picture: S. granarius is closely related to the populations of S. Araneus from the Pyrenees and from the northwestern Alps, whereas S. coronatus and S. Araneus from Italy and the southern Alps represent two well-separated lineages. It is suggested that mtDNA and chromosomal evolution are in this case largely independant processes. Whereas mtDNA haplotypes are closely linked to the geographical history of the populations, chromosomal mutations were probably transmitted from one population to another. Available data suggest that the impressive chromosome polymorphism of this group is quite a recent phenomenon.