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Evgeniy S Balakirev - One of the best experts on this subject based on the ideXlab platform.
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Mitochondrial DNA Variation and Introgression in Siberian Taimen Hucho taimen
2016Co-Authors: Evgeniy S Balakirev, Nikolai S Romanov, Pavel B Mikheev, Francisco J AyalaAbstract:Siberian taimen Hucho taimen is the largest representative of the family Salmonidae inhabiting rivers of northern Eurasia. The species is under intensive aquaculture activity. To monitor natural taimen populations we have sequenced a portion (8,141 bp) of the mitochondrial (mt) genome in 28 specimens of H. taimen from six localities in the Amur River basin. Nucleotide variability is low (p = 0.0010), but structured in two divergent haplotype groups. A comparison of the data with the GenBank H. taimenmt genome (HQ897271) reveals significant differences between them in spite of the fact that the fish specimens come from neighboring geographical areas. The distribution of divergence is non-uniform with two highly pronounced divergent regions centered on two genes, ND3 and ND6. To clarify the pattern of divergence we sequenced the corresponding portion of the mt genome of lenok Brachymystax tumensis and analyzed the GenBank complete mt genomes of related species. We have found that the first and second divergent regions are identical between the GenBank H. taimen and two lenok subspecies, B. lenok and B. lenok tsinlingensis, respectively. Consequently, both divergent regions represent introgressed mtDNA resulting from Intergeneric Hybridization between the two lenok subspecies and H. taimen. Introgression is, however, not detected in our specimens. This plus the precise identity of the introgressed fragments between the donor and the recipient GenBank sequence suggests that the introgression is local and very recent, probably due to artificial manipulations involving taimen – lenok Intergeneric Hybridization. Human-mediated Hybridization ma
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mitochondrial dna variation and introgression in siberian taimen hucho taimen
PLOS ONE, 2013Co-Authors: Evgeniy S Balakirev, Nikolai S Romanov, Pavel B Mikheev, Francisco J AyalaAbstract:Siberian taimen Hucho taimen is the largest representative of the family Salmonidae inhabiting rivers of northern Eurasia. The species is under intensive aquaculture activity. To monitor natural taimen populations we have sequenced a portion (8,141 bp) of the mitochondrial (mt) genome in 28 specimens of H. taimen from six localities in the Amur River basin. Nucleotide variability is low (p=0.0010), but structured in two divergent haplotype groups. A comparison of the data with the GenBank H. taimen mt genome (HQ897271) reveals significant differences between them in spite of the fact that the fish specimens come from neighboring geographical areas. The distribution of divergence is non-uniform with two highly pronounced divergent regions centered on two genes, ND3 and ND6. To clarify the pattern of divergence we sequenced the corresponding portion of the mt genome of lenok Brachymystax tumensis and analyzed the GenBank complete mt genomes of related species. We have found that the first and second divergent regions are identical between the GenBank H. taimen and two lenok subspecies, B. lenok and B. lenok tsinlingensis, respectively. Consequently, both divergent regions represent introgressed mtDNA resulting from Intergeneric Hybridization between the two lenok subspecies and H. taimen. Introgression is, however, not detected in our specimens. This plus the precise identity of the introgressed fragments between the donor and the recipient GenBank sequence suggests that the introgression is local and very recent, probably due to artificial manipulations involving taimen – lenok Intergeneric Hybridization. Human-mediated Hybridization may become a major threat to aquatic biodiversity. Consequently we suggest that due attention needs to be given to this threat by means of responsible breeding program management, so as to prevent a potential spread of hybrid fishes that could jeopardize the resilience of locally adapted gene pools of the native H. taimen populations.
Francisco J Ayala - One of the best experts on this subject based on the ideXlab platform.
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Mitochondrial DNA Variation and Introgression in Siberian Taimen Hucho taimen
2016Co-Authors: Evgeniy S Balakirev, Nikolai S Romanov, Pavel B Mikheev, Francisco J AyalaAbstract:Siberian taimen Hucho taimen is the largest representative of the family Salmonidae inhabiting rivers of northern Eurasia. The species is under intensive aquaculture activity. To monitor natural taimen populations we have sequenced a portion (8,141 bp) of the mitochondrial (mt) genome in 28 specimens of H. taimen from six localities in the Amur River basin. Nucleotide variability is low (p = 0.0010), but structured in two divergent haplotype groups. A comparison of the data with the GenBank H. taimenmt genome (HQ897271) reveals significant differences between them in spite of the fact that the fish specimens come from neighboring geographical areas. The distribution of divergence is non-uniform with two highly pronounced divergent regions centered on two genes, ND3 and ND6. To clarify the pattern of divergence we sequenced the corresponding portion of the mt genome of lenok Brachymystax tumensis and analyzed the GenBank complete mt genomes of related species. We have found that the first and second divergent regions are identical between the GenBank H. taimen and two lenok subspecies, B. lenok and B. lenok tsinlingensis, respectively. Consequently, both divergent regions represent introgressed mtDNA resulting from Intergeneric Hybridization between the two lenok subspecies and H. taimen. Introgression is, however, not detected in our specimens. This plus the precise identity of the introgressed fragments between the donor and the recipient GenBank sequence suggests that the introgression is local and very recent, probably due to artificial manipulations involving taimen – lenok Intergeneric Hybridization. Human-mediated Hybridization ma
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mitochondrial dna variation and introgression in siberian taimen hucho taimen
PLOS ONE, 2013Co-Authors: Evgeniy S Balakirev, Nikolai S Romanov, Pavel B Mikheev, Francisco J AyalaAbstract:Siberian taimen Hucho taimen is the largest representative of the family Salmonidae inhabiting rivers of northern Eurasia. The species is under intensive aquaculture activity. To monitor natural taimen populations we have sequenced a portion (8,141 bp) of the mitochondrial (mt) genome in 28 specimens of H. taimen from six localities in the Amur River basin. Nucleotide variability is low (p=0.0010), but structured in two divergent haplotype groups. A comparison of the data with the GenBank H. taimen mt genome (HQ897271) reveals significant differences between them in spite of the fact that the fish specimens come from neighboring geographical areas. The distribution of divergence is non-uniform with two highly pronounced divergent regions centered on two genes, ND3 and ND6. To clarify the pattern of divergence we sequenced the corresponding portion of the mt genome of lenok Brachymystax tumensis and analyzed the GenBank complete mt genomes of related species. We have found that the first and second divergent regions are identical between the GenBank H. taimen and two lenok subspecies, B. lenok and B. lenok tsinlingensis, respectively. Consequently, both divergent regions represent introgressed mtDNA resulting from Intergeneric Hybridization between the two lenok subspecies and H. taimen. Introgression is, however, not detected in our specimens. This plus the precise identity of the introgressed fragments between the donor and the recipient GenBank sequence suggests that the introgression is local and very recent, probably due to artificial manipulations involving taimen – lenok Intergeneric Hybridization. Human-mediated Hybridization may become a major threat to aquatic biodiversity. Consequently we suggest that due attention needs to be given to this threat by means of responsible breeding program management, so as to prevent a potential spread of hybrid fishes that could jeopardize the resilience of locally adapted gene pools of the native H. taimen populations.
Masaru Nakano - One of the best experts on this subject based on the ideXlab platform.
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Intergeneric Hybridization among colchicaceous ornamentals, Gloriosa spp., Littonia modesta and Sandersonia aurantiaca via ovule culture
Plant Biotechnology, 2009Co-Authors: Junji Amano, Daisuke Nakazawa, Sachiko Kuwayama, Yoko Mizuta, Hajime Okuno, Yusuke Watanabe, Toshinari Godo, Dong-sheng Han, Masaru NakanoAbstract:Colchicaceous plants, Gloriosa spp., Littonia modesta and Sandersonia aurantiaca, are cultivated as ornamentals. However, unfortunately no large variations in horticultural traits are found within each genus. We examined Intergeneric Hybridization using 6 genotypes of Gloriosa spp., 1 genotype of L. modesta and 2 genotypes of S. aurantiaca to obtain wider variability and to develop novel cultivars in those groups. Following Intergeneric cross-pollination, putative hybrid plantlets were obtained via ovule culture in various combinations. Early confirmation of the hybridity of ovule culture-derived plantlets was accomplished by flow cytometry and random amplified polymorphic DNA analyses. Several Intergeneric hybrids have so far been produced flowers and subjected to morphological characterization. All the hybrids examined, i.e. L. modesta×S. aurantiaca, L. modesta×S. aurantiaca ‘Phoenix’, L. modesta×G. superba ‘Lutea’, L. modesta×G. ‘Marron Gold’, S. aurantiaca×G. superba ‘Lutea’, S. aurantiaca×G. ‘Marron Gold’ and S. aurantiaca ‘Phoenix’×G. ‘Marron Gold’, had novel morphological characteristics compared with their parents, some of which were horticulturally attractive. The results obtained in our series of studies indicate the validity of Intergeneric Hybridization in the improvement programs of colchicaceous ornamentals. We are now examining to develop a rapid and efficient micropropagation system and to restore fertility by artificial chromosome doubling of Intergeneric hybrids that had been produced in our series of experiments.
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cross compatibility in interspecific and Intergeneric Hybridization among the colchicaceous ornamentals gloriosa spp littonia modesta and sandersonia aurantiaca
Acta Horticulturae, 2005Co-Authors: Sachiko Kuwayama, Masaru Nakano, Yoko Mizuta, T Nakamura, T OomiyaAbstract:Interspecific and Intergeneric cross-pollination and subsequent ovule culture were carried out among 6 genotypes of Gloriosa spp., 1 genotype of L. modesta and 2 genotypes of S. aurantiaca in order to widen their variations and to develop novel cultivars. Ovules with placental tissues prepared from ovaries 14 days after pollination were cultured at 25°C in the dark on a medium containing 0.01 mg l -1 α α α α -naphthaleneacetic acid (NAA) and 0.01 mg l -1 benzyladenine (BA), on which rhizome-like structures were produced from the ovules in 49 out of 61 cross-combinations. Following transfer to a medium containing 0.25 mg l -1 NAA and 2.5 mg l -1 BA under a 16-h photoperiod, some of the rhizome-like structures produced shoots and/or root-like structures. These shoots developed into plantlets and produced tubers on a plant growth regulator-free medium. In some of the plantlets derived from Intergeneric cross-pollination, early confirmation of the hybridity was accomplished by flow cytometry analysis of relative DNA content of nuclei.
B A Levin - One of the best experts on this subject based on the ideXlab platform.
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phylogeny phylogeography and Hybridization of caucasian barbels of the genus barbus actinopterygii cyprinidae
Molecular Phylogenetics and Evolution, 2019Co-Authors: B A Levin, Alexander A Gandlin, Evgeniy S Simonov, M A Levina, Anna E Barmintseva, Bella Japoshvili, N S Mugue, Levan Mumladze, Namig J MustafayevAbstract:Abstract Phylogenetic relationships and phylogeography of six species of Caucasian barbels, the genus Barbus s. str., were studied based on extended geographic coverage and using mtDNA and nDNA markers. Based on 27 species studied, matrilineal phylogeny of the genus Barbus is composed of two clades – (a) West European clade, (b) Central and East European clade. The latter comprises two subclades: (b1) Balkanian subclade, and (b2) Ponto-Caspian one that includes 11 lineages mainly from Black and Caspian Sea drainages. Caucasian barbels are not monophyletic and subdivided for two groups. The Black Sea group encompasses species from tributaries of Black Sea including re-erected B. rionicus and excluding B. kubanicus. The Caspian group includes B. ciscaucasicus, B. cyri (with B. goktschaicus that might be synonymized with B. cyri), B. lacerta from the Tigris-Euphrates basin and B. kubanicus from the Kuban basin. Genetic structure of Black Sea barbels was influenced by glaciation-deglaciation periods accompanying by freshwater phases, periods of migration and colonization of Black Sea tributaries. Intra- and Intergeneric Hybridization among Caucasian barbines was revealed. In the present study, we report about finding of B. tauricus in the Kuban basin, where only B. kubanicus was thought to inhabit. Hybrids between these species were detected based on both mtDNA and nDNA markers. Remarkably, Kuban population of B. tauricus is distant to closely located conspecific populations and we consider it as relic. We highlight revealing the Intergeneric Hybridization between evolutionary tetraploid (2n = 100) B. goktschaicus and evolutionary hexaploid (2n = 150) Capoeta sevangi in Lake Sevan.
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phylogeny phylogeography and Hybridization of caucasian barbels of the genus barbus actinopterygii cyprinidae
bioRxiv, 2018Co-Authors: B A Levin, Alexander A Gandlin, Evgeniy S Simonov, M A Levina, Anna E Barmintseva, Bella Japoshvili, N S Mugue, Levan Mumladze, Namig J MustafayevAbstract:The phylogenetic relationships and the phylogeography of seven species of Caucasian barbels of the genus Barbus s. str. were studied based on extended geographic coverage and the use of mtDNA and nDNA markers. Based on the 26 species studied, matrilineal phylogeny of the genus Barbus is composed of two clades: a) West European clade, and b) Central and East European clade. The latter comprises two subclades: b1) Balkanian subclade, and b2) Ponto-Caspian subclade, which includes 11 lineages mainly from Black and Caspian Sea drainages. Caucasian barbels are not monophyletic and are subdivided into two groups. The Black Sea group encompasses species from tributaries of the Black Sea, including the reinstalled B. rionicus , except for B. kubanicus . The Caspian group includes B. ciscaucasicus , B. cyri (with B. goktschaicus , which might be synonymized with B. cyri ), B. lacerta from the Tigris-Euphrates basin and B. kubanicus from the Kuban basin. The genetic structure of Black Sea barbels was influenced by glaciation-deglaciation periods accompanied by freshwater phases, periods of migration and the colonization of Black Sea tributaries. Intra- and Intergeneric Hybridization among Caucasian barbines was revealed for the first time. In the present study, we report the discovery of B. escherichii in the Kuban basin, where only B. kubanicus was known to inhabit. Hybrids of these two species were detected based on both mtDNA and nDNA markers. Remarkably, the Kuban population of B. escherichii is distant to closely located conspecific populations, and we consider it as a relic. We reveal the Intergeneric Hybridization between evolutionary tetraploid (2n=100) B. goktschaicus and evolutionary hexaploid (2n=150) Capoeta sevangi in Lake Sevan.
Gary W Saunders - One of the best experts on this subject based on the ideXlab platform.
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an evaluation of methods used to assess Intergeneric Hybridization in kelp using pacific laminariales phaeophyceae
Journal of Phycology, 2005Co-Authors: Louis D Druehl, Julie D Collins, Christopher E Lane, Gary W SaundersAbstract:Kelp Intergeneric laminarialean Hybridizations and Hybridization protocol were assessed using seven northeast Pacific kelp species: Alaria marginata Postels and Ruprecht, Costaria costata (C. A. Agardh) Saunders, Eisenia arborea Areschoug, Laminaria saccharina (L) Lamouroux, Lessoniopsis littoralis (Tilden) Reinke, Macrocystis integrifolia Bory, and Nereocystis leutkeana (Mertens) Postels and Ruprecht. Survival and development of sporophyte morphologies derived from selfings, separate males and females, and reciprocal crosses were evaluated over 30 weeks- of cultivation. All cultures were initiated from cloned gametophytes. Two closely related species, Laminaria angustata Kjellman and L. japonica Areschoug, demonstrated the efficacy of long-term (up to 30 years) cloned gametophytes in Hybridization studies. Sporophyte morphologies appeared in 34%-69% of control and Hybridization trials, and 6%-16% of all trials produced sporophytes in control and Hybridization conditions that persisted through 30 weeks of cultivation. Sporophytes in control and Hybridization conditions could appear normal or abnormal. Usually, the morphology of sporophytes in Hybridizations and female controls resembled the female parent, whereas the sporophytes in male controls often had an abbreviated morphology, lacking definitive generic features. Species-specific rDNA internal transcribed spacer molecular primers were used to determine the parentage of five putative hybrids. Only the L. japonica♀/L. angustata ♂ hybrid bore both parental genomes. That negative controls could produce persistent and normal-appearing sporophytes negates their value and emphasizes the importance of molecular confirmation in Hybridization studies. These findings were applied to critique the only known wild Intergeneric hybrid, Pelagophycus/Macrocystis.
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an evaluation of methods used to assess Intergeneric Hybridization in kelp using pacific laminariales phaeophyceae
Journal of Phycology, 2005Co-Authors: Louis D Druehl, Julie D Collins, Christopher E Lane, Gary W SaundersAbstract:Kelp Intergeneric laminarialean Hybridizations and Hybridization protocol were assessed using seven northeast Pacific kelp species: Alaria marginata Postels and Ruprecht, Costaria costata (C. A. Agardh) Saunders, Eisenia arborea Areschoug, Laminaria saccharina (L) Lamouroux, Lessoniopsis littoralis (Tilden) Reinke, Macrocystis integrifolia Bory, and Nereocystis leutkeana (Mertens) Postels and Ruprecht. Survival and development of sporophyte morphologies derived from selfings, separate males and females, and reciprocal crosses were evaluated over 30 weeks- of cultivation. All cultures were initiated from cloned gametophytes. Two closely related species, Laminaria angustata Kjellman and L. japonica Areschoug, demonstrated the efficacy of long-term (up to 30 years) cloned gametophytes in Hybridization studies. Sporophyte morphologies appeared in 34%-69% of control and Hybridization trials, and 6%-16% of all trials produced sporophytes in control and Hybridization conditions that persisted through 30 weeks of cultivation. Sporophytes in control and Hybridization conditions could appear normal or abnormal. Usually, the morphology of sporophytes in Hybridizations and female controls resembled the female parent, whereas the sporophytes in male controls often had an abbreviated morphology, lacking definitive generic features. Species-specific rDNA internal transcribed spacer molecular primers were used to determine the parentage of five putative hybrids. Only the L. japonica♀/L. angustata ♂ hybrid bore both parental genomes. That negative controls could produce persistent and normal-appearing sporophytes negates their value and emphasizes the importance of molecular confirmation in Hybridization studies. These findings were applied to critique the only known wild Intergeneric hybrid, Pelagophycus/Macrocystis.
