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1.
Nat Commun ; 15(1): 2693, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38538607

RESUMO

Enhancing the device electroluminescence quantum efficiency (EQEEL) is a critical factor in mitigating non-radiative voltage losses (VNR) and further improving the performance of organic solar cells (OSCs). While the common understanding attributes EQEEL in OSCs to the dynamics of charge transfer (CT) states, persistent efforts to manipulate these decay dynamics have yielded limited results, with the EQEEL of high-efficiency OSCs typically remaining below 10-2%. This value is considerably lower than that observed in high efficiency inorganic photovoltaic devices. Here, we report that EQEEL is also influenced by the dissociation rate constant of singlet states (kDS). Importantly, in contrast to the traditional belief that advocates maximizing kDS for superior photovoltaic quantum efficiency (EQEPV), a controlled reduction in kDS is shown to enhance EQEEL without compromising EQEPV. Consequently, a promising experimental approach to address the VNR challenge is proposed, resulting in a significant improvement in the performance of OSCs.

2.
Patterns (N Y) ; 5(3): 100915, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38487801

RESUMO

Understanding tissue architecture and niche-specific microenvironments in spatially resolved transcriptomics (SRT) requires in situ annotation and labeling of cells. Effective spatial visualization of these data demands appropriate colorization of numerous cell types. However, current colorization frameworks often inadequately account for the spatial relationships between cell types. This results in perceptual ambiguity in neighboring cells of biological distinct types, particularly in complex environments such as brain or tumor. To address this, we introduce Spaco, a potent tool for spatially aware colorization. Spaco utilizes the Degree of Interlacement metric to construct a weighted graph that evaluates the spatial relationships among different cell types, refining color assignments. Furthermore, Spaco incorporates an adaptive palette selection approach to amplify chromatic distinctions. When benchmarked on four diverse datasets, Spaco outperforms existing solutions, capturing complex spatial relationships and boosting visual clarity. Spaco ensures broad accessibility by accommodating color vision deficiency and offering open-accessible code in both Python and R.

3.
Am J Prev Cardiol ; 17: 100633, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38380078

RESUMO

Background: Low physical activity is a major risk factor for cardiovascular diseases (CVDs). This study aimed to estimate the global, regional, national, and sex-age-specific burden of CVDs attributed to low physical activity from 1990 to 2019. Methods: We leveraged data from the Global Burden of Disease Study 2019 to compute the number of fatalities, disability-adjusted life years (DALYs), age-adjusted mortality rates (ASMR), and age-adjusted DALY rates (ASDR) attributed to CVDs resulting from low physical activity. Furthermore, we scrutinized the trends and correlations of these metrics in connection with the socio-demographic index (SDI) across 21 regions and 204 countries and territories. Results: The global deaths and DALYs due to CVDs caused by low physical activity increased from 371,042.96 [95 % UI: 147,621.82-740,490] and 6,282,524.95 [95 % UI: 2,334,970.61-13,255,090.08] in 1990 to 639,174.92 [95 % UI: 272,011.34-1,216,528.4] and 9,996,080.17 [95 % UI: 4,130,111.16-20,323,339.89] in 2019, respectively. The corresponding ASMR and ASDR decreased from 12.55 [95 % UI: 5.12-24.23] and 181.64 [95 % UI: 71.59-374.01] in 1990 to 8.6 [95 % UI: 3.68-16.28] and 127.52 [95 % UI: 53.07-256.55] in 2019, respectively. Deaths and DALYs attributed to low physical activity were initially higher in males but shifted to females after 70-74 age group. Both genders had increasing death rates, peaking at 80-84 age group. Most CVDs deaths and DALYs number are caused by ischemic heart disease. The highest burden of CVDs attributed to low physical activity was observed in North Africa and the Middle East. The lowest burden was observed in Oceania and High-income Asia Pacific. There was a distinctive 'n-shape' relationship between the regional SDI and the ASDR of CVDs attributed to low physical activity from 1990 to 2019. Conclusion: The global impact of CVDs stemming from low physical activity remains substantial and demonstrates substantial regional disparities. As individuals age, this burden becomes more prominent, particularly among females. Efficacious interventions are imperative to promote physical activity and mitigate the risk of CVDs across diverse populations and regions.

4.
ACS Appl Mater Interfaces ; 15(33): 39677-39688, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37572058

RESUMO

Developing transparent conductors to replace indium tin oxide (ITO) is a critical objective in the field of organic optoelectronics. Non-atomically doped (NAD) ZnO thin films, while currently exhibiting limited conductivity, are highly promising candidates due to their unique advantages, such as having complete transparency in both the visible and near-infrared spectral regions, solution processability, and the desired surface electronic properties. In this work, the impact of surface modification by insulating polymers on the ultraviolet-enhanced conductivity of NAD-ZnO films is investigated. It was found that polymer modifiers that are rich in amino and hydroxyl groups are effective at increasing the concentration of oxygen vacancies and the conductivity of NAD-ZnO films. The highest conductivity of over 1000 S cm-1, which is more than twice as high as the previous record for NAD-ZnO films, is achieved using polyethylenimine ethoxylated (PEIE) to modify NAD-ZnO films. Subsequently, the replacement of ITO in organic photovoltaic devices by a ZnO/PEIE electrode is realized. The ZnO/PEIE-based OPV devices that were created exhibit performances comparable to those of ITO-based devices under simulated solar illumination and performances better than those achieved with ITO-based devices under simulated indoor illumination. These results make NAD-ZnO a promising candidate for the widespread replacement of ITO in optoelectronic devices.

5.
Nat Commun ; 13(1): 3912, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35853876

RESUMO

Penguins lost the ability to fly more than 60 million years ago, subsequently evolving a hyper-specialized marine body plan. Within the framework of a genome-scale, fossil-inclusive phylogeny, we identify key geological events that shaped penguin diversification and genomic signatures consistent with widespread refugia/recolonization during major climate oscillations. We further identify a suite of genes potentially underpinning adaptations related to thermoregulation, oxygenation, diving, vision, diet, immunity and body size, which might have facilitated their remarkable secondary transition to an aquatic ecology. Our analyses indicate that penguins and their sister group (Procellariiformes) have the lowest evolutionary rates yet detected in birds. Together, these findings help improve our understanding of how penguins have transitioned to the marine environment, successfully colonizing some of the most extreme environments on Earth.


Assuntos
Spheniscidae , Animais , Evolução Biológica , Fósseis , Genoma , Genômica , Filogenia , Spheniscidae/genética
6.
ACS Appl Mater Interfaces ; 14(10): 12450-12460, 2022 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-35235287

RESUMO

Organic solar cells (OSCs) based on an inverted architecture generally have better stability compared to those based on a standard architecture. However, the photoactive area of the inverted solar cells increases under ultraviolet (UV) or solar illuminatiom because of the too-high conductivity of the UV-illuminated zinc oxide (ZnO) interlayer. This limits the potential of the inverted solar cells for industrial applications. Herein, lithium-doped ZnO (Li-ZnO) films are employed as the cathode interlayer to construct inverted OSCs. The incorporation of Li ions is found to reduce the lateral conductivity of the UV-treated ZnO films because of the presence of Li ions, preventing the high-quality-growth of ZnO nanocrystals. This addresses the problem of having too-high conductivity in the UV-treated ZnO layer, causing the increased photoactive area of inverted solar cells. The overall performance of the solar cell is shown to be higher after the incorporation of Li ions in the ZnO layer, mainly due to the increased fill factor (FF), originating from the reduced trap-assisted recombination losses. Finally, the inverted solar cells based on the Li-ZnO interlayer are demonstrated to have a much better long-term stability, as compared to those based on ZnO. This allows the ZnO-based interlayers to be used for the mass production of organic solar cell modules.

7.
Angiology ; 73(3): 265-274, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34318706

RESUMO

Many studies have shown that leukocyte cell-derived chemotaxin 2 (LECT2) is associated with metabolic disorders, which is a risk factor of arteriosclerosis. We assessed the level of LECT-2 in patients with coronary artery disease (CAD) and its severity and prognosis. We selected 666 participants who underwent coronary angiography in our hospital and included patients with non-CAD, patients with stable angina pectoris (SAP), patients with unstable angina (UA), patients with non-ST-segment elevation myocardial infarction (NSTEMI) and patients with ST-segment elevation myocardial infarction (STEMI). The serum level of LECT-2 was higher in patients with CAD than in patients with non-CAD and was an independent predictor for CAD. Subgroup analysis showed that compared with the SAP group, the UA, NSTEMI, and STEMI groups had higher serum levels of LECT-2. In addition, the level of LECT-2 was related to the SYNTAX score and SYNTAX II score. Finally, patients with acute myocardial infarction (AMI) with elevated levels of LECT-2 had a higher risk of major adverse cardiovascular events (MACEs) within 12 months than those with lower levels of LECT-2. Plasma LECT-2 levels may be useful for the diagnosis of CAD and as predictors of MACE in patients with AMI.


Assuntos
Doença da Artéria Coronariana , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Fatores Quimiotáticos , Angiografia Coronária , Estudos Transversais , Fatores de Risco de Doenças Cardíacas , Humanos
8.
Mol Biol Evol ; 39(1)2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34897511

RESUMO

Penguins (Sphenisciformes) are an iconic order of flightless, diving seabirds distributed across a large latitudinal range in the Southern Hemisphere. The extensive area over which penguins are endemic is likely to have fostered variation in pathogen pressure, which in turn will have imposed differential selective pressures on the penguin immune system. At the front line of pathogen detection and response, the Toll-like receptors (TLRs) provide insight into host evolution in the face of microbial challenge. TLRs respond to conserved pathogen-associated molecular patterns and are frequently found to be under positive selection, despite retaining specificity for defined agonist classes. We undertook a comparative immunogenetics analysis of TLRs for all penguin species and found evidence of adaptive evolution that was largely restricted to the cell surface-expressed TLRs, with evidence of positive selection at, or near, key agonist-binding sites in TLR1B, TLR4, and TLR5. Intriguingly, TLR15, which is activated by fungal products, appeared to have been pseudogenized multiple times in the Eudyptes spp., but a full-length form was present as a rare haplotype at the population level. However, in vitro analysis revealed that even the full-length form of Eudyptes TLR15 was nonfunctional, indicating an ancestral cryptic pseudogenization prior to its eventual disruption multiple times in the Eudyptes lineage. This unusual pseudogenization event could provide an insight into immune adaptation to fungal pathogens such as Aspergillus, which is responsible for significant mortality in wild and captive bird populations.


Assuntos
Spheniscidae , Animais , Evolução Molecular , Seleção Genética , Spheniscidae/genética , Receptores Toll-Like/genética
10.
Nat Commun ; 12(1): 2918, 2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-34006882

RESUMO

Inquiline ants are highly specialized and obligate social parasites that infiltrate and exploit colonies of closely related species. They have evolved many times convergently, are often evolutionarily young lineages, and are almost invariably rare. Focusing on the leaf-cutting ant genus Acromyrmex, we compared genomes of three inquiline social parasites with their free-living, closely-related hosts. The social parasite genomes show distinct signatures of erosion compared to the host lineages, as a consequence of relaxed selective constraints on traits associated with cooperative ant colony life and of inquilines having very small effective population sizes. We find parallel gene losses, particularly in olfactory receptors, consistent with inquiline species having highly reduced social behavioral repertoires. Many of the genomic changes that we uncover resemble those observed in the genomes of obligate non-social parasites and intracellular endosymbionts that branched off into highly specialized, host-dependent niches.


Assuntos
Formigas/genética , Genoma de Inseto/genética , Parasitos/genética , Comportamento Social , Animais , Formigas/classificação , Formigas/fisiologia , Evolução Molecular , Feminino , Rearranjo Gênico/genética , Genômica/métodos , Interações Hospedeiro-Parasita , Proteínas de Insetos/classificação , Proteínas de Insetos/genética , Masculino , Parasitos/classificação , Parasitos/fisiologia , Filogenia , Receptores Odorantes/classificação , Receptores Odorantes/genética , Especificidade da Espécie
11.
Cell ; 184(5): 1377-1391.e14, 2021 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-33545088

RESUMO

Rich fossil evidence suggests that many traits and functions related to terrestrial evolution were present long before the ancestor of lobe- and ray-finned fishes. Here, we present genome sequences of the bichir, paddlefish, bowfin, and alligator gar, covering all major early divergent lineages of ray-finned fishes. Our analyses show that these species exhibit many mosaic genomic features of lobe- and ray-finned fishes. In particular, many regulatory elements for limb development are present in these fishes, supporting the hypothesis that the relevant ancestral regulation networks emerged before the origin of tetrapods. Transcriptome analyses confirm the homology between the lung and swim bladder and reveal the presence of functional lung-related genes in early ray-finned fishes. Furthermore, we functionally validate the essential role of a jawed vertebrate highly conserved element for cardiovascular development. Our results imply the ancestors of jawed vertebrates already had the potential gene networks for cardio-respiratory systems supporting air breathing.


Assuntos
Evolução Biológica , Peixes/genética , Nadadeiras de Animais/fisiologia , Animais , Fenômenos Fisiológicos Cardiovasculares , Sistema Cardiovascular/anatomia & histologia , Extremidades/fisiologia , Peixes/classificação , Genoma , Pulmão/anatomia & histologia , Pulmão/fisiologia , Filogenia , Receptores Odorantes/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcriptoma , Vertebrados/classificação , Vertebrados/genética
12.
Angiology ; 72(4): 371-380, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33307720

RESUMO

Genome-wide association studies have shown that a disintegrin and metalloproteinase with thrombospondin motifs 9 (ADAMTS-9) is associated with the development of atherosclerosis. We assessed the level of ADAMTS-9 in patients with coronary artery disease (CAD) and its severity and prognosis. We selected 666 participants who underwent coronary angiography in our hospital and met the inclusion and exclusion criteria; participants included non-CAD patients, patients with stable angina pectoris (SAP), unstable angina, non-ST-segment elevation myocardial infarction, or ST-segment elevation myocardial infarction. The serum level of ADAMTS-9 was higher in patients with CAD than in non-CAD patients (37.53 ± 8.55 ng/mL vs 12.04 ± 7.02 ng/mL, P < .001) and was an independent predictor for CAD (odds ratio = 1.871, 95% CI: 1.533-2.283, P < .001). Subgroup analysis showed that compared with the SAP group, the acute coronary syndrome groups had higher serum levels of ADAMTS-9. In addition, the level of ADAMTS-9 was related to the SYNTAX score (r = 0.523, P < .001). Patients with acute myocardial infarction (AMI) with elevated levels of ADAMTS-9 had a higher risk of major adverse cardiovascular events (MACE) within 12 months than those with lower levels (log-rank = 4.490, P = .034). Plasma ADAMTS-9 levels may be useful for the diagnosis of CAD and as predictors of MACE in AMI patients.


Assuntos
Proteína ADAMTS9/sangue , Síndrome Coronariana Aguda/sangue , Angina Estável/sangue , Angina Instável/sangue , Doença da Artéria Coronariana/sangue , Infarto do Miocárdio sem Supradesnível do Segmento ST/sangue , Infarto do Miocárdio com Supradesnível do Segmento ST/sangue , Síndrome Coronariana Aguda/diagnóstico por imagem , Adulto , Idoso , Angina Estável/diagnóstico por imagem , Angina Instável/diagnóstico por imagem , Biomarcadores/sangue , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio sem Supradesnível do Segmento ST/diagnóstico por imagem , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Índice de Gravidade de Doença , Regulação para Cima
13.
Proc Natl Acad Sci U S A ; 117(29): 17135-17141, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32631983

RESUMO

For social animals, the genotypes of group members affect the social environment, and thus individual behavior, often indirectly. We used genome-wide association studies (GWAS) to determine the influence of individual vs. group genotypes on aggression in honey bees. Aggression in honey bees arises from the coordinated actions of colony members, primarily nonreproductive "soldier" bees, and thus, experiences evolutionary selection at the colony level. Here, we show that individual behavior is influenced by colony environment, which in turn, is shaped by allele frequency within colonies. Using a population with a range of aggression, we sequenced individual whole genomes and looked for genotype-behavior associations within colonies in a common environment. There were no significant correlations between individual aggression and specific alleles. By contrast, we found strong correlations between colony aggression and the frequencies of specific alleles within colonies, despite a small number of colonies. Associations at the colony level were highly significant and were very similar among both soldiers and foragers, but they covaried with one another. One strongly significant association peak, containing an ortholog of the Drosophila sensory gene dpr4 on linkage group (chromosome) 7, showed strong signals of both selection and admixture during the evolution of gentleness in a honey bee population. We thus found links between colony genetics and group behavior and also, molecular evidence for group-level selection, acting at the colony level. We conclude that group genetics dominates individual genetics in determining the fatal decision of honey bees to sting.


Assuntos
Agressão , Abelhas/genética , Frequência do Gene/genética , Genoma de Inseto/genética , Animais , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único/genética , Comportamento Social
14.
Proc Natl Acad Sci U S A ; 117(24): 13615-13625, 2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32471944

RESUMO

Developmental plasticity generates phenotypic variation, but how it contributes to evolutionary change is unclear. Phenotypes of individuals in caste-based (eusocial) societies are particularly sensitive to developmental processes, and the evolutionary origins of eusociality may be rooted in developmental plasticity of ancestral forms. We used an integrative genomics approach to evaluate the relationships among developmental plasticity, molecular evolution, and social behavior in a bee species (Megalopta genalis) that expresses flexible sociality, and thus provides a window into the factors that may have been important at the evolutionary origins of eusociality. We find that differences in social behavior are derived from genes that also regulate sex differentiation and metamorphosis. Positive selection on social traits is influenced by the function of these genes in development. We further identify evidence that social polyphenisms may become encoded in the genome via genetic changes in regulatory regions, specifically in transcription factor binding sites. Taken together, our results provide evidence that developmental plasticity provides the substrate for evolutionary novelty and shapes the selective landscape for molecular evolution in a major evolutionary innovation: Eusociality.


Assuntos
Abelhas/crescimento & desenvolvimento , Abelhas/fisiologia , Animais , Abelhas/genética , Comportamento Animal , Evolução Biológica , Evolução Molecular , Feminino , Genoma de Inseto , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Masculino , Metamorfose Biológica , Comportamento Social
16.
Diabetes Metab Syndr Obes ; 12: 1697-1703, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31564937

RESUMO

BACKGROUND: Liraglutide reduces blood glucose, body weight and blood lipid levels. Hormone-sensitive lipase (HSL) is a key enzyme in lipolysis. Evidence from our and other studies have demonstrated that adenylate cyclase 3 (AC3) is associated with obesity and can be upregulated by liraglutide in obese mice. In the present study, we investigated whether hepatic HSL activity is regulated by liraglutide and characterized the effect of liraglutide in the AC3/protein kinase A (PKA)/HSL signalling pathway. METHODS: Obese mice or their lean littermates were treated with liraglutide or saline for 8 weeks. Serum was collected for the measurement of insulin and lipids. We investigated hepatic AC3, HSL and phosphorylated HSL Ser-660 (p-HSL(S660)) protein expression levels andAC3 and HSL mRNA expression levels and cyclic adenosine monophosphate (cAMP), PKA activity in liver tissue. RESULTS: Liraglutide treatment decreased triglycerides (TGs) and free fatty acids (FFAs), increased glycerol, and upregulated hepatic AC3 and p-HSL(s660) levels and cAMP and PKA activities. CONCLUSION: The results suggest that liraglutide can upregulates AC3/PKA/HSL pathway and may promotes lipolysis.

17.
Gigascience ; 8(9)2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31531675

RESUMO

BACKGROUND: Penguins (Sphenisciformes) are a remarkable order of flightless wing-propelled diving seabirds distributed widely across the southern hemisphere. They share a volant common ancestor with Procellariiformes close to the Cretaceous-Paleogene boundary (66 million years ago) and subsequently lost the ability to fly but enhanced their diving capabilities. With ∼20 species among 6 genera, penguins range from the tropical Galápagos Islands to the oceanic temperate forests of New Zealand, the rocky coastlines of the sub-Antarctic islands, and the sea ice around Antarctica. To inhabit such diverse and extreme environments, penguins evolved many physiological and morphological adaptations. However, they are also highly sensitive to climate change. Therefore, penguins provide an exciting target system for understanding the evolutionary processes of speciation, adaptation, and demography. Genomic data are an emerging resource for addressing questions about such processes. RESULTS: Here we present a novel dataset of 19 high-coverage genomes that, together with 2 previously published genomes, encompass all extant penguin species. We also present a well-supported phylogeny to clarify the relationships among penguins. In contrast to recent studies, our results demonstrate that the genus Aptenodytes is basal and sister to all other extant penguin genera, providing intriguing new insights into the adaptation of penguins to Antarctica. As such, our dataset provides a novel resource for understanding the evolutionary history of penguins as a clade, as well as the fine-scale relationships of individual penguin lineages. Against this background, we introduce a major consortium of international scientists dedicated to studying these genomes. Moreover, we highlight emerging issues regarding ensuring legal and respectful indigenous consultation, particularly for genomic data originating from New Zealand Taonga species. CONCLUSIONS: We believe that our dataset and project will be important for understanding evolution, increasing cultural heritage and guiding the conservation of this iconic southern hemisphere species assemblage.


Assuntos
Genoma , Spheniscidae/genética , Animais , Evolução Molecular , Filogenia
18.
Sci China Life Sci ; 62(4): 566-578, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30929190

RESUMO

Pattern recognition receptors (PRRs) play important roles in innate immunity system and trigger the specific pathogen recognition by detecting the pathogen-associated molecular patterns. The main four PRRs components including Toll-like receptors (TLRs), RIG-I-like receptors (RLRs), NOD-like receptors (NLRs) and C-type lectin receptors (CLRs) were surveyed in the five genomes of non-teleost ray-finned fishes (NTR) including bichir (Polypterus senegalus), American paddlefish (Polyodon spathula), alligator gar (Atractosteus spatula), spotted gar (Lepisosteus oculatus) and bowfin (Amia calva), representing all the four major basal groups of ray-finned fishes. The result indicates that all the four PRRs components have been well established in these NTR fishes. In the RLR-MAVS signal pathway, which detects intracellular RNA ligands to induce production of type I interferons (IFNs), the MAVS was lost in bichir particularly. Also, the essential genes of recognition of Lipopolysaccharide (LPS) commonly in mammals like MD2, LY96 and LBP could not be identified in NTR fishes. It is speculated that TLR4 in NTR fishes may act as a cooperator with other PRRs and has a different pathway of recognizing LPS compared with that in mammals. In addition, we provide a survey of NLR and CLR in NTR fishes. The CLRs results suggest that Group V receptors are absent in fishes and Group II and VI receptors are well established in the early vertebrate evolution. Our comprehensive research of PRRs involving NTR fishes provides a new insight into PRR evolution in primitive vertebrate.


Assuntos
Peixes/genética , Receptores de Reconhecimento de Padrão/genética , Animais , Proteína DEAD-box 58/genética , Evolução Molecular , Peixes/classificação , Imunidade Inata/genética , Lectinas Tipo C/genética , Proteínas NLR/genética , Filogenia , Transdução de Sinais/imunologia , Receptores Toll-Like/genética
19.
Mol Biol Evol ; 36(4): 784-797, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30722030

RESUMO

The emergence of islands has been linked to spectacular radiations of diverse organisms. Although penguins spend much of their lives at sea, they rely on land for nesting, and a high proportion of extant species are endemic to geologically young islands. Islands may thus have been crucial to the evolutionary diversification of penguins. We test this hypothesis using a fossil-calibrated phylogeny of mitochondrial genomes (mitogenomes) from all extant and recently extinct penguin taxa. Our temporal analysis demonstrates that numerous recent island-endemic penguin taxa diverged following the formation of their islands during the Plio-Pleistocene, including the Galápagos (Galápagos Islands), northern rockhopper (Gough Island), erect-crested (Antipodes Islands), Snares crested (Snares) and royal (Macquarie Island) penguins. Our analysis also reveals two new recently extinct island-endemic penguin taxa from New Zealand's Chatham Islands: Eudyptes warhami sp. nov. and a dwarf subspecies of the yellow-eyed penguin, Megadyptes antipodes richdalei ssp. nov. Eudyptes warhami diverged from the Antipodes Islands erect-crested penguin between 1.1 and 2.5 Ma, shortly after the emergence of the Chatham Islands (∼3 Ma). This new finding of recently evolved taxa on this young archipelago provides further evidence that the radiation of penguins over the last 5 Ma has been linked to island emergence. Mitogenomic analyses of all penguin species, and the discovery of two new extinct penguin taxa, highlight the importance of island formation in the diversification of penguins, as well as the extent to which anthropogenic extinctions have affected island-endemic taxa across the Southern Hemisphere's isolated archipelagos.


Assuntos
Especiação Genética , Genoma Mitocondrial , Ilhas , Spheniscidae/genética , Animais , Fósseis , Nova Zelândia , Filogeografia
20.
G3 (Bethesda) ; 9(3): 625-634, 2019 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-30642875

RESUMO

Alkali bees (Nomia melanderi) are solitary relatives of the halictine bees, which have become an important model for the evolution of social behavior, but for which few solitary comparisons exist. These ground-nesting bees defend their developing offspring against pathogens and predators, and thus exhibit some of the key traits that preceded insect sociality. Alkali bees are also efficient native pollinators of alfalfa seed, which is a crop of major economic value in the United States. We sequenced, assembled, and annotated a high-quality draft genome of 299.6 Mbp for this species. Repetitive content makes up more than one-third of this genome, and previously uncharacterized transposable elements are the most abundant type of repetitive DNA. We predicted 10,847 protein coding genes, and identify 479 of these undergoing positive directional selection with the use of population genetic analysis based on low-coverage whole genome sequencing of 19 individuals. We found evidence of recent population bottlenecks, but no significant evidence of population structure. We also identify 45 genes enriched for protein translation and folding, transcriptional regulation, and triglyceride metabolism evolving slower in alkali bees compared to other halictid bees. These resources will be useful for future studies of bee comparative genomics and pollinator health research.


Assuntos
Abelhas/genética , Genoma de Inseto , Anotação de Sequência Molecular , Sequenciamento Completo do Genoma , Animais , Feminino , Genética Populacional , Masculino , Filogenia
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