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1.
Mol Ecol ; 32(16): 4497-4514, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37332105

RESUMO

Continental East Asia has a mild Pleistocene climate and a complex recent geological history. Phylogeographic studies of animals over the last 30 years have produced several distinctive patterns. Glaciation refugia are numerous and are not restricted to any particular regions. Most of them are localized and species-specific, although several large refugia, for example the mountains of SW China, are shared by multiple species and have refugia-within-refugia. Furthermore, postglaciation range expansion events vary greatly in time, scale and direction. Large-scale south-to-north post-LGM expansions are few and mostly occurred in the northern regions. Additionally, several unique geographic features, including the three-step terrain of China and the northern arid belt, have significant impacts on many species histories. Overall, the impacts of Pleistocene glaciations, particularly the LGM, on species history vary drastically from nondetectable to significant. The impacts are the least for species from the southwestern region and are most dominant for species from the north. Geological events play a more significant role in shaping species history than Pleistocene climatic changes. Phylogeographic patterns among animals species are highly consistent with those of plants. Future phylogeographic endeavour in East Asia should be hypothesis-driven and seek processes that underlie common patterns. The wide use of genomic data allow accurate estimates of historical population processes and exploration of older history beyond the Pleistocene.


Assuntos
DNA Mitocondrial , Variação Genética , Animais , Filogenia , DNA Mitocondrial/genética , Filogeografia , Ásia Oriental
2.
Cogn Neurodyn ; 16(3): 719-731, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35603052

RESUMO

Bursting of midbrain dopamine (DA) neurons is believed to represent an important reward signal that instructs and reinforces goal-directed behaviors. In DA neurons, many afferents, including cholinergic and glutamatergic inputs, induce bursting, and it is suggested that a synergy exists between these afferents in bursting induction. However, the underlying mechanisms of the role and the synergy of muscarinic receptors (mAChRs) and NMDA receptors (NMDARs) in bursting induction remain unclear. Present work bestowed analysis using a mathematical model of DA neurons to demonstrate the underlying mechanisms. Activation of mAChRs, leading to rapid translocation of TRPC channels to cell surface, recruited C a 2 + -activated nonspecific (CAN) current ( I CAN ), meanwhile NMDARs excitation triggered C a 2 + influx, which induced the positive feedback loop of C a 2 + and I CAN , respectively, yielded a robust ramping depolarization with a superimposed high-frequency spiking. In some DA cells, neither NMDARs nor mAChRs induced positive feedback loop unless they were activated simultaneously to induce bursting. Our experimental results verified those theoretical findings. These together unveil the underlying mechanisms of the role and synergy of mAChRs and NMDARs in bursting induction emerge from the nonlinear relationship between C a 2 + influx and I CAN . Given the diverse and complex nature of neural circuitry and the DA neuron heterogeneity, our work provides new insights to understand specific afferents, the synergy between those afferents, and the differences in intrinsic excitability to be integrated by the bursting to accurately characterize the dopamine signals in the valances of reward and reinforcement, and a broad spectrum of neuropsychiatric disorders.

3.
Artigo em Inglês | MEDLINE | ID: mdl-26679731

RESUMO

The complete mitochondrial genome of the white-browed laughingthrush Garrulax sannio was assembled using next-generation sequencing (NGS) technology. The double-stranded circular genome is 17 848 bp in length, including 22 transfer RNAs (tRNAs), 13 protein-coding genes (PCGs), two ribosomal RNAs (rRNAs), and 2 putative control region. All PCGs are initiated with the ATG codon except for COX1 with GTG as its start codon. Five distinct types of stop codons are present, i.e., AGA (ND5), AGG (COX1 and ND1), TAA (ATP6, ATP8, COX2, CYTB, and ND4L), TAG (ND6), and the incomplete codon T/TA (COX3, ND2, ND3, and ND4). The nucleotide composition is moderately asymmetric (28.94% A, 32.82% C, 15.00% G, and 23.24% T) with an overall GC content of 47.82% ("light strand"). Phylogenetic analysis indicated a close genetic relationship between this species and its congeners G. perspicillatus, G. cineraceus, and G. canorus.


Assuntos
Genoma Mitocondrial , Passeriformes/genética , Animais , Proteínas Aviárias/química , Proteínas Aviárias/genética , Proteínas Aviárias/metabolismo , Composição de Bases , Códon de Iniciação , Códon de Terminação , DNA Mitocondrial/química , DNA Mitocondrial/isolamento & purificação , DNA Mitocondrial/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Fases de Leitura Aberta/genética , Passeriformes/classificação , Filogenia , RNA Ribossômico/química , RNA Ribossômico/genética , RNA de Transferência/química , RNA de Transferência/genética , Análise de Sequência de DNA
4.
Artigo em Inglês | MEDLINE | ID: mdl-26681602

RESUMO

The complete mitochondrial genome of the green-backed tit Parus monticolus was assembled from Illumina sequencing reads. The genome is 16 771 bp long, and harbors 22 transfer RNAs (tRNAs), 13 protein-coding genes (PCGs), two ribosomal RNAs (rRNAs), and one control region. All PCGs are initiated with the ATG codon except for COX1 with GTG as its start codon. Five distinct types of stop codons are inferred, i.e. AGA (ND1 and ND5), AGG (COX1), TAA (ATP6, ATP8, COX2, ND3 and ND4L), TAG (ND6), and the incomplete codon T/TA (COX3, CYTB, ND2 and ND4). The 22 tRNAs range in size from 66 to 75 bp. The 12S and 16S rRNAs are 982 and 1601 bp long, respectively, and are separated by tRNA-Val gene. The putative control region is located between tRNA-Glu and tRNA-Phe with a length of 1187 bp. Phylogenetic analysis indicated that this species is closely related to its congener P. major.


Assuntos
Genes Mitocondriais , Genoma Mitocondrial , Passeriformes/genética , Filogenia , Animais , Sequência de Bases , Códon , DNA Mitocondrial , Tamanho do Genoma , Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Análise de Sequência de DNA
5.
Mitochondrial DNA A DNA Mapp Seq Anal ; 28(1): 143-144, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-26710310

RESUMO

The complete mitochondrial genome of the fulvous parrotbill (Paradoxornis fulvifrons) has been determined from Illumina sequencing data. The circular genome is 17 059 bp long, comprising 37 genes (13 protein-coding genes/PCGs, 22 tRNA genes and two rRNA genes) and a putative control region. Except for COX1 with GTG as its start codon, all PCGs are initiated with the ATR (ATA/ATG) codons. One PCG (COX1) is terminated with AGG, three PCGs (COX3, ND2 and ND4) with the incomplete stop codon T--/TA-, while all the others with TAA. The 22 tRNAs range in size from 64 bp (tRNA-Ser) to 75 bp (tRNA-Leu). The two rRNAs are 982 bp (12S rRNA) and 1600 bp (16S rRNA) long, respectively. The putative control region is located between tRNA-Thr and tRNA-Pro genes with a length of 1235 bp. The base composition is biased (29.06% A, 31.10% C, 14.97% G and 24.87% T) with an overall A + T content of 53.93% ("light strand"). Phylogenetic analysis indicated that P. fulvifrons is closely related to the congeneric vinous-throated parrotbill (P. webbianus).


Assuntos
Genes Mitocondriais , Genoma Mitocondrial , Passeriformes/genética , Filogenia , Animais , Composição de Bases , Sequência de Bases , Códon , DNA Mitocondrial , Tamanho do Genoma , Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Análise de Sequência de DNA
6.
Trop Life Sci Res ; 27(2): 127-34, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27688856

RESUMO

The house sparrow (Passer domesticus) is a widely distributed bird species found throughout the world. Being a species which has close association with humans, they chiefly nest on man-made structures. Here we describe the materials used by the house sparrow for making nests along an urban to rural gradient. For the current study, we selected the Coimbatore to Anaikatty road (State Highway-164), a 27 km inter-state highway, which traverses along an urban core to rural outstretch of Coimbatore. Of the 30 nests observed, 15 nests were from the rural, 8 were from the suburban, and 7 were from the urban areas. The nests had two distinct layers, specifically the structural layer and the inner lining. In the current study, we identified 11 plant species, 2 types of animal matter, and 6 types of anthropogenic matter, including plastic pieces and fine rope. The amount of anthropogenic materials in the nest formation varied along the gradients. The usage of anthropogenic materials was high in urban areas (p<0.05) whereas it did not differ at the sub-urban regions (p>0.05). A gradual decrease in the usage of plant matter towards the urban area was noticed (p<0.05). This study explicitly documents the links between nest material usage along an urban to rural gradient, in a human associated bird.

7.
Mol Phylogenet Evol ; 56(2): 840-7, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20363341

RESUMO

The nuclear gene (c-mos) and mitochondrial genes (CYT B and ND2) sequences, representing 44 phasianid species and 26 genera (mainly distributed in China), were used to study the phylogeny of the genus Perdix, which comprises three partridge species. Maximum parsimony and Bayesian methods were employed, and the analysis of mitochondrial sequence data and the combined dataset showed that Perdix is specifically related either to typical pheasants or to Ithaginis. Phylogenetic trees also indicated that: (1) Perdix is monophyletic; (2) the Tibetan partridge (Perdix hodgsoniae) has been consistently placed as basal to all other Perdix, and the Daurian partridge (Perdix dauuricae) is placed sister to gray partridge (Perdix perdix); (3) the Daurian partridge subspecies przewalskii and Tibetan partridge subspecies hodgsoniae are basal to other subspecies in their species clade, respectively. Speciation in Perdix was likely promoted by the late Pliocene/early Pleistocene intensive uplift of the Tibetan Plateau and by Pleistocene glaciations.


Assuntos
Evolução Molecular , Galliformes/genética , Especiação Genética , Filogenia , Animais , Teorema de Bayes , Núcleo Celular/genética , China , DNA Mitocondrial/genética , Galliformes/classificação , Genes Mitocondriais , Análise de Sequência de DNA , Especificidade da Espécie
8.
Mol Phylogenet Evol ; 53(2): 378-83, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19591951

RESUMO

The taxonomic status of some genera within the Phasianidae remains controversial. To demonstrate the phylogenetic relationships of four endemic genera (Tetraophasis, Ithaginis, Crossoptilon and Chrysolophus) and other 11 genera of Phasianidae in China, a total of 1070 nucleotides of mitochondrial DNA (mtDNA) control-region genes were sequenced. There are 376 variable sites including 345 parsimony sites. The genetic distance ranged from 0.067 (Chrysolophus and Phasianus) to 0.181 (Perdix and Bambusicola) among the 15 genera. Maximum likelihood method was used to construct a phylogenetic tree, which grouped all the genera into two deeply divergent clades. Perdix was shown to be a non-partridge genus. Alternatively, it appears ancestral to either partridges or pheasants. The sibling taxa of the four endemic genera were Lophophorus, Tragopan, Lophura and Phasianus, respectively. Calibrated rates of molecular evolution suggested that the divergence time between the four genera and related taxa was 4.00-5.00 million years ago, corresponding to the Pliocene. Considering their molecular phylogenetics, fossil and geographical distribution patterns, the four endemic genera might have originated in the southwestern mountains in China.


Assuntos
Evolução Molecular , Galliformes/genética , Filogenia , Animais , China , DNA Mitocondrial/genética , Galliformes/classificação , Análise de Sequência de DNA
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