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1.
Syst Biol ; 73(2): 279-289, 2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-38157277

RESUMO

Different genomic regions may reflect conflicting phylogenetic topologies primarily due to incomplete lineage sorting and/or gene flow. Genomic data are necessary to reconstruct the true species tree and explore potential causes of phylogenetic conflict. Here, we investigate the phylogenetic relationships of 4 Emberiza species (Aves: Emberizidae) and discuss the potential causes of the observed mitochondrial non-monophyly of Emberiza godlewskii (Godlewski's bunting) using phylogenomic analyses based on whole genome resequencing data from 41 birds. Analyses based on both the whole mitochondrial genome and ~39 kilobases from the non-recombining W chromosome reveal sister relationships between each the northern and southern populations of E. godlewskii with E. cioides and E. cia, respectively. In contrast, the monophyly of E. godlewskii is reflected by the phylogenetic signal of autosomal and Z chromosomal sequence data as well as demographic inference analyses, which-in combination-support the following tree topology: ([{E. godlewskii, E. cia}, E. cioides], E. jankowskii). Using D-statistics, we detected multiple gene flow events among different lineages, indicating pervasive introgressive hybridization within this clade. Introgression from an unsampled lineage that is sister to E. cioides or introgression from an unsampled mitochondrial + W chromosomal lineage of E. cioides into northern E. godlewskii may explain the phylogenetic conflict between the species tree estimated from genome-wide data versus mtDNA/W tree topologies. These results underscore the importance of using genomic data for phylogenetic reconstruction and species delimitation.


Assuntos
Passeriformes , Filogenia , Animais , Passeriformes/genética , Passeriformes/classificação , Herança Materna/genética , Genoma Mitocondrial/genética , Fluxo Gênico
2.
Mol Biol Evol ; 40(3)2023 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-36869752

RESUMO

Song is considered to play an important role in the maintenance of prezygotic reproductive isolation between closely related songbird species. Therefore, song mixing in a contact zone between closely related species is often considered as evidence of hybridization. The Sichuan Leaf Warbler Phylloscopus forresti and the Gansu Leaf Warbler Phylloscopus kansuensis, which diverged 2 million years ago, have formed a contact zone in the south of the Gansu Province of China, where mixed songs have been observed. In this study, we investigated the potential causes and consequences of song mixing by integrating bioacoustic, morphological, mitochondrial, and genomic data with field ecological observations. We found that the two species display no apparent morphological differences, whereas their songs differ dramatically. We demonstrated that ∼11% of the males in the contact zone sang mixed songs. Two males singing mixed song were genotyped, and both were found to be P. kansuensis. Despite the presence of mixed singers, population genomic analyses detected no signs of recent gene flow between the two species, although two possible cases of mitochondrial introgression were identified. We conclude that the rather limited song mixing does not lead to, or result from, hybridization, and hence does not result in the breakdown of reproductive barriers between these cryptic species.


Assuntos
Passeriformes , Aves Canoras , Masculino , Animais , Aves Canoras/genética , Fluxo Gênico , Passeriformes/genética , Isolamento Reprodutivo , Genômica , Vocalização Animal
3.
Mol Biol Evol ; 40(1)2023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36562771

RESUMO

Rare and geographically restricted species may be vulnerable to genetic effects from inbreeding depression in small populations or from genetic swamping through hybridization with common species, but a third possibility is that selective gene flow can restore fitness (genetic rescue). Climate-sensitive pikas (Ochotona spp.) of the Qinghai-Tibetan Plateau (QHTP) and its vicinity have been reduced to residual populations through the movement of climatic zones during the Pleistocene and recent anthropogenic disturbance, whereas the plateau pika (O. curzoniae) remains common. Population-level whole-genome sequencing (n = 142) of six closely related species in the subgenus Ochotona revealed several phases of ancient introgression, lineage replacement, and bidirectional introgression. The strength of gene flow was the greatest from the dominant O. curzoniae to ecologically distinct species in areas peripheral to the QHTP. Genetic analyses were consistent with environmental reconstructions of past population movements. Recurrent periods of introgression throughout the Pleistocene revealed an increase in genetic variation at first but subsequent loss of genetic variation in later phases. Enhanced dispersion of introgressed genomic regions apparently contributed to demographic recovery in three peripheral species that underwent range shifts following climate oscillations on the QHTP, although it failed to drive recovery of northeastern O. dauurica and geographically isolated O. sikimaria. Our findings highlight differences in timescale and environmental background to determine the consequence of hybridization and the unique role of the QHTP in conserving key evolutionary processes of sky island species.


Assuntos
Lagomorpha , Animais , Lagomorpha/genética , Evolução Biológica , Hibridização Genética , Genômica , Demografia
4.
BMC Cardiovasc Disord ; 24(1): 117, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38373881

RESUMO

BACKGROUND: To determine the prognostic value of cumulative calcification score of coronary artery calcification (CAC), thoracic aortic calcification (TAC) and aortic valve calcification (AVC) in acute ST segment elevation myocardial infarction (STEMI) patients. METHODS: This was a retrospective, single-center cohort study. A total of 332 STEMI patients who received primary percutaneous coronary intervention (PPCI) were enrolled in this study between January 2010 to October 2018. We assessed the calcification in the left anterior descending branch (LAD), left circumflex branch (LCX), right coronary artery (RCA), thoracic aorta, and aortic valve. Calcification of each part was counted as 1 point, and the cumulative calcification score was calculated as the sum of all points. The primary endpoint was all-cause mortality. Multivariate Cox proportional hazards models were used to determine association of cumulative calcification score with end points. The performance of the score was evaluated by receiver operating characteristic (ROC) curve analysis and absolute net reclassification improvement (NRI), compared with the Global Registry of Acute Coronary Events (GRACE) risk score. RESULTS: The overall population's calcification score was 2.0 ± 1.6. During a mean follow-up time of 69.8 ± 29.3 months, the all-cause mortality rate was 12.1%. Kaplan-Meier curve showed that the score was significantly associated with mortality (log-rank p < 0.001). The multivariable Cox proportional hazard analyses showed that a calcification score of 4-5 was independently associated with all-cause death in STEMI patients [hazard ratio (HR) = 2.32, 95% confidence interval (CI): 1.01-5.31, p = 0.046]. The area under the ROC curve (AUC) of the calcification score was 0.67 (95% CI: 0.61-0.72), and the AUC of the GRACE score was 0.80 (95% CI: 0.75-0.84). There was no statistical difference in the predictive value between both scores for 3-year mortality in STEMI patients after PPCI (p = 0.06). Based on the NRI analysis, the calcification score showed better risk classification compared with the GRACE score (absolute NRI = 6.63%, P = 0.027). CONCLUSION: The cumulative calcification score is independently associated with the long-term prognosis of STEMI patients after PPCI.


Assuntos
Doença da Artéria Coronariana , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Estudos de Coortes , Estudos Retrospectivos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Fatores de Risco , Prognóstico , Arritmias Cardíacas/complicações , Intervenção Coronária Percutânea/efeitos adversos , Medição de Risco
5.
Proc Natl Acad Sci U S A ; 118(50)2021 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-34873033

RESUMO

Parallel evolution can be expected among closely related taxa exposed to similar selective pressures. However, parallelism is typically stronger at the phenotypic level, while genetic solutions to achieve these phenotypic similarities may differ. For polygenic traits, the availability of standing genetic variation (i.e., heterozygosity) may influence such genetic nonparallelism. Here, we examine the extent to which high-elevation adaptation is parallel-and whether the level of parallelism is affected by heterozygosity-by analyzing genomes of 19 Paridae species distributed across East Asia with a dramatic east-west elevation gradient. We find that western highlands endemic parids have consistently lower levels of heterozygosity-likely the result of late-Pleistocene demographic contraction-than do parids found exclusively in eastern lowlands, which remained unglaciated during the late Pleistocene. Three widespread species (east to west) have high levels of heterozygosity similar to that observed in eastern species, although their western populations are less variable than eastern ones. Comparing genomic responses to extreme environments of the Qinghai-Tibet Plateau, we find that the most differentiated genomic regions between each high-elevation taxon and its low-elevation relative are significantly enriched for genes potentially related to the oxygen transport cascade and/or thermogenesis. Despite no parallelism at particular genes, high similarity in gene function is found among comparisons. Furthermore, parallelism is not higher in more heterozygous widespread parids than in highland endemics. Thus, in East Asian parids, parallel functional response to extreme elevation appears to rely on different genes, with differences in heterozygosity having no effect on the degree of genetic parallelism.


Assuntos
Altitude , Distribuição Animal , Mudança Climática , Genômica , Aves Canoras/genética , Aves Canoras/fisiologia , Animais , Evolução Biológica , Ásia Oriental , Variação Genética , Genoma
6.
Mol Ecol ; 32(2): 381-392, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36326561

RESUMO

The seasonal migration of birds is a fascinating natural wonder. Avian migratory behaviour changes are common and are probably a polygenic process as avian migration is governed by multiple correlated components with a variable genetic basis. However, the genetic and phenotypic changes involving migration changes are poorly studied. Using one annotated near-chromosomal level de novo genome assembly, 50 resequenced genomes, hundreds of morphometric data and species distribution information, we investigated population structure and genomic and phenotypic differences associated with differences in migratory behaviour in a songbird species, Yellow-throated Bunting Emberiza elegans (Aves: Emberizidae). Population genomic analyses reveal extensive gene flow between the southern resident and the northern migratory populations of this species. The hand-wing index is significantly lower in the resident populations than in the migratory populations, indicating reduced flight efficiency of the resident populations. Here, we discuss the possibility that nonmigratory populations may have originated from migratory populations though migration loss. We further infer that the alterations of genes related to energy metabolism, nervous system and circadian rhythm may have played major roles in regulating migration change. Our study sheds light on phenotypic and polygenic changes involving migration change.


Assuntos
Passeriformes , Aves Canoras , Animais , Aves Canoras/genética , Fotoperíodo , Migração Animal/fisiologia , Estações do Ano , Genômica
7.
PLoS Genet ; 16(12): e1009270, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33370292

RESUMO

Skeletal muscle plays a central role in regulating glucose uptake and body metabolism; however, highland hypoxia is a severe challenge to aerobic metabolism in small endotherms. Therefore, understanding the physiological and genetic convergence of muscle hypoxia tolerance has a potential broad range of medical implications. Here we report and experimentally validate a common physiological mechanism across multiple high-altitude songbirds that improvement in insulin sensitivity contributes to glucose homeostasis, low oxygen consumption, and relative activity, and thus increases body weight. By contrast, low-altitude songbirds exhibit muscle loss, glucose intolerance, and increase energy expenditures under hypoxia. This adaptive mechanism is attributable to convergent missense mutations in the BNIP3L gene, and METTL8 gene that activates MEF2C expression in highlanders, which in turn increases hypoxia tolerance. Together, our findings from wild high-altitude songbirds suggest convergent physiological and genetic mechanisms of skeletal muscle in hypoxia resistance, which highlights the potentially medical implications of hypoxia-related metabolic diseases.


Assuntos
Adaptação Fisiológica , Altitude , Evolução Molecular , Consumo de Oxigênio , Transcriptoma , Animais , Peso Corporal , Tentilhões , Glucose/metabolismo , Homeostase , Insulina/metabolismo , Músculo Esquelético/metabolismo
8.
Syst Biol ; 70(5): 961-975, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-33787929

RESUMO

Phylogenetic trees based on genome-wide sequence data may not always represent the true evolutionary history for a variety of reasons. One process that can lead to incorrect reconstruction of species phylogenies is gene flow, especially if interspecific gene flow has affected large parts of the genome. We investigated phylogenetic relationships within a clade comprising eight species of passerine birds (Phylloscopidae, Phylloscopus, leaf warblers) using one de novo genome assembly and 78 resequenced genomes. On the basis of hypothesis-exclusion trials based on D-statistics, phylogenetic network analysis, and demographic inference analysis, we identified ancient gene flow affecting large parts of the genome between one species and the ancestral lineage of a sister species pair. This ancient gene flow consistently caused erroneous reconstruction of the phylogeny when using large amounts of genome-wide sequence data. In contrast, the true relationships were captured when smaller parts of the genome were analyzed, showing that the "winner-takes-all democratic majority tree" is not necessarily the true species tree. Under this condition, smaller amounts of data may sometimes avoid the effects of gene flow due to stochastic sampling, as hidden reticulation histories are more likely to emerge from the use of larger data sets, especially whole-genome data sets. In addition, we also found that genomic regions affected by ancient gene flow generally exhibited higher genomic differentiation but a lower recombination rate and nucleotide diversity. Our study highlights the importance of considering reticulation in phylogenetic reconstructions in the genomic era.[Bifurcation; introgression; recombination; reticulation; Phylloscopus.].


Assuntos
Fluxo Gênico , Aves Canoras , Animais , Genoma/genética , Genômica , Filogenia , Aves Canoras/genética
9.
Proc Natl Acad Sci U S A ; 116(24): 11851-11856, 2019 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-31127049

RESUMO

High-altitude environments present strong stresses for living organisms, which have driven striking phenotypic and genetic adaptations. While previous studies have revealed multiple genetic adaptations in high-altitude species, how evolutionary history (i.e., phylogenetic background) contributes to similarity in genetic adaptations to high-altitude environments is largely unknown, in particular in a group of birds. We explored this in 3 high-altitude passerine birds from the Qinghai-Tibet Plateau and their low-altitude relatives in lowland eastern China. We generated transcriptomic data for 5 tissues across these species and compared sequence changes and expression shifts between high- and low-altitude pairs. Sequence comparison revealed that similarity in all 3 high-altitude species was high for genes under positive selection (218 genes) but low in amino acid substitutions (only 4 genes sharing identical amino acid substitutions). Expression profiles for all genes identified a tissue-specific expression pattern (i.e., all species clustered by tissue). By contrast, an altitude-related pattern was observed in genes differentially expressed between all 3 species pairs and genes associated with altitude, suggesting that the high-altitude environment may drive similar expression shifts in the 3 high-altitude species. Gene expression level, gene connectivity, and the interactions of these 2 factors with altitude were correlated with evolutionary rates. Our results provide evidence for how gene sequence changes and expression shifts work in a concerted way in a group of high-altitude birds, leading to similar evolution routes in response to high-altitude environmental stresses.

10.
Mol Biol Evol ; 37(10): 2983-2988, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32592485

RESUMO

The Ground Tit (Pseudopodoces humilis) has lived on the Qinghai-Tibet Plateau for ∼5.7 My and has the highest altitudinal distribution among all parids. This species has evolved an elongated beak in response to long-term selection imposed by ground-foraging and cavity-nesting habits, yet the genetic basis for beak elongation remains unknown. Here, we perform genome-wide analyses across 14 parid species and identify 25 highly divergent genomic regions that are significantly associated with beak length, finding seven candidate genes involved in bone morphogenesis and remolding. Neutrality tests indicate that a model allowing for a selective sweep in the highly conserved COL27A1 gene best explains variation in beak length. We also identify two nonsynonymous fixed mutations in the collagen domain that are predicted to be functionally deleterious yet may have facilitated beak elongation. Our study provides evidence of adaptive alleles in COL27A1 with major effects on beak elongation of Ps. humilis.


Assuntos
Bico/anatomia & histologia , Evolução Biológica , Colágenos Fibrilares/genética , Aves Canoras/genética , Adaptação Biológica , Substituição de Aminoácidos , Animais , Genômica , Filogeografia , Seleção Genética , Aves Canoras/anatomia & histologia
11.
Curr Genomics ; 22(7): 496-511, 2021 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-35386431

RESUMO

Genomic data are important for understanding the origin and evolution of traits. Under the context of rapidly developing of sequencing technologies and more widely available genome sequences, researchers are able to study evolutionary mechanisms of traits via comparative genomic methods. Compared with other vertebrates, bird genomes are relatively small and exhibit conserved synteny with few repetitive elements, which makes them suitable for evolutionary studies. Increasing genomic progress has been reported on the evolution of powered flight, body size variation, beak morphology, plumage colouration, high-elevation colonization, migration, and vocalization. By summarizing previous studies, we demonstrate the genetic bases of trait evolution, highlighting the roles of small-scale sequence variation, genomic structural variation, and changes in gene interaction networks. We suggest that future studies should focus on improving the quality of reference genomes, exploring the evolution of regulatory elements and networks, and combining genomic data with morphological, ecological, behavioural, and developmental biology data.

12.
Proc Natl Acad Sci U S A ; 115(8): 1865-1870, 2018 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-29432191

RESUMO

When different species experience similar selection pressures, the probability of evolving similar adaptive solutions may be influenced by legacies of evolutionary history, such as lineage-specific changes in genetic background. Here we test for adaptive convergence in hemoglobin (Hb) function among high-altitude passerine birds that are native to the Qinghai-Tibet Plateau, and we examine whether convergent increases in Hb-O2 affinity have a similar molecular basis in different species. We documented that high-altitude parid and aegithalid species from the Qinghai-Tibet Plateau have evolved derived increases in Hb-O2 affinity in comparison with their closest lowland relatives in East Asia. However, convergent increases in Hb-O2 affinity and convergence in underlying functional mechanisms were seldom attributable to the same amino acid substitutions in different species. Using ancestral protein resurrection and site-directed mutagenesis, we experimentally confirmed two cases in which parallel substitutions contributed to convergent increases in Hb-O2 affinity in codistributed high-altitude species. In one case involving the ground tit (Parus humilis) and gray-crested tit (Lophophanes dichrous), parallel amino acid replacements with affinity-enhancing effects were attributable to nonsynonymous substitutions at a CpG dinucleotide, suggesting a possible role for mutation bias in promoting recurrent changes at the same site. Overall, most altitude-related changes in Hb function were caused by divergent amino acid substitutions, and a select few were caused by parallel substitutions that produced similar phenotypic effects on the divergent genetic backgrounds of different species.


Assuntos
Adaptação Fisiológica/genética , Altitude , Hemoglobinas/fisiologia , Passeriformes/genética , Passeriformes/fisiologia , Distribuição Animal , Animais , Evolução Molecular , Hemoglobinas/genética , Modelos Moleculares , Passeriformes/sangue , Conformação Proteica , Isoformas de Proteínas , Tibet
13.
Mol Biol Evol ; 36(11): 2375-2386, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31364717

RESUMO

In the absence of nuclear-genomic differentiation between two populations, deep mitochondrial divergence (DMD) is a form of mito-nuclear discordance. Such instances of DMD are rare and might variably be explained by unusual cases of female-linked selection, by male-biased dispersal, by "speciation reversal" or by mitochondrial capture through genetic introgression. Here, we analyze DMD in an Asian Phylloscopus leaf warbler (Aves: Phylloscopidae) complex. Bioacoustic, morphological, and genomic data demonstrate close similarity between the taxa affinis and occisinensis, even though DMD previously led to their classification as two distinct species. Using population genomic and comparative genomic methods on 45 whole genomes, including historical reconstructions of effective population size, genomic peaks of differentiation and genomic linkage, we infer that the form affinis is likely the product of a westward expansion in which it replaced a now-extinct congener that was the donor of its mtDNA and small portions of its nuclear genome. This study provides strong evidence of "ghost introgression" as the cause of DMD, and we suggest that "ghost introgression" may be a widely overlooked phenomenon in nature.

14.
J Cell Biochem ; 119(10): 8271-8281, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29923343

RESUMO

Inhibin-α, a member of the transforming growth factor (TGF-ß) superfamily, has been involved in bone turnover during the menopausal transition via endocrine effects, and it was previously reported that inhibins may antagonize the function of BMPs. Certainly, one of the most important functions of BMPs is to induce osteogenic differentiation. BMP9 as one of the most potent BMPs to induce osteogenic differentiation has gotten more and more attentions. Nonetheless, the effects of inhibin-α on osteogenesis remain unknown. Besides, mesenchymal stem cells (MSCs) with the ability to differentiate into multiple mesenchymal lineages, including osteoblasts, adipocyte, chondrocytes, and myoblasts in vitro, have become the promising seed cells for bone tissue engineering. Here, we investigated the role of inhibin-α on BMP9-induced osteogenic differentiation in MSCs and tried to discover the mechanism underlying this process. We found inhibin-α apparently reduced the classical osteogenic markers and the ectopic bone formation induced by BMP9. In addition, the ratio of OPG to RANKL is declined also in the presence of inhibin-α. For mechanism, we found that exogenous expression of inhibin-α inhibits BMP9-induced osteogenic differentiation through blocking BMP/Smad signal transduction and activating NF-κB signal which is repressed by BMP9. Thus, our findings indicated that inhibin-α has a negative effect on BMP9-induced osteogenic differentiation in MSCs, which may provide a novel insight into the regulation of skeletal development and new strategy for bone tissue engineering.


Assuntos
Fatores de Diferenciação de Crescimento/genética , Inibinas/genética , Células-Tronco Mesenquimais/metabolismo , NF-kappa B/genética , Osteogênese/genética , Proteína Smad6/genética , Proteína Smad7/genética , Animais , Osso e Ossos/citologia , Osso e Ossos/metabolismo , Diferenciação Celular , Linhagem Celular , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Feminino , Regulação da Expressão Gênica , Fator 2 de Diferenciação de Crescimento , Fatores de Diferenciação de Crescimento/metabolismo , Células HEK293 , Humanos , Inibinas/metabolismo , Células-Tronco Mesenquimais/citologia , Camundongos , Camundongos Nus , NF-kappa B/metabolismo , Osteoblastos/citologia , Osteoblastos/metabolismo , Osteoprotegerina/genética , Osteoprotegerina/metabolismo , Ligante RANK/genética , Ligante RANK/metabolismo , Ratos , Transdução de Sinais , Proteína Smad6/metabolismo , Proteína Smad7/metabolismo , Transfecção
15.
Cell Physiol Biochem ; 46(2): 546-560, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29617681

RESUMO

BACKGROUND/AIMS: Genomic adaptations to high altitudes have been well studied in the last several years; however, the roles of microRNAs (miRNAs), which are essential modulators of a variety of genes and key cellular processes, have rarely been explored. Here, we explored the interactions between miRNAs and their target genes as an adaptation to high altitude in an avian species, the great tit (Parus major), which is widely distributed across the Eurasian continent at altitudes between 4500 m and sea level. Because the MAPK signaling pathway plays a crucial role in the hypoxia response in the great tit, we chose MAPK1 as a target candidate gene. METHODS: We established a great tit embryonic fibroblast line and subsequently studied the relationship between miRNA-19b-3p and MAPK1 in normoxia and hypoxia groups. Meanwhile, the great tit embryonic fibroblasts (GEFs) were treated or transfected with miR-19b-3p mimics, inhibitors, or si-MAPK1, and their proliferation was subsequently assessed using the MTT assay. The expression of the miRNAs and MAPK1 was measured by real-time PCR and Western blotting. RESULTS: We identified 14 miRNAs in the cardiac tissues of great tits that are related to hypoxia adaptation. MAPK1 binds only to miR-19b-3p of the 14 miRNAs predicted by both TargetScan and miRanda software. Specifically, we validated the computational prediction of miR-19b-3p binding to the 3'UTR of MAPK1 using a luciferase reporter assay. Our results show that miR-19b-3p promotes GEFs proliferation and up-regulates MAPK1 expression. Moreover, miR-19b-3p mimics and MAPK1 knockdown induce GEFs apoptosis and regulate the cell cycle under hypoxic conditions. CONCLUSIONS: Our study is the first to describe an important miRNA-mediated regulatory mechanism of high altitude adaptation in a non-model wild songbird and highlights the importance of studies on miRNA-mediated mechanisms of hypoxic adaptations in other animals.


Assuntos
Proteínas Aviárias/metabolismo , Hipóxia Celular , MicroRNAs/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Regiões 3' não Traduzidas , Animais , Antagomirs , Apoptose , Proteínas Aviárias/antagonistas & inibidores , Proteínas Aviárias/genética , Sequência de Bases , Pontos de Checagem do Ciclo Celular , Linhagem Celular , Proliferação de Células , Embrião não Mamífero/citologia , Fibroblastos/citologia , Fibroblastos/metabolismo , Redes Reguladoras de Genes , Hibridização in Situ Fluorescente , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 1 Ativada por Mitógeno/genética , Passeriformes/genética , Passeriformes/metabolismo , Interferência de RNA , RNA Interferente Pequeno , Alinhamento de Sequência , Análise de Sequência de RNA
16.
Mol Ecol ; 26(23): 6654-6665, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29055167

RESUMO

Patterns of heterogeneous genomic differentiation have been well documented between closely related species, with some highly differentiated genomic regions ("genomic differentiation islands") spread throughout the genome. Differential levels of gene flow are proposed to account for this pattern, as genomic differentiation islands are suggested to be resistant to gene flow. Recent studies have also suggested that genomic differentiation islands could be explained by linked selection acting on genomic regions with low recombination rates. Here, we investigate genomic differentiation and gene-flow patterns for autosomes using RAD-seq data between two closely related species of long-tailed tits (Aegithalos bonvaloti and A. fuliginosus) in both allopatric and contact zone populations. The results confirm recent or ongoing gene flow between these two species. However, there is little evidence that the genomic regions that were found to be highly differentiated between the contact zone populations are resistant to gene flow, suggesting that differential levels of gene flow is not the cause of the heterogeneous genomic differentiation. Linked selection may be the cause of genomic differentiation islands between the allopatric populations with no or very limited gene flow, but this could not account for the heterogeneous genomic differentiation between the contact zone populations, which show evidence of recent or ongoing gene flow.


Assuntos
Fluxo Gênico , Genética Populacional , Passeriformes/genética , Animais , China , Genoma , Desequilíbrio de Ligação , Filogenia
17.
Front Zool ; 14: 58, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29299037

RESUMO

BACKGROUND: Beak morphology exhibits considerable adaptive plasticity in birds, which results in highly varied or specialized forms in response to variations in ecology and life history. As the only parid species endemic to the Qinghai-Tibet Plateau, the Ground Tit (Parus humilis) has evolved a distinctly long and curved beak from other parids. An integration of morphometrics, phylogenetics, transcriptomics and embryology allows us to address the evolutionary and developmental mechanisms of the adaptive beak structure observed in the Ground Tit. RESULTS: A morphometric approach quantified that the Ground Tit has a comparatively longer and more decurved upper beaks than other parids. We estimated that the ancestor of the Ground Tit likely had a short straight upper beak similar to most current recognized parid species using an ancestral state reconstruction. This morphological specialization is considered an adaptation to its ground-oriented behavior on the high plateau. To identify genetic mechanisms behind this adaptive change, a comparative transcriptomic analysis was applied between the Ground Tit and its closely related species, the Great Tit (Parus major). We detected that 623 genes were significantly differentially expressed in embryonic upper beaks between the two species, 17 of which were functionally annotated to correlate with bone development and morphogenesis, although genes related to bone development were not found to undergo accelerated evolution in the Ground Tit. RT-qPCR validation confirmed differential expression of five out of eight genes that were selected from the 17 genes. Subsequent functional assays in chicken embryos demonstrated that two of these genes, FGF13 and ITGB3, may affect beak morphology by modulating levels of osteoblasts and osteoclasts. CONCLUSIONS: Our results provide preliminary evidence that development of the long decurved beak of the Ground Tit is likely regulated by transcriptional activities of multiple genes coordinating osteoblasts and osteoclasts. The integration of multiple approaches employed here sheds light on ecological and genetic mechanisms in the evolution of avian morphology.

18.
Med Princ Pract ; 23(1): 89-91, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24008657

RESUMO

OBJECTIVE: To report a case of rectal cancer in a patient with Peutz-Jeghers syndrome (PJS). CLINICAL PRESENTATION AND INTERVENTION: A 20-year-old woman with intermittent bloody stool of 4 months was admitted for examination. Gastroendoscopy revealed multiple polyps involving the stomach, small intestine, colon and a rectal adenocarcinoma. A diagnosis of PJS was made based on intestinal polyps with characteristic pathology and melanotic macules on the lips. After surgery and chemotherapy upon follow-up at 8 months, the patient did not have any signs of recurrence. CONCLUSION: This case showed that rectal carcinoma should be considered for young patients with PJS.


Assuntos
Síndrome de Peutz-Jeghers/epidemiologia , Neoplasias Retais/epidemiologia , Adulto , Diagnóstico Diferencial , Feminino , Humanos , Síndrome de Peutz-Jeghers/diagnóstico , Síndrome de Peutz-Jeghers/terapia , Neoplasias Retais/terapia
19.
J Thorac Dis ; 16(8): 5314-5322, 2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39268116

RESUMO

Background: The effects of the drug-coated balloon (DCB)-only strategy in the treatment of chronic total occlusion (CTO) coronary lesions remain controversial. Patients who underwent an in-stent restenosis (ISR) CTO percutaneous coronary intervention (PCI) had a significantly poorer prognosis than those who underwent a de novo CTO PCI. This retrospective analysis evaluated the efficacy and safety of the DCB-only strategy in the treatment of CTO lesions, and the factors associated with adverse events in the patients. Methods: Patients with CTO lesions who were treated with the DCB-only strategy from 1 January 2016 to 1 May 2021 were retrospectively enrolled in this study. The patients were stratified into the ISR and de novo (primary) groups. All the patients were re-admitted to the hospital and underwent clinical and/or angiographic follow-up. Results: Of the 68 patients with CTO lesions, 38 (55.9%) were categorized as having ISR, and 30 (44.1%) were categorized as having de novo lesions. The outcomes measured included target lesion revascularization (TLR), lumen gain after intervention, and late lumen loss (LLL). After an average follow-up period of 16 months, a total of 15 patients experienced target lesion failure (13 in the ISR group and 2 in the de novo group). The rate of major adverse cardiac events (MACEs) was significantly lower in the de novo group than the ISR group (10% vs. 39%, P=0.004). There was a significant difference in LLL between the two groups, with the de novo group showing a decrease (-0.04±0.83 mm) and the ISR group showing an increase (0.97±1.45 mm) (P=0.03). The univariable Cox proportional hazard analyses revealed that the incidence of TLR was independently associated with the stenosis type (either ISR or de novo lesions) [odds ratio (OR): 7.28; 95% confidence interval (CI): 1.494-35.464; P=0.01]. Male gender (OR: 3.726; 95% CI: 1.014-12.818; P=0.03) and body mass index (BMI) (OR: 1.246; 95% CI: 1.022-1.518, P=0.03) were also associated with the incidence of TLR. However, after adjusting for the variables of age, gender, and BMI, no significant association was found between MACE occurrence and ISR (OR: 4.156, 95% CI: 0.734-23.522; P=0.11). Conclusions: Treatment using the DCB-only strategy was found to be beneficial for patients suffering from CTO coronary lesions, especially those presenting with de novo lesions.

20.
Biology (Basel) ; 13(8)2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39194581

RESUMO

A secondary contact zone (SCZ) is an area where incipient species or divergent populations may meet, mate, and hybridize. Due to the diverse patterns of interspecific hybridization, SCZs function as field labs for illuminating the on-going evolutionary processes of speciation and the establishment of reproductive isolation. Interspecific hybridization is widely present in avian populations, making them an ideal system for SCZ studies. This review exhaustively summarizes the variations in unique traits within avian SCZs (vocalization, plumage, beak, and migratory traits) and the various movement patterns of SCZs observed in previous publications. It also highlights several potential future research directions in the genomic era, such as the relationship between phenotypic and genomic differentiation in SCZs, the genomic basis of trait differentiation, SCZs shared by multiple species, and accurate predictive models for forecasting future movements under climate change and human disturbances. This review aims to provide a more comprehensive understanding of speciation processes and offers a theoretical foundation for species conservation.

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