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1.
Virulence ; 12(1): 2430-2442, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34517779

RESUMO

Severe acute respiratory syndrome CoV-2 (SARS-CoV-2) is currently causing a worldwide threat with its unusually high transmission rates and rapid evolution into diverse strains. Unlike typical respiratory viruses, SARS-CoV-2 frequently causes systemic infection by breaking the boundaries of the respiratory systems. The development of animal models recapitulating the clinical manifestations of COVID-19 is of utmost importance not only for the development of vaccines and antivirals but also for understanding the pathogenesis. However, there has not been developed an animal model for systemic infection of SARS-CoV-2 representing most aspects of the clinical manifestations of COVID-19 with systemic symptoms. Here we report that a Roborovski hamster strain SH101, a laboratory inbred hamster strain of P. roborovskii, displayed most symptoms of systemic infection upon SARS-CoV-2 infection as in the case of the human counterpart, unlike current COVID-19 animal models. Roborovski hamster strain SH101 post-infection of SARS-CoV-2 represented most clinical symptoms of COVID-19 such as snuffling, labored breathing, dyspnea, cough, hunched posture, progressive weight loss, ruffled fur, and high fever following shaking chills. Histological examinations also revealed initial right-predominated pneumonia as well as slight organ damages in the brain and liver, manifesting systemic COVID-19 cases. Considering the merit of a small animal as well as its clinical manifestations of SARS-CoV-2 infection in human, this hamster model seems to provide an ideal tool to investigate COVID-19.


Assuntos
COVID-19 , Cricetinae/classificação , Modelos Animais de Doenças , SARS-CoV-2 , Animais , Temperatura Corporal , Encéfalo/patologia , COVID-19/patologia , COVID-19/fisiopatologia , Feminino , Fígado/patologia , Pulmão/patologia , Masculino , Mesocricetus , Camundongos , Camundongos Transgênicos
2.
Genes (Basel) ; 12(7)2021 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202749

RESUMO

The taxonomy of the genus Calomyscus remains controversial. According to the latest systematics the genus includes eight species with great karyotypic variation. Here, we studied karyotypes of 14 Calomyscus individuals from different regions of Iran and Turkmenistan using a new set of chromosome painting probes from a Calomyscus sp. male (2n = 46, XY; Shahr-e-Kord-Soreshjan-Cheshme Maiak Province). We showed the retention of large syntenic blocks in karyotypes of individuals with identical chromosome numbers. The only rearrangement (fusion 2/21) differentiated Calomyscus elburzensis, Calomyscus mystax mystax, and Calomyscus sp. from Isfahan Province with 2n = 44 from karyotypes of C. bailwardi, Calomyscus sp. from Shahr-e-Kord, Chahar Mahal and Bakhtiari-Aloni, and Khuzestan-Izeh Provinces with 2n = 46. The individuals from Shahdad tunnel, Kerman Province with 2n = 51-52 demonstrated non-centric fissions of chromosomes 4, 5, and 6 of the 46-chromosomal form with the formation of separate small acrocentrics. A heteromorphic pair of chromosomes in a specimen with 2n = 51 resulted from a fusion of two autosomes. C-banding and chromomycin A3-DAPI staining after G-banding showed extensive heterochromatin variation between individuals.


Assuntos
Cromossomos de Mamíferos/genética , Cricetinae/genética , Análise Citogenética , Evolução Molecular , Animais , Bandeamento Cromossômico , Cricetinae/classificação , Heterocromatina/genética , Hibridização in Situ Fluorescente , Irã (Geográfico) , Cariótipo , Camundongos/classificação , Camundongos/genética , Filogeografia , Especificidade da Espécie , Sintenia/genética , Turcomenistão
3.
Sci Rep ; 11(1): 10557, 2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-34006914

RESUMO

The genus status of Urocricetus was defined recently based on morphological and molecular data. Even though the amount of evidence for a separate phylogenetic position of this genus among Cricetinae continues to increase, there is still no consensus on its relationship to other groups. Here we give the first comprehensive description of the U. kamensis karyotype (2n = 30, NFa = 50) including results of comparative cytogenetic analysis and detailed examination of its phylogenetic position by means of numerous molecular markers. The molecular data strongly indicated that Urocricetus is a distant sister group to Phodopus. Comparative cytogenetic data showed significant reorganization of the U. kamensis karyotype compared to karyotypes of all other hamsters investigated earlier. The totality of findings undoubtedly means that Urocricetus belongs to a separate divergent lineage of Cricetinae.


Assuntos
Cricetinae/genética , Cariotipagem , Animais , Bandeamento Cromossômico , Cricetinae/classificação , Feminino , Masculino , Filogenia , Especificidade da Espécie
4.
Genomics ; 112(2): 1716-1725, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31669701

RESUMO

Both Cricetus cricetus and Phodopus sungorus mitochondrial genomes (mitogenomes) were sequenced and elaborated for the first time in the present study. Their mitogenomes contained 37 genes and showed typical characteristics of the vertebrate mitogenome. Comparative analysis of 10 cricetine mitogenomes indicated that they shared similar characteristics with those of other cricetines in terms of genes arrangement, nucleotide composition, codon usage, tRNA structure, nucleotide skew and the origin of replication of light strand. Phylogenetic relationship of the subfamily Cricetinae was reconstructed using mitogenomes data with the methods of Bayesian Inference and Maximum Likelihood. Phylogenetic analysis indicated that Cricetulus kamensis was at basal position and phylogenetically distant from all other Cricetulus species but had a close relationship with the group of Phodopus, and supported that the genus Urocricetus deserved as a separate genus rank. The phylogenetic status of Tscherskia triton represented a separate clade corresponding to a diversified cricetine lineage (Cricetulus, Allocricetulus, and Cricetus).


Assuntos
Cricetinae/genética , Genoma Mitocondrial , Filogenia , Animais , Cricetinae/classificação
5.
Evolution ; 68(11): 3134-48, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25130206

RESUMO

Mammalian hybrids often show abnormal growth, indicating that developmental inviability may play an important role in mammalian speciation. Yet, it is unclear if this recurrent phenotype reflects a common genetic basis. Here, we describe extreme parent-of-origin-dependent growth in hybrids from crosses between two species of dwarf hamsters, Phodopus campbelli and Phodopus sungorus. One cross type resulted in massive placental and embryonic overgrowth, severe developmental defects, and maternal death. Embryos from the reciprocal cross were viable and normal sized, but adult hybrid males were relatively small. These effects are strikingly similar to patterns from several other mammalian hybrids. Using comparative sequence data from dwarf hamsters and several other hybridizing mammals, we argue that extreme hybrid growth can contribute to reproductive isolation during the early stages of species divergence. Next, we tested if abnormal growth in hybrid hamsters was associated with disrupted genomic imprinting. We found no association between imprinting status at several candidate genes and hybrid growth, though two interacting genes involved in embryonic growth did show reduced expression in overgrown hybrids. Collectively, our study indicates that growth-related hybrid inviability may play an important role in mammalian speciation but that the genetic underpinnings of these phenotypes remain unresolved.


Assuntos
Cricetinae/genética , Hibridização Genética , Animais , Cricetinae/classificação , Cruzamentos Genéticos , Epigênese Genética , Impressão Genômica
6.
PLoS One ; 9(6): e99540, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24911266

RESUMO

Dispersal is a fundamental process in ecology influencing the genetic structure and the viability of populations. Understanding how variable factors influence the dispersal of the population is becoming an important question in animal ecology. To date, geographic distance and geographic barriers are often considered as main factors impacting dispersal, but their effects are variable depending on different conditions. In general, geographic barriers affect more significantly than geographic distance on dispersal. In rapidly expanding populations, however, geographic barriers have less effect on dispersal than geographic distance. The effects of both geographic distance and geographic barriers in low-density populations with patchy distributions are poorly understood. By using a panel of 10 microsatellite loci we investigated the genetic structure of three patchy-distributed populations of the Greater long-tailed hamster (Tscherskia triton) from Raoyang, Guan and Shunyi counties of the North China Plain. The results showed that (i) high genetic diversity and differentiation exist in three geographic populations with patchy distributions; (ii) gene flow occurs among these three populations with physical barriers of Beijing city and Hutuo River, which potentially restricted the dispersal of the animal; (iii) the gene flow is negatively correlated with the geographic distance, while the genetic distance shows the positive correlation. Our results suggest that the effect of the physical barriers is conditional-dependent, including barrier capacity or individual potentially dispersal ability. Geographic distance also acts as an important factor affecting dispersal for the patchy distributed geographic populations. So, gene flow is effective, even at relatively long distances, in balancing the effect of geographic barrier in this study.


Assuntos
Cricetinae , Animais , China , Cricetinae/classificação , Cricetinae/genética , Ecossistema , Evolução Molecular , Variação Genética , Genética Populacional , Geografia , Densidade Demográfica , Dinâmica Populacional
7.
Arch Oral Biol ; 56(2): 194-204, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20940068

RESUMO

OBJECTIVE: This study was designed to interpret the differences between the occlusal relationships in the murine rodents and those in their Miocene "cricetodont" ancestors. It aimed at understanding the functional transformations that led to the emergence of the peculiar chewing motion of the Murinae, associating forwardly directed masticatory movements to cusp interlocking, a trait unique amongst mammals. METHODS: Microwear analyses and simulations of occlusion achieved with size-increased 3D printings of teeth crafted from 3D data obtained by X-ray synchrotron microtomography at the European synchrotron radiation facility allow us to carefully interpret the occlusal relationships in Muroidea. RESULTS: A rotation of the direction of the chewing movements occurred from "Cricetodontinae" to Murinae. This rotation emerged without any cusp removal contrary to previous interpretations, by the way of an occlusal reorganization involving a loss of contacts between some cusps, offset by a contact with other cusps. This new organization was already present in the early and middle Miocene genus Potwarmus. CONCLUSION: Molar tooth evolution in Murinae was characterized by the preservation and the reshaping of the primitive muroid cusps, the acquisition of supplementary cusps, and changes in the contacts between the opposite cusps. During evolution, changes of cusp patterns in upper and lower molar teeth are coordinated in order to retain a functional occlusion. Because of this functional constraint, one cusp was supposed to more likely occlude with the same opposite cusps during evolution, and therefore homologous cusps would always carry homologous attrition facets. Evolution of Murinae proves that functional continuity can also be preserved through changes in occlusal relationships independently from cusp removal.


Assuntos
Evolução Biológica , Cricetinae/anatomia & histologia , Oclusão Dentária , Mastigação/fisiologia , Murinae/anatomia & histologia , Desgaste dos Dentes , Animais , Cricetinae/classificação , Dentição , Murinae/classificação , Filogenia
8.
Dongwuxue Yanjiu ; 31(3): 239-49, 2010 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-20672411

RESUMO

In order to study the structural, functional and molecular evolutional relationship of fish liportein lipase (LPL) and hepatic lipase (HL) genes, seven liver LPL and HL cDNA partial sequences were isolated from Acipenser sinensis, Hypophthalmichthys molitrix, Aristichthys nobilis, Ctenopharyngodon idellus, Cirrhinus molitorella, Oreochromis niloticus, Channa maculate by RT-PCR. Three full-length cDNA sequences of LPL, HL of Acipenser sinensis and LPL of Hypophthalmichthys molitrix were obtained by RACEs. From the sequence analysis and homologous results, the amino acid sequences of LPL and HL are relatively conserved in mammals, birds and fishes. Taken together with these obtained amino acid sequences and sequences of all known LPL, HL, EL and PL from other vertebrates, a phylogenetic tree was constructed by neighbor-joining method. The result supports that all of them belong to lipase family.


Assuntos
Cricetinae/genética , Cricetulus/genética , DNA Complementar/análise , Evolução Molecular , Peixes/genética , Lipase/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Carpas , Cricetinae/classificação , DNA Complementar/genética , Peixes/classificação , Água Doce , Lipase Lipoproteica/análise , Lipase Lipoproteica/genética , Dados de Sequência Molecular , Reação em Cadeia da Polimerase Via Transcriptase Reversa
9.
Emerg Infect Dis ; 15(2): 207-15, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19193264

RESUMO

Transmissible spongiform encephalopathy (TSE) diseases are known to cross species barriers, but the pathologic and biochemical changes that occur during transmission are not well understood. To better understand these changes, we infected 6 hamster species with 263K hamster scrapie strain and, after each of 3 successive passages in the new species, analyzed abnormal proteinase K (PK)-resistant prion protein (PrPres) glycoform ratios, PrPres PK sensitivity, incubation periods, and lesion profiles. Unique 263K molecular and biochemical profiles evolved in each of the infected hamster species. Characteristics of 263K in the new hamster species seemed to correlate best with host factors rather than agent strain. Furthermore, 2 polymorphic regions of the prion protein amino acid sequence correlated with profile differences in these TSE-infected hamster species.


Assuntos
Cricetinae/classificação , Cricetinae/metabolismo , Proteínas PrPSc/patogenicidade , Doenças Priônicas/transmissão , Sequência de Aminoácidos , Animais , Endopeptidase K/metabolismo , Imuno-Histoquímica , Dados de Sequência Molecular , Proteínas PrPSc/química , Proteínas PrPSc/genética , Doenças Priônicas/metabolismo , Doenças Priônicas/patologia , Príons/química , Príons/genética , Análise de Sequência de DNA , Inoculações Seriadas , Especificidade da Espécie
10.
Mol Phylogenet Evol ; 39(1): 135-48, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16483801

RESUMO

Despite some popularity of hamsters as pets and laboratory animals there is no reliable phylogeny of the subfamily Cricetinae available so far. Contradicting views exist not only about the actual number of species but also concerning the validity of several genera. We used partial DNA sequences of two mitochondrial (cytochrome b, 12S rRNA) and one partial nuclear gene (von Willebrand Factor exon 28) to provide a first gene tree of the Cricetinae based on 15 taxa comprising six genera. According to our data, Palaearctic hamsters fall into three distinct phylogenetic groups: Phodopus, Mesocricetus, and Cricetus-related species which evolved during the late Miocene about 7-12MY ago. Surprisingly, the genus Phodopus, which was previously thought to have appeared during the Pleistocene, forms the oldest clade. The largest number of extant hamster genera is found in a group of Cricetus-related hamsters. The genus Cricetulus itself proved to be not truly monophyletic with Cricetulus migratorius appearing more closely related to Tscherskia, Cricetus, and Allocricetulus. We propose to place the species within a new monotypic genus. Molecular clock calculations are not always in line with the dating of fossil records. DNA based divergence time estimates as well as taxonomic relationships demand a reevaluation of morphological characters previously used to identify fossils and extant hamsters.


Assuntos
Cricetinae/classificação , Cricetinae/genética , Evolução Molecular , Animais , Sequência de Bases , Citocromos b/genética , DNA Mitocondrial/genética , Genes de RNAr/genética , Dados de Sequência Molecular , Filogenia , RNA Ribossômico/genética , Fator de von Willebrand/genética
11.
Cytogenet Cell Genet ; 88(3-4): 296-304, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10828614

RESUMO

Karyotypes of Calomyscus from different regions of Turkmenistan, Iran, and Azerbaijan were studied using chromosome banding (G- and C-banding) and analyses of meiosis in laboratory hybrids. Extensive variation in the diploid number and the number of autosomal arms (FNa) was revealed (2n = 30, FNa = 44; 2n = 32, FNa = 42; 2n = 44, FNa = 46; 2n = 44, FNa = 58; 2n = 37, FNa = 44; 2n = 50, FNa = 50; 2n = 52, FNa = 56). Centric and tandem fusions and heterochromatin changes were identified as the major modes of karyotype evolution in this group. Natural hybrids between individuals with different karyotypes were recorded, and regular chromosome pairing in meiosis was observed in laboratory hybrids. Fluorescence in situ hybridization with a 353-bp BspRI complex tandem repeat indicated that chromosomal repatterning occurred recently within the genus. There is no unequivocal evidence suggesting the role of chromosomal change in the speciation of the populations of Calomyscus examined.


Assuntos
Bandeamento Cromossômico , Cricetinae/classificação , Cricetinae/genética , Hibridização in Situ Fluorescente , Animais , Azerbaijão , Sequência de Bases , Desoxirribonucleases de Sítio Específico do Tipo II/metabolismo , Diploide , Feminino , Geografia , Heterocromatina/genética , Hibridização Genética/genética , Irã (Geográfico) , Cariotipagem , Masculino , Microscopia Eletrônica , Dados de Sequência Molecular , Filogenia , Complexo Sinaptonêmico/genética , Sequências de Repetição em Tandem/genética , Turcomenistão
13.
Artigo em Inglês | MEDLINE | ID: mdl-2895541

RESUMO

We have carried out an electron microscopic and immunocytochemical study of thyroid medullary carcinoma arising spontaneously in the Djungarian hamster, Phodopus sungorus. At the ultrastructural level the cytoplasm of tumor cells contained numerous round to slightly elongated, dense-cored secretory granules. The number of secretory granules differed from cell to cell in the tumor, being scanty in some cells but more or less abundant in most. Electron microscopic-immunocytochemistry demonstrated that all dense-cored secretory granules in all tumor cells exhibited calcitonin immunoreactivity. In approximately 10% of the tumor cells, unusual star-shaped secretory vesicles were also found in the cytoplasm. These vesicles contained a small, but well-defined, lucent core surrounded by a region of finely granular material of greater electron density. The outer contour of these unusual vesicles was stellate rather than smooth. They appeared to originate not from the Golgi complex, but from the rough endoplasmic reticulum. These atypical stellate vesicles did not show any calcitonin immunoreactivity. Furthermore, in a small number of tumor cells (approximately 1%) a third type of membrane enclosed structure was found. These were conspicuous rods 1-5 micron in length with tapering ends and a crystalline substructure. The presence of both normal and atypical secretory granules in some tumor cells suggests that carcinogenic transformation may interfere with the normal synthesis and assembly of secretory products by the cell.


Assuntos
Carcinoma/ultraestrutura , Cricetinae/classificação , Grânulos Citoplasmáticos/metabolismo , Neoplasias da Glândula Tireoide/ultraestrutura , Animais , Grânulos Citoplasmáticos/ultraestrutura , Masculino , Microscopia Eletrônica
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