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1.
PLoS One ; 12(3): e0174902, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28358848

RESUMO

Extant Feliformia species are one of the most diverse radiations of Carnivora (~123 species). Despite substantial recent interest in their conservation, diversification, and systematic study, no previous phylogeny contains a comprehensive species set, and no biogeography of this group is available. Here, we present a phylogenetic estimate for Feliformia with a comprehensive species set and establish a historical biogeography based on mitochondrial DNA. Both the Bayesian and maximum likelihood phylogeny for Feliformia are elucidated in our analyses and are strongly consistent with many groups recognized in previous studies. The mitochondrial phylogenetic relationships of Felidae were for the first time successfully reconstructed in our analyses with strong supported. When divergence times and dispersal/vicariance histories were compared with historical sea level changes, four dispersal and six vicariance events were identified. These vicariance events were closely related with global sea level changes. The transgression of sea into the lowland plains between Eurasia and Africa may have caused the vicariance in these regions. A fall in the sea level during late Miocene to Pliocene produced the Bering strait land bridge, which assisted the migration of American Feliformia ancestors from Asia to North America. In contrast with the 'sweepstakes hypothesis', our results suggest that the climate cooling during 30-27 Ma assisted Feliformia migration from the African mainland to Madagascar by creating a short-lived ice bridge across the Mozambique Channel. Lineages-through-time plots revealed a large increase in lineages since the Mid-Miocene. During the Mid-Miocene Climatic Optimum, the ecosystems and population of Feliformia rapidly expanded. Subsequent climate cooling catalyzed immigration, speciation, and the extinction of Feliformia.


Assuntos
Carnívoros/genética , DNA Mitocondrial/genética , Animais , Teorema de Bayes , Carnívoros/classificação , Funções Verossimilhança , Filogenia
2.
Mitochondrial DNA B Resour ; 2(2): 486-488, 2017 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-33473872

RESUMO

The complete mitogenome sequence of the masked shrew (Sorex caecutiens) was determined using long PCR. The genome was 17,096 bp in length and contained 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes, one origin of L strand replication, and one control region. The overall base composition of the heavy strand is A (32.9%), C (24.5%), T (29.3%), and G (13.3%). The base compositions present clearly the A-T skew, which is most obviously in the control region and protein-coding genes. The extended termination-associated sequence domain, the central conserved domain and the conserved sequence block domain are defined in the mitochondrial genome control region of the masked shrew. Mitochondrial genome analyses based on MP, ML, NJ, and Bayesian analyses yielded identical phylogenetic trees. The five Sorex species formed a monophyletic group with the high bootstrap value (100%) in all examinations.

3.
Cell Biol Int ; 40(1): 7-15, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26109144

RESUMO

Many transgenes are silenced in mammalian cells (donor cells used for somatic cell nuclear transfer [SCNT]). Silencing correlated with a repressed chromatin structure or suppressed promoter, and it impeded the production of transgenic animals. Gene transcription studies in live cells are challenging because of the drawbacks of reverse-transcription polymerase chain reaction and fluorescence in situ hybridization. Nano-flare probes provide an effective approach to detect RNA in living cells. We used 18S RNA, a housekeeping gene, as a reference gene. This study aimed to establish a platform to detect RNA in single living donor cells using a Nano-flare probe prior to SCNT and to verify the safety and validity of the Nano-flare probe in order to provide a technical foundation for rescuing silenced transgenes in transgenic cloned embryos. We investigated cytotoxic effect of the 18S RNA-Nano-flare probe on porcine fetal fibroblasts, characterized the distribution of the 18S RNA-Nano-flare probe in living cells and investigated the effect of the 18S RNA-Nano-flare probe on the development of cloned embryos after SCNT. The cytotoxic effect of the 18S RNA-Nano-flare probe on porcine fetal fibroblasts was dose-dependent, and 18S RNA was detected using the 18S RNA-Nano-flare probe. In addition, treating donor cells with 500 pM 18S RNA-Nano-flare probe did not have adverse effects on the development of SCNT embryos at the pre-implantation stage. In conclusion, we established a preliminary platform to detect RNA in live donor cells using a Nano-flare probe prior to SCNT.


Assuntos
Corantes Fluorescentes/química , Hibridização in Situ Fluorescente/métodos , Técnicas de Transferência Nuclear , Hibridização de Ácido Nucleico/métodos , RNA Ribossômico 18S/análise , Doadores de Tecidos , Animais , Animais Geneticamente Modificados , Carbocianinas/química , Clonagem de Organismos , Feminino , Fibroblastos/citologia , Expressão Gênica , Inativação Gênica , Engenharia Genética , Nanopartículas Metálicas , Oócitos/citologia , Oócitos/metabolismo , RNA Ribossômico 18S/genética , Suínos , Transgenes
4.
Asian-Australas J Anim Sci ; 28(12): 1703-12, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26580437

RESUMO

The in vitro maturation (IVM) efficiency of porcine embryos is still low because of poor oocyte quality. Although brilliant cresyl blue positive (BCB+) oocytes with low glucose-6-phosphate dehydrogenase (G6PDH) activity have shown superior quality than BCB negative (-) oocytes with high G6PDH activity, the use of a BCB staining test before IVM is still controversial. This study aimed to shed more light on the subcellular characteristics of porcine oocytes after selection using BCB staining. We assessed germinal vesicle chromatin configuration, cortical granule (CG) migration, mitochondrial distribution, the levels of acetylated lysine 9 of histone H3 (AcH3K9) and nuclear apoptosis features to investigate the correlation between G6PDH activity and these developmentally related features. A pattern of chromatin surrounding the nucleoli was seen in 53.0% of BCB+ oocytes and 77.6% of BCB+ oocytes showed peripherally distributed CGs. After IVM, 48.7% of BCB+ oocytes had a diffused mitochondrial distribution pattern. However, there were no significant differences in the levels of AcH3K9 in the nuclei of blastocysts derived from BCB+ and BCB- oocytes; at the same time, we observed a similar incidence of apoptosis in the BCB+ and control groups. Although this study indicated that G6PDH activity in porcine oocytes was correlated with several subcellular characteristics such as germinal vesicle chromatin configuration, CG migration and mitochondrial distribution, other features such as AcH3K9 level and nuclear apoptotic features were not associated with G6PDH activity and did not validate the BCB staining test. In using this test for selecting porcine oocytes, subcellular characteristics such as the AcH3K9 level and apoptotic nuclear features should also be considered. Adding histone deacetylase inhibitors or apoptosis inhibitors into the culture medium used might improve the efficiency of IVM of BCB+ oocytes.

5.
Ying Yong Sheng Tai Xue Bao ; 25(2): 620-4, 2014 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-24830265

RESUMO

Genetic diversity is the base of the species diversity and ecosystem diversity, and also the foundation for biological evolution and species differentiation. Furthermore, genetic diversity is important evidence for evaluation of biological resources of nature. The genetic diversity data from a wide variety of rodents have many complex applications. We summarized the application of rodent prevention, the origin and differentiation including evolutionary history of rodents, the potential adaptation of rodents, the dynamics of population and regulatory mechanisms, and the conservation biology of rodents. Researches in the future should focus on the systematic study on the relationships between population dynamics and genetic diversity, and long-term monitoring of genetic diversity of rodents.


Assuntos
Variação Genética , Roedores/genética , Animais , Evolução Biológica , Dinâmica Populacional
6.
Dongwuxue Yanjiu ; 34(1): 8-13, 2013 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-23389972

RESUMO

Here, we present our findings of free-flying echolocation calls of Himalayan swiftlets (Aerodramus brevirostris), which were recorded in Shenjing Cave, Hupingshan National Reserve, Shimen County, Hunan Province in June 2012, using Avisoft-UltraSoundGate 116(e). We noted that after foraging at dusk, the Himalayan swiftlets flew fast into the cave without clicks, and then slowed down in dark area in the cave, but with sounds. The echolocation sounds of Himalayan swiftlets are broadband, double noise burst clicks, separated by a short pause. The inter-pulse intervals between double clicks (99.3±3.86 ms)were longer than those within double clicks (6.6±0.42 ms) (P<0.01). With the exception of peak frequency, between 6.2±0.08 kHz and 6.2±0.10 kHz, (P>0.05) and pulse duration 2.9±0.12 ms, 3.2±0.17 ms, (P>0.05) between the first and second, other factors-maximum frequency, minimum frequency, frequency bandwidth, and power-were significantly different between the clicks. The maximum frequency of the first pulse (20.1±1.10 kHz) was higher than that of second (15.4±0.98 kHz) (P<0.01), while the minimum frequency of the first pulse (3.7±0.12 kHz) was lower than that of second (4.0±0.09 kHz) (P<0.05); resulting in the frequency bandwidth of the first pulse (16.5±1.17 kHz) longer than that of second (11.4±1.01 kHz) (P<0.01). The power of the first pulse (-32.5±0.60 dB) was higher than that of second (-35.2±0.94 dB) (P<0.05). More importantly, we found that Himalayan swiftlets emitted echolocation pulses including ultrasonic sound, with a maximum frequency reaching 33.2 kHz.


Assuntos
Aves/fisiologia , Ecolocação/fisiologia , Voo Animal/fisiologia , Vocalização Animal/fisiologia , Animais , Som , Espectrografia do Som/métodos
7.
Zootaxa ; 3736: 397-400, 2013 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-25112639

RESUMO

Two new species Hemielimaea (Hemielimaea) paracari sp. nov. and H. (H.) parva sp. nov. from southwestern China are described. Characteristics of the stridulatory file on underside of male left tegmen, male stridulatory area on left and right tegmen, and abdominal apex of male are provided. Important and necessary illustrations of the new species are presented. Materials come from the following two depositories: Institute of Zoology, Chinese Academy of Sciences, Beijing, China (IZCAS), and China Agricultural University, Beijing, China (CAU).


Assuntos
Insetos/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Animais , China , Ecossistema , Insetos/anatomia & histologia , Masculino
8.
Dongwuxue Yanjiu ; 33(4): 355-61, 2012 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-22855441

RESUMO

Using simultaneous land surveys, we monitored the population size and spatial distribution of wintering Siberian cranes at 64 lakes around Poyang Lake between 1998 and 2010. The results showed that 46 lakes were inhabited by wintering cranes, and in 25 of those, the number of wintering cranes accounted for more than 1% of the Siberian cranes' global population. The lakes where over 40.0% of the global population, e.g. 1 280 individuals, included Dachahu Lake in Jiujiang region, and Banghu Lake and Candouhu Lake in the Poyang Lake Nature Reserve. The average yearly population of the wintering Siberian crane in the Poyang lakes was 3 108±849, with the maximum of 4 004 individuals in winter 2002. On the whole, there was no drastic fluctuation, but population numbers have shown considerable fluctuation since 2003. We also found the Poyang Lake Nature Reserve was the major wintering area of the Siberian crane, with over 60% of Siberian cranes wintering in the reserve since 2002 (except in 2006). Most of the inhabited lakes are covered in existing nature reserves, though some lakes outside the reserve were also considerably used by Siberian cranes.


Assuntos
Aves/crescimento & desenvolvimento , Animais , China , Ecossistema , Lagos , Densidade Demográfica , Estações do Ano
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