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1.
Genetika ; 39(4): 519-24, 2003 Apr.
Artigo em Russo | MEDLINE | ID: mdl-12760252

RESUMO

The cardiac portion of the stomach is lined with macrovilli in a few rodent genera. These are Mystromys (Cricetinae, Cricetidae), Myospalax (Myospalacinae, Cricetidae), Tachyoryctes (Tachyoryctinae, Cricetidae), and Cryptomys (Bathyergidae). The macrovilli favor the development of symbiotic flora and are called symbiovilli. Growth of the corneal epithelium of the cardiac portion of the stomach serves as a morphological basis of symbiovilli. Cases of a hereditary malignant neoplasm giving rise to the formation of multiple macrovilli in the cardiac portion of the stomach have been found in Microtus abbreviatus (Microtinae, Cricetidae), a vole endemic to St. Matthew Island in the Bering Sea. The macrovilli resulting from the papillomatosis mutation are morphologically and histologically identical to the macrovilli of the stomach of the four aforementioned genera. The voles affected with papillomatosis still survive long enough to reproduce. Therefore, the macromutation that leads to death in adult and old voles has been fixed as a species character in some rodent genera. At the early stages of papillomatosis, the pathogenic morphogenesis creates favorable conditions for the development of symbiotic microflora, which gives a selective advantage to the affected animals. It is assumed that mutations with pathogenic effects have been fixed as a species character as a result of heterochrony. The pathogenic neoplasm serves as a preadaptation for the growth of symbiotic flora in the stomach. The mechanisms of the fixation of Goldschmidt's "systemic mutations" during phylogeny are discussed.


Assuntos
Papiloma/patologia , Doenças dos Roedores/patologia , Roedores/genética , Estômago/patologia , Adaptação Fisiológica , Animais , Arvicolinae , Evolução Biológica , Microvilosidades/microbiologia , Microvilosidades/patologia , Mutação , Papiloma/etiologia , Doenças dos Roedores/genética , Roedores/classificação , Estômago/microbiologia , Simbiose/fisiologia
2.
Genetika ; 35(6): 756-64, 1999 Jun.
Artigo em Russo | MEDLINE | ID: mdl-10505265

RESUMO

Genetic distances between eight species of sousliks (Spermophilus) and five species of marmots (Marmota) were estimated on the basis of 39 biochemical loci. All taxa were shown to be genetically discrete. The genetic differentiation was minimal (Pfd = 11.3) between parapatric species of Palearctic sousliks of the suslicus pigmaeus group and Marmota species, intermediate (Pfd = 34.7) between allopatric sousliks species, and maximal (Pfd = 56.7) between representatives of different genera. The following trends were revealed in the geographic differentiation of the genus Spermophilus: (1) genetic similarity was associated with the geographic distance; (2) the eastern and western Palearctic phyla were markedly different genetically; (3) the eastern Palearctic forms exhibited higher differentiation than the western ones. The revealed speciation pattern is consistent with the general trend of temporal differentiation in Palearctic phyla and confirms the periodic speciation mode in the Palearctics.


Assuntos
Sciuridae/genética , Animais , Regiões Árticas , Proteínas Sanguíneas/genética , Eletroforese em Gel de Poliacrilamida , Esterases/genética , Variação Genética , Sciuridae/classificação , Especificidade da Espécie
3.
Genetika ; 35(2): 378-84, 1999 Mar.
Artigo em Russo | MEDLINE | ID: mdl-10368787

RESUMO

Eleven enzyme and four nonenzyme protein systems controlled by 25 loci were electrophoretically analyzed in the allopatric karyotypic forms (2n = 34 and 2n = 36) of the spotted souslik Spermophilus suslicus. Genetic variability and differentiation for the forms with different chromosome sets were estimated. Two discriminative loci (Alb and Tf) for the studied chromosome forms were found. The UPGMA dendrogram was constructed, which summarizes genetic (allozyme) relationships found for the forms of the spotted souslik with different chromosome sets. Subdividing the species into two karyotypic forms was shown to be followed by differentiating these forms at the allozyme level.


Assuntos
Cromossomos , Enzimas/genética , Genética Populacional , Sciuridae/genética , Animais , Cariotipagem
4.
Syst Biol ; 48(4): 715-34, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12066297

RESUMO

There are 14 species of marmots distributed across the Holarctic, and despite extensive systematic study, their phylogenetic relationships remain largely unresolved. In particular, comprehensive studies have been lacking. A well-supported phylogeny is needed to place the numerous ecological and behavioral studies on marmots in an evolutionary context. To address this situation, we obtained complete cytochrome (cyt) b sequences for 13 of the species and a partial sequence for the 14th. We applied a statistical approach to both phylogeny estimation and hypothesis testing, using parsimony and maximum likelihood-based methods. We conducted statistical tests on a suite of previously proposed hypotheses of phylogenetic relationships and biogeographic histories. The cyt b data strongly support the monophyly of Marmota and a western montane clade in the Nearctic. Although some other scenarios cannot be rejected, the results are consistent with an initial diversification in North America, followed by an invasion and subsequent rapid diversification in the Palearctic. These analyses reject the two major competing hypotheses of M. broweri's phylogenetic relationships--namely, that it is the sister species to M. camtschatica of eastern Siberia, and that it is related closely to M. caligata of the Nearctic. The Alaskan distribution of M. broweri is best explained as a reinvasion from the Palearctic, but a Nearctic origin can not be rejected. Several other conventionally recognized species groups can also be rejected. Social evolution has been homoplastic, with large colonial systems evolving in two groups convergently. The cyt b data do not provide unambiguous resolution of several basal nodes in the Palearctic radiation, leaving some aspects of pelage and karyotypic evolution equivocal.


Assuntos
Evolução Molecular , Geografia , Marmota/classificação , Filogenia , Animais , Sequência de Bases , Grupo dos Citocromos b/genética , Primers do DNA , Marmota/genética
5.
Genetika ; 35(12): 1687-98, 1999 Dec.
Artigo em Russo | MEDLINE | ID: mdl-10687096

RESUMO

The broad autosomal polymorphism in form obscurus of common voles Microtus arvalis from the Transcaucasian region that is associated with the variation of subtelocentric chromosome pair 5, as well as the mechanism and evolutionary significance of this polymorphism, are discussed. Based on the morphological analysis of heterozygotes for chromosome pair 5 after differential G-, C-, and Ag-NOR-banding and on the measurements of homologues, the following conclusion has been made. The occurrence of the acrocentric chromosome 5 is the result of a double chromosomal rearrangement: a pericentric inversion and a duplication of the chromosomal material. The mutation has been found throughout the entire territory of Armenia. In spite of such a wide distribution, the mutation frequency in populations is extremely low. Neither a definite pattern of geographic distribution nor a clinal variation was found for this mutation. This mutation is likely to occur independently in different M. arvalis populations and is apparently neutral. Homozygotes for chromosome pair 5 are described for the first time.


Assuntos
Arvicolinae/genética , Polimorfismo Genético , Animais , Feminino , Homozigoto , Cariotipagem , Mutação
6.
In. Craig Conklin, W; Blue,Charles; Nanko,Lisa; Carpentier, Marcia; Wyvill, Bonnie; Kahn, Miles; Nawar, Madeleine; Lyman,Rick. Proceedings of the 1998 international radiological post - emergency response issues conference. Washington, D.C, U.S. Environmental Protection Agency (EPA). Office of Radiation and Indoor Air, Sept. 1998. p.160-4.
Monografia em En | Desastres | ID: des-10896
7.
Genetika ; 34(5): 650-61, 1998 May.
Artigo em Russo | MEDLINE | ID: mdl-9719913

RESUMO

The primary sequence of a 402-bp part of the cytochrome b gene was determined in nine species of wood and field mice of the genus Apodemus. The majority of mutations were synonymous. The total number of transitions exceeded than of transversions. Among all substitutions, C-T transitions prevailed (51%); the most common substitution type in genus-specific sites was C-A transversions (42%). In interpopulation analysis, only transitions were recorded. A phylogenetic tree, constructed with the use of the neighbor-joining method, showed that the genus Apodemus is divided into three highly divergent groups: south Asian (Apodemus argenteus, A. semotus), east Asian (A. speciosus, A. agrarius), and Eurocaucasian (A. sylvaticus, A. flavicollis, A. uralensis, A. ponticus, A. flavipectis). The mean genetic distances within each group were 12.6, 11.2, and 8.8%, respectively. The species of the first group are more remote genetically and ancestrally with regard to the other groups. The interspecies divergence estimated for A. speciosus ranged from 0.25 to 3.75%. Thus, the evolutionary age of the genus Apodemus is about 6 Myr, and time of divergence of A. speciosus populations is 0.1-1.5 Myr. The phylogeny inferred from the data on the sequence of the cytochrome b gene in Apodemus mtDNA is somewhat different from similar phylogenies based on other genetic data and from the zoological taxonomy of wood and field mice. However, the above classification of species is confirmed by features of their karyotypes and segmentation of satDNA, and by the RFLP of total nDNA and isozyme polymorphism. Our results are in good agreement with the new classification of wood and field mice recently proposed by Russian zoologists.


Assuntos
Grupo dos Citocromos c/genética , DNA Mitocondrial/genética , Muridae/genética , Animais , Sequência de Bases , Primers do DNA , Evolução Molecular , Dados de Sequência Molecular , Muridae/classificação , Filogenia , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie
8.
J Hered ; 89(3): 266-9, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9656470

RESUMO

Severtzov's sheep (Ovis ammon severtzovi; Nasonov 1914) has a 2n = 56 diploid chromosome number and a karyotype consisting of two pairs of biarmed and 25 pairs of acrocentric autosomes, a large acrocentric X, and a minute biarmed Y. The G-banding patterns of the largest pair of biarmed chromosomes were identical to those of the largest biarmed chromosomes in all wild and domestic sheep of the genus Ovis. The banding patterns of the second pair of biarmed chromosomes were identical to the third pair of biarmed chromosomes in all sheep of the genus Ovis with 2n = 54 and to the third largest pair of chromosomes in the 2n = 52 karyotype of the Siberian snow sheep (O. nivicola). The G-banded karyotype of Severtzov's sheep is consistent with all subspecies of argali (O. ammon spp.) that have been karyotyped. Numerical ascription of acrocentric chromosome equivalents based upon the fundamental karyotype of Ovis that gave rise to the biarmed chromosomes of severtzovi are 1 and 3, and 5 and 11 for the largest and second largest biarmed chromosomes, respectively. Based upon diploid chromosome number and G bands, Severtzov's sheep should be considered a subspecies of argali and not a urial.


Assuntos
Cariotipagem/veterinária , Ovinos/genética , Animais , Animais Selvagens , Bandeamento Cromossômico/veterinária , Masculino , Especificidade da Espécie
9.
Genetika ; 34(2): 213-25, 1998 Feb.
Artigo em Russo | MEDLINE | ID: mdl-9589852

RESUMO

Data on the complex genetic analysis of three sympatric species of Caucasian wood mice, Apodemus ponticus, A. fulvipectus, and A. uralensis are presented. A high degree of genetic differentiation at the isozymic, karyological and molecular (nuclear DNA) levels was revealed. The genetic distances between each pair of species varied significantly within a wide range depending on the analyzed level of the organization of genetic material. Mean values of genetic divergence from one species to another were also variable. These findings indicated that evolution of chromosomes was slower than that of isozymes, and the degree of species divergence was similar on cytogenetic and molecular levels. They also suggested that the rates of species evolution could vary in different phyletic lineages and on different levels of organization. Some phyletic lineages of Apodemus could be distinguished by different directions of evolution.


Assuntos
DNA/genética , Evolução Molecular , Isoenzimas/genética , Muridae/genética , Animais , Cariotipagem , Mapeamento por Restrição , Especificidade da Espécie
10.
Genetika ; 33(6): 852-4, 1997 Jun.
Artigo em Russo | MEDLINE | ID: mdl-9289424

RESUMO

A rare case of chromosome variability is described for the ground vole, Terricola majori, from the Lagodekhi Nature Reserve (Georgia). This species is characterized by a stable karyotype (2n = 54, NF = 60), but we found an animal in which 2n = 53, NF = 60. The change in the diploid number resulted from a Robertsonian translocation accompanied by a local amplification of satellite sequences in centrometric heterochromatin. This structural rearrangement is probably a neutral mutation and is described for forest T. majori voles for the first time.


Assuntos
Arvicolinae/genética , Aberrações Cromossômicas , Mutação , Animais , Centrômero , DNA Satélite , Diploide , Feminino , República da Geórgia , Heterocromatina/genética , Cariotipagem , Translocação Genética
11.
C R Acad Sci III ; 319(5): 435-41, 1996 May.
Artigo em Francês | MEDLINE | ID: mdl-8763743

RESUMO

It has been suggested that the house mouse, Mus musculus, is a polytypic species that originated in the northern part of the Indian sub-continent. Its subspecies have established secondary contact zones in east-centre China and in western Europe. However, the exact colonization routes taken by these subtaxa and their regions of primary differentiation have not yet been identified. We analyzed 89 mice from Transcaucasia at 35 enzyme loci and for polymorphism of the mitochondrial control region and a deletion of the Y chromosome. The various samples analyzed are a mosaic of populations intermediates between M. m. domesticus and M. m. musculus. Trancaucasia appears thus as a broad secondary contact zone, a fact which reinforces the idea that the species has retained large possibilities of remixing.


Assuntos
Muridae/genética , Animais , DNA/genética , Genótipo , Isoenzimas/genética , Muridae/classificação , Transcaucásia , Cromossomo Y
12.
Genetika ; 31(6): 820-4, 1995 Jun.
Artigo em Russo | MEDLINE | ID: mdl-7635320

RESUMO

The genomes of three species of wood mouse (Apodemus falzfeini and A. ponticus from the Caucasus and A. argenteus from Japan) were compared by means of restriction analysis of nuclear DNA. The species are differentiated from each other and from previously studies species. Each species has its species-specific features. Within the genus Apodemus, A. ponticus is most closely related to the European species A. sylvaticus and A. flavicollis. A. falzfeini has a peculiar type of restriction with EcoR I (specific for dispersed repeats) and Hind III (specific for satDNA). The genome of this species contains three families of EcoR I repeats previously found in various species (European and Asian) of wood mouse and Hind III components characteristic of both wood and field mice. A. argenteus differs from all other forms of Apodemus, the genome of which contains the 375-bp Hind III satellite, by the presence of a EcoR I satDNA fraction consisting of 240-bp repeating units.


Assuntos
Muridae/genética , Animais , Regiões Árticas , DNA/genética , Muridae/classificação , Mapeamento por Restrição , Especificidade da Espécie
13.
Genetika ; 28(11): 111-21, 1992 Nov.
Artigo em Russo | MEDLINE | ID: mdl-1286795

RESUMO

Genetic relations between four European mice species of the genus Apodemus (Apodemus sylvaticus, A. flavicollis, A. microps and A. falzfeini) and five Transcaucasian ones (A. mystacinus, A. microps, and the forms No 2, 3p, 3f) were studied for 37 biochemical loci. Close genetic relations were demonstrated between the mice of subgenus Sylvaemus and A. mystacinus. A. microps and A. falzfeini from the Caucasus were shown conspecific to these species from the Ukraine and the presence of the two new different species--the form No 2 and 3p in the Caucasus was established.


Assuntos
Mapeamento Cromossômico/métodos , Muridae/genética , Animais
14.
Zh Obshch Biol ; 50(6): 737-45, 1989.
Artigo em Russo | MEDLINE | ID: mdl-2694675

RESUMO

Unjustified narrowing of the problems of morphology by merging the terms "morphology" and "anatomy" leads to stagnation in morphology. The merging of "classic" and "modern" biology will enrich both morphology and molecular biology and genetics. The latter will be able apply conceptual models of morphology to more primitive structural level of life. The possibility to apply V. A. Dogel' 's ideas on the role of oligomerization and polymerization in science to the analysis of molecular evolution has been demonstrated with the analysis of DNA content in the genomes of Chordata taken as an example. The data on DNA content do not allow both to consider lungfishes as ancestors of all Tetrapoda and develop monophyletic concept of Tetrapoda origin at the same time. The possibility of application of concepts of comparative morphology to analysis of molecular evolution has been considered.


Assuntos
Anatomia/métodos , Animais , Evolução Biológica , DNA/genética , Técnicas Genéticas , Técnicas Histológicas , Biologia Molecular/métodos , Filogenia , Terminologia como Assunto
15.
Artigo em Russo | MEDLINE | ID: mdl-2658436

RESUMO

The dynamic determination of the presence of the specific antigen and its activity in the excreta of humans subjected to enteral immunization with vaccine prepared from S. flexneri antigen was made in the agglutination test and neutralization test with the use of, respectively, antibody and antigenic erythrocyte diagnosticums. In the feces and urine of the vaccinees antibodies occurred less commonly and, as a rule, they were less active than those detected in dysentery patients at the corresponding time from the beginning of the disease. The occurrence of Shigella antigens in the feces of the vaccinees was greater than in their urine at the corresponding time. Similarities and differences in the dynamics of the isolation of Shigella antigen from dysentery patients and from the vaccinees receiving enteral vaccine prepared from S. flexneri antigens were established.


Assuntos
Antígenos de Bactérias/análise , Disenteria Bacilar/diagnóstico , Shigella flexneri/imunologia , Vacinação , Adolescente , Antígenos de Bactérias/urina , Disenteria Bacilar/prevenção & controle , Fezes/análise , Humanos , Masculino
16.
Zh Mikrobiol Epidemiol Immunobiol ; (12): 72-6, 1988 Dec.
Artigo em Russo | MEDLINE | ID: mdl-2977464

RESUMO

The detection of Shigella antigens in feces in accordance with the results of the passive hemagglutination test is more effective than the bacteriological method for finding out persons infected with Shigella, especially in the absence of pronounced clinical manifestations of dysentery, and can be used in the study of the mechanism of the epidemic process. The examination of two groups, each consisting of permanent and temporary members, has revealed that the use of this method for detection of the antigen makes it possible to perform the epidemiological analysis of morbidity and, in particular, to determine the source(s) of infection.


Assuntos
Antígenos de Bactérias/análise , Surtos de Doenças , Disenteria Bacilar/epidemiologia , Shigella flexneri/imunologia , Convalescença , Disenteria Bacilar/imunologia , Disenteria Bacilar/microbiologia , Fezes/microbiologia , Testes de Hemaglutinação , Humanos , Cazaquistão , Shigella flexneri/isolamento & purificação , Fatores de Tempo
17.
Genetika ; 24(6): 1081-8, 1988 Jun.
Artigo em Russo | MEDLINE | ID: mdl-3049233

RESUMO

A brief survey of the development of concepts on the role of macromutations in evolution is given. Contrary to Iu. A. Filipchenko (1926, 1927), who introduced the "micro- and macromutation" terms and believed that regularities of macroevolution could not be reduced to microevolutionary processes, the majority of "synthetists" explained any form of evolution by changes in allele frequencies. From the studies of Drosophila homoeotic mutants R. Goldschmidt (1940) developed the concept of "hopeful monsters" and their role in macroevolution. However, the homoeotic mutants are of drastically reduced viability, which allows the gradualists to reject Goldschmidt's ideas. The distribution of hairlessness mutations (hairless, nude etc.) with the monogenic pattern of inheritance in mammals was studied. Hairless mutants are known in Peromyscus, Mus musculus, Rattus rattus, R. norvegicus, Canis familiaris, Ovis aries. Hairlessness as norm is found in 53 among contemporaneous 1037 mammalian genera. Part of these cases (hairlessness in all Cetacea and Sirenia) may be explained in terms of both macromutations and obligatory gradualism. There is no doubt as to the macromutational origin of hairlessness in the bat Cheiromeles and the rodent Heterocephalus (Bathyergidae); the genera systematically and ecologically close to these have normal pelage. It is quite possible that hairlessness of walrus (Odobenus) has the same origin. The appearance and fixation of single Goldschmidt's macromutation cannot yet be considered as a macroevolutionary process, though the possibility of fixation of a macromutation in nature as a species and genus character contradicts strongly the concept of obligatory gradualism of evolution.


Assuntos
Evolução Biológica , Cabelo , Mamíferos/genética , Mutação , Animais , Animais Domésticos , Animais de Laboratório , Animais Selvagens , Ratos , Especificidade da Espécie
19.
Mol Biol (Mosk) ; 11(4): 883-90, 1977.
Artigo em Russo | MEDLINE | ID: mdl-618331

RESUMO

Fifteen chromosome forms of Ellobius talpinus (from 2n = 31 to 2n = 54) were found in the small area in the Pamirs. Low-chromosome karyotypes evolved from 54-chromosomal ancestral form by Robertsonia centric fusions. The DNA reassociation kinetics of 34- and 54-chromosome forms of E. talpinus have been studied. For comparison DNA of E. lutescens (2n = 17) the karyotype of which seems to have arisen from 54-chromosome ancestor by Robertsonian and other types rearrangements was examined. Reassociation profiles of Ellobius DNA suggest the existence of several repeated sequences families with different frequences of repetitions. The reassociation curves of DNA from 34- and 54-chromosome forms were identical. These data indicate absence of changes in DNA molecular organization during the evolution of E. talpinus karyotypes by Robertsonian fusions. Comparative analysis of DNA reassociation kinetics of E. talpinus and E. lutescens showed identical characteristics of highly repeated sequences and of one from the three intermediate fractions, however Cot 1/2, complexity and repetitive frequencies of two intermediate fractions of E. talpinus and E. lutescens were different. It is possible that non-robertsonian rearrangements of E. lutescens karyotype affected only intermediate repetitions. The alternative explanation of these data is a simple divergence of repeated sequences during the evolution of E. lutescens DNA.


Assuntos
Cromossomos , DNA , Eulipotyphla/genética , Toupeiras/genética , Renaturação de Ácido Nucleico , Animais , Evolução Biológica , Feminino , Cinética , Masculino , Ratos , Especificidade da Espécie , U.R.S.S.
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