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1.
Am J Primatol ; : e23662, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39041384

RESUMO

Despite decades of field study, very little is known about the molecular ecology of gibbons, particularly as it relates to their ability to disperse across degraded and fragmentary landscapes. The critically endangered western black crested gibbon (Nomascus concolor) has been reduced to a small, fragmented population with about 1300 individuals. In the largest population genetic study of free-ranging gibbons to date, we sampled 47 of these gibbons from 13 sites in China and generated 15 polymorphic autosomal microsatellite markers. We identify three population clusters of N. concolor in Yunnan centered in 1) the Wuliang and Ailao Mountains, 2) the Yongde Daxueshan Mountains, and 3) an isolated remnant near the border with Vietnam. Within the Wuliang Mountains, we identified four subclusters, three of which are bounded by high-altitude rhododendron forest, and one that is isolated from the main population by ~2 km of degraded forest and pasture. Least-cost path analysis and isolation by resistance modeling demonstrates that the population genetic distances among gibbons in Wuliangshan National Nature Reserve are significantly correlated with geographic paths that avoid use of high-altitude rhododendron forest in favor of evergreen broadleaf forest. Although these gibbons have likely undergone reductions in heterozygosity from recent consanguineous mating, we suggest that their active avoidance of inbreeding on the population level maintains higher than expected levels of genetic diversity. This research provides new insights into how gibbons interact with heterogeneous environments and expands our understanding of their molecular ecology and conservation genetics.

2.
Integr Zool ; 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39075927

RESUMO

Our findings reveal that the western black crested gibbon (Nomascus concolor) did not divide into different subspecies, and the relatively low level of genetic diversity emphasizes the importance of monitoring this indicator for vulnerable wildlife. Meanwhile, phylogeographic analysis of the Nomascus genus shows a north-to-south trend of ancestral geographic distribution.

3.
Emerg Microbes Infect ; 13(1): 2373307, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38953857

RESUMO

SARS-CoV-2 has been evolving into a large number of variants, including the highly pathogenic Delta variant, and the currently prevalent Omicron subvariants with extensive evasion capability, which raises an urgent need to develop new broad-spectrum neutralizing antibodies. Herein, we engineer two IgG-(scFv)2 form bispecific antibodies with overlapping epitopes (bsAb1) or non-overlapping epitopes (bsAb2). Both bsAbs are significantly superior to the parental monoclonal antibodies in terms of their antigen-binding and virus-neutralizing activities against all tested circulating SARS-CoV-2 variants including currently dominant JN.1. The bsAb1 can efficiently neutralize all variants insensitive to parental monoclonal antibodies or the cocktail with IC50 lower than 20 ng/mL, even slightly better than bsAb2. Furthermore, the cryo-EM structures of bsAb1 in complex with the Omicron spike protein revealed that bsAb1 with overlapping epitopes effectively locked the S protein, which accounts for its conserved neutralization against Omicron variants. The bispecific antibody strategy engineered from overlapping epitopes provides a novel solution for dealing with viral immune evasion.


Assuntos
Anticorpos Biespecíficos , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19 , Epitopos , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Anticorpos Biespecíficos/imunologia , Anticorpos Biespecíficos/química , Anticorpos Biespecíficos/farmacologia , SARS-CoV-2/imunologia , Anticorpos Neutralizantes/imunologia , Humanos , Anticorpos Antivirais/imunologia , Epitopos/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/química , COVID-19/imunologia , COVID-19/virologia , COVID-19/prevenção & controle , Testes de Neutralização
4.
Conserv Biol ; : e14311, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38853694

RESUMO

Conducting conservation research and establishing protected areas (PAs) based on research results are critical to biodiversity conservation. However, the effect of research and PAs on conservation of threatened species has rarely been evaluated simultaneously. We collected data on PAs from 2000 for 2021 and determined the number of publications on global primates (published from 1950 to 2021) to assess the effect of PAs, research, and biological and socioeconomic factors on the current International Union for Conservation of Nature endangered status and change in status. We used the MCMCglmm package to conduct a phylogenetic comparative analysis to control the phylogenetic relationship of primate species. The status of 24.6% (82 of 333) of species assessed at least twice declined. Only the black lion tamarin (Leontopithecus chrysopygus) had an improved status. Species with status declines mostly occurred on the south coast of West Africa and in Madagascar. PAs covered 22.1% of each species' range. Forest loss in PAs (5.5%) was significantly lower than forest loss within 5 km outside PAs (13.8%), suggesting PAs effectively mitigated forest loss. Both the median number of total publications and conservation publications on critically endangered species were higher than those of other categories. Models showed that PA coverage and number of publications or conservation-focused publications were not related to current status or change in status over time. A decline in status was not related to creation of PAs or increase of research since the last assessment. Our results suggest that current PAs and research are not reversing the extinction crisis of global primates. Doing more conservation-oriented research, strengthening management of current PAs, and expanding PAs will be needed to protect primates globally.


Efectos de la cobertura e investigación de áreas protegidas sobre el estado de conservación de los primates a nivel mundial Resumen La investigación para la conservación y la creación de áreas protegidas (AP) con base en sus resultados son de suma importancia para conservar la biodiversidad. Sin embargo, pocas veces se ha analizado de forma simultánea el efecto de la investigación y las AP sobre la conservación de especies amenazadas. Recolectamos datos sobre las AP entre el 2000 y el 2021 y determinamos el número de artículos sobre primates publicados entre 1950 y 2021 para evaluar el efecto de las AP, la investigación y los factores biológicos y socioeconómicos sobre el estado actual de en peligro y de cambio de estatus de la Unión Internacional para la Conservación de la Naturaleza. Usamos el paquete MCMCglmm para realizar un estudio filogenético comparativo para analizar la relación filogenética del estado de las especies y del cambio de estatus de primates. El estatus del 24.6% (82 de 333) de las especies analizadas declinó al menos dos veces. Solamente el tití leoncito (Leontopithecus chrysopygus) tuvo una mejoraría en su estado. Las especies con declinación en su estado se ubicaron principalmente en la costa sur del Oeste de África y en Madagascar. Las AP cubrieron el 22.1% de la distribución de cada especie. La pérdida de bosques en las AP (5.5%) fue mucho menor que la pérdida dentro de los primeros 5 km fuera de las AP (13.8%), lo que sugiere que las AP mitigan eficientemente la pérdida de bosque. Tanto el número medio de publicaciones totales como el de publicaciones sobre la conservación de especies en peligro crítico fue mayor que aquellos de cualquier otra categoría. Los modelos mostraron que la cobertura de AP y el número de publicaciones o de publicaciones enfocadas en la conservación no estaban relacionados con el estado actual o el cambio de estado. La declinación del estado no estuvo relacionada con la creación de AP o el incremento en la investigación desde nuestro último análisis. Nuestros resultados sugieren que la investigación y las AP actuales no están revirtiendo la crisis mundial de extinción de primates. Para proteger a los primates se necesitará realizar más investigación orientada a la conservación, fortalecer el manejo actual de las AP, así como expandirlas.

5.
Exp Dermatol ; 33(6): e15111, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38840411

RESUMO

Keloids are pathological scar tissue resulting from skin trauma or spontaneous formation, often accompanied by itching and pain. Although GNAS antisense RNA 1 (GNAS-AS1) shows abnormal upregulation in keloids, the underlying molecular mechanism is unclear. The levels of genes and proteins in clinical tissues from patients with keloids and human keloid fibroblasts (HKFs) were measured using quantitative reverse transcription PCR, western blot and enzyme-linked immunosorbent assay. The features of HKFs, including proliferation and migration, were evaluated using cell counting kit 8 and a wound healing assay. The colocalization of GNAS-AS1 and miR-196a-5p in HKFs was measured using fluorescence in situ hybridization. The relationships among GNAS-AS1, miR-196a-5p and C-X-C motif chemokine ligand 12 (CXCL12) in samples from patients with keloids were analysed by Pearson correlation analysis. Gene interactions were validated by chromatin immunoprecipitation and luciferase reporter assays. GNAS-AS1 and CXCL12 expression were upregulated and miR-196a-5p expression was downregulated in clinical tissues from patients with keloids. GNAS-AS1 knockdown inhibited proliferation, migration, and extracellular matrix (ECM) accumulation of HKFs, all of which were reversed by miR-196a-5p downregulation. Signal transducer and activator of transcription 3 (STAT3) induced GNAS-AS1 transcription through GNAS-AS1 promoter interaction, and niclosamide, a STAT3 inhibitor, decreased GNAS-AS1 expression. GNAS-AS1 positively regulated CXCL12 by sponging miR-196-5p. Furthermore, CXCL12 knockdown restrained STAT3 phosphorylation in HKFs. Our findings revealed a feedback loop of STAT3/GNAS-AS1/miR-196a-5p/CXCL12/STAT3 that promoted HKF proliferation, migration and ECM accumulation and affected keloid progression.


Assuntos
Proliferação de Células , Quimiocina CXCL12 , Fibroblastos , Queloide , MicroRNAs , RNA Longo não Codificante , Fator de Transcrição STAT3 , Queloide/metabolismo , Queloide/genética , Queloide/patologia , Humanos , MicroRNAs/metabolismo , MicroRNAs/genética , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT3/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Quimiocina CXCL12/metabolismo , Quimiocina CXCL12/genética , Fibroblastos/metabolismo , Movimento Celular , Retroalimentação Fisiológica , Cromograninas/genética , Cromograninas/metabolismo , Masculino , Feminino , Subunidades alfa Gs de Proteínas de Ligação ao GTP/genética , Subunidades alfa Gs de Proteínas de Ligação ao GTP/metabolismo , Transdução de Sinais , Adulto , Células Cultivadas , Regulação para Cima
6.
Am J Primatol ; 86(8): e23636, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38824636

RESUMO

As a central topic in Behavioral Ecology, animal space use involves dynamic responses to social and ecological factors. We collared 22 rhesus macaques (Macaca mulatta) from six groups on Neilingding Island, China, and collected 80,625 hourly fixes over a year. Using this high-resolution location data set, we quantified the macaques' space use at the individual level and tested the ecological constraints model while considering various environmental and human interfering factors. As predicted by the ecological constraints model, macaques in larger groups had longer daily path lengths (DPLs) and larger home ranges. We found an inverted U-shape relationship between mean daily temperatures and DPLs, indicating that macaques traveled farther on mild temperature days, while they decreased DPLs when temperatures were too high or too low. Anthropogenic food subsidies were positively correlated to DPLs, while the effect of rainfall was negative. Macaques decreased their DPLs and core areas when more flowers and less leaves were available, suggesting that macaques shifted their space use patterns to adapt to the seasonal differences in food resources. By applying GPS collars on a large number of individuals living on a small island, we gained valuable insights into within-group exploitation competition in wild rhesus macaques.


Assuntos
Sistemas de Informação Geográfica , Comportamento de Retorno ao Território Vital , Macaca mulatta , Animais , Macaca mulatta/fisiologia , China , Masculino , Feminino , Ecossistema , Temperatura , Estações do Ano , Ilhas
7.
Nat Commun ; 15(1): 4330, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773072

RESUMO

The Hendra and Nipah viruses (HNVs) are highly pathogenic pathogens without approved interventions for human use. In addition, the interaction pattern between the attachment (G) and fusion (F) glycoproteins required for virus entry remains unclear. Here, we isolate a panel of Macaca-derived G-specific antibodies that cross-neutralize HNVs via multiple mechanisms. The most potent antibody, 1E5, confers adequate protection against the Nipah virus challenge in female hamsters. Crystallography demonstrates that 1E5 has a highly similar binding pattern to the receptor. In cryo-electron microscopy studies, the tendency of 1E5 to bind to the upper or lower heads results in two distinct quaternary structures of G. Furthermore, we identify the extended outer loop ß1S2-ß1S3 of G and two pockets on the apical region of fusion (F) glycoprotein as the essential sites for G-F interactions. This work highlights promising drug candidates against HNVs and contributes deeper insights into the viruses.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Microscopia Crioeletrônica , Infecções por Henipavirus , Proteínas Virais de Fusão , Animais , Anticorpos Neutralizantes/imunologia , Feminino , Anticorpos Antivirais/imunologia , Infecções por Henipavirus/virologia , Infecções por Henipavirus/imunologia , Proteínas Virais de Fusão/imunologia , Proteínas Virais de Fusão/química , Humanos , Proteínas do Envelope Viral/imunologia , Proteínas do Envelope Viral/química , Vírus Nipah/imunologia , Internalização do Vírus/efeitos dos fármacos , Henipavirus/imunologia , Cricetinae , Reações Cruzadas/imunologia , Vírus Hendra/imunologia , Macaca , Mesocricetus , Cristalografia por Raios X
8.
Nat Commun ; 15(1): 2987, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582870

RESUMO

Nipah virus (NiV) is a World Health Organization priority pathogen and there are currently no approved drugs for clinical immunotherapy. Through the use of a naïve human phage-displayed Fab library, two neutralizing antibodies (NiV41 and NiV42) targeting the NiV receptor binding protein (RBP) were identified. Following affinity maturation, antibodies derived from NiV41 display cross-reactivity against both NiV and Hendra virus (HeV), whereas the antibody based on NiV42 is only specific to NiV. Results of immunogenetic analysis reveal a correlation between the maturation of antibodies and their antiviral activity. In vivo testing of NiV41 and its mature form (41-6) show protective efficacy against a lethal NiV challenge in hamsters. Furthermore, a 2.88 Å Cryo-EM structure of the tetrameric RBP and antibody complex demonstrates that 41-6 blocks the receptor binding interface. These findings can be beneficial for the development of antiviral drugs and the design of vaccines with broad spectrum against henipaviruses.


Assuntos
Infecções por Henipavirus , Vírus Nipah , Humanos , Anticorpos Neutralizantes/metabolismo , Vírus Nipah/metabolismo , Anticorpos Antivirais
9.
ACS Omega ; 9(9): 10782-10792, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38463299

RESUMO

Jinguanchong deposit, a part of the Mingyuefeng ore field in eastern Hunan Province, China, is a typical perigranitic uranium deposit (a subtype of granite-related deposit) discovered recently with considerable uranium mineralization. Herein, uraninite, the primary ore mineral in the deposit, was investigated via scanning electron microscopy and electron probe microanalysis. Additionally, laser ablation-inductively coupled plasma-mass spectrometry was used for the first time to determine the in situ U-Pb age and the rare-earth element characteristics of uraninite. Uraninite mainly comprises UO2, CaO, and PbO with a low ThO2 content. Uraninite exhibits a low total content of rare-earth elements with a distinct fractionation between light and heavy rare-earth elements while displaying a negative Eu anomaly. The presence of major elements and rare-earth elements in uraninite suggests its formation within a hydrothermal environment at moderate to low temperatures below 350 °C, thereby classifying the Jinguanchong deposit as a typical hydrothermal vein-type uranium deposit. The uranium metallogenic age is determined to be 93.8 ± 1.4 Ma, falling within the midlate Cretaceous period. This age corresponds to the Mesozoic lithospheric extension and thinning events (approximately 85-95 Ma) in South China, suggesting that the formation of the Jinguanchong uranium deposit might be associated with the tectonic dynamics of lithospheric extension and thinning.

10.
Nat Commun ; 15(1): 1254, 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38341424

RESUMO

It has been extensively studied that the gut microbiome provides animals flexibility to adapt to food variability. Yet, how gut phageome responds to diet variation of wild animals remains unexplored. Here, we analyze the eco-evolutionary dynamics of gut phageome in six wild gibbons (Hoolock tianxing) by collecting individually-resolved fresh fecal samples and parallel feeding behavior data for 15 consecutive months. Application of complementary viral and microbial metagenomics recovers 39,198 virulent and temperate phage genomes from the feces. Hierarchical cluster analyses show remarkable seasonal diet variations in gibbons. From high-fruit to high-leaf feeding period, the abundances of phage populations are seasonally fluctuated, especially driven by the increased abundance of virulent phages that kill the Lachnospiraceae hosts, and a decreased abundance of temperate phages that piggyback the Bacteroidaceae hosts. Functional profiling reveals an enrichment through horizontal gene transfers of toxin-antitoxin genes on temperate phage genomes in high-leaf season, potentially conferring benefits to their prokaryotic hosts. The phage-host ecological dynamics are driven by the coevolutionary processes which select for tail fiber and DNA primase genes on virulent and temperate phage genomes, respectively. Our results highlight complex phageome-microbiome interactions as a key feature of the gibbon gut microbial ecosystem responding to the seasonal diet.


Assuntos
Bacteriófagos , Hylobates , Hylobatidae , Animais , Estações do Ano , Ecossistema , Viroma , Dieta , Bacteriófagos/genética , Frutas
11.
Mikrochim Acta ; 191(3): 147, 2024 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-38374514

RESUMO

An innovative synthesis of boron and nitrogen co-doped ceria-based nanoparticles (B/N-CeFNPs) with bright blue fluorescence emission is reported using the hydrothermal method. Based on the aggregation-induced emission enhancement (AIEE) effect between B/N-CeFNPs and chlortetracycline (CTC), a rapid detection method for CTC through fluorescence enhancement was developed. In addition, through the electron transfer process (ET), fluorescence resonance energy transfer (FRET) effect and static quenching between B/N-CeFNPs and oxytetracycline (OTC), a ratio fluorescence strategy for detecting OTC was generated. The fluorescence of B/N-CeFNPs at 410 nm can be effectively quenched by OTC, and new fluorescence emission appears at a wavelength of 500 nm. B/N-CeFNPs showed good linear responses with CTC and OTC in the range 0.1-1 µM and 1-40 µM, respectively. This system was used to simultaneously detect the CTC and OTC in milk and honey, realizing multi-residues detection of TCs in actual samples by using the same ceria-based fluorescence nanomaterial.


Assuntos
Clortetraciclina , Nanopartículas , Oxitetraciclina , Animais , Boro , Espectrometria de Fluorescência/métodos , Antibacterianos
12.
Plant Physiol ; 195(1): 552-565, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38243383

RESUMO

Plant trichome development is influenced by diverse developmental and environmental signals, but the molecular mechanisms involved are not well understood in most plant species. Fruit spines (trichomes) are an important trait in cucumber (Cucumis sativus L.), as they affect both fruit smoothness and commercial quality. Spine Base Size1 (CsSBS1) has been identified as essential for regulating fruit spine size in cucumber. Here, we discovered that CsSBS1 controls a season-dependent phenotype of spine base size in wild-type plants. Decreased light intensity led to reduced expression of CsSBS1 and smaller spine base size in wild-type plants, but not in the mutants with CsSBS1 deletion. Additionally, knockout of CsSBS1 resulted in smaller fruit spine base size and eliminated the light-induced expansion of spines. Overexpression of CsSBS1 increased spine base size and rescued the decrease in spine base size under low light conditions. Further analysis revealed that ELONGATED HYPOTCOTYL5 (HY5), a major transcription factor involved in light signaling pathways, directly binds to the promoter of CsSBS1 and activates its expression. Knockout of CsHY5 led to smaller fruit spine base size and abolished the light-induced expansion of spines. Taken together, our study findings have clarified a CsHY5-CsSBS1 regulatory module that mediates light-regulated spine expansion in cucumber. This finding offers a strategy for cucumber breeders to develop fruit with stable appearance quality under changing light conditions.


Assuntos
Cucumis sativus , Regulação da Expressão Gênica de Plantas , Luz , Proteínas de Plantas , Cucumis sativus/genética , Cucumis sativus/crescimento & desenvolvimento , Cucumis sativus/efeitos da radiação , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Frutas/genética , Frutas/crescimento & desenvolvimento , Tricomas/genética , Tricomas/crescimento & desenvolvimento , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Fenótipo , Regiões Promotoras Genéticas/genética
13.
Curr Biol ; 34(5): 935-945.e3, 2024 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-38266649

RESUMO

Song coordination is a universal characteristic of human music. Many animals also produce well-coordinated duets or choruses that resemble human music. However, the mechanism and evolution of song coordination have only recently been studied in animals. Here, we studied the mechanism of song coordination in three closely related species of wild Nomascus gibbons that live in polygynous groups. In each species, song bouts were dominated by male solo sequences (referred to hereafter as male sequence), and females contributed stereotyped great calls to coordinate with males. Considering the function of rhythm in facilitating song coordination in human music and animal vocalizations, we predicted that adult males adjust their song rhythm to facilitate song coordination with females. In support of this prediction, we found that adult males produced significantly more isochronous rhythms with a faster tempo in male sequences that were followed by successful female great calls (a complete sequence with "introductory" and "wa" notes). The difference in isochrony and tempos between successful great call sequences and male sequences was smaller in N. concolor compared with the other two species, which may make it difficult for females to predict a male's precise temporal pattern. Consequently, adult females of N. concolor produced more failed great call (an incomplete sequence with only introductory notes) sequences. We propose that the high degree of rhythm change functions as an unambiguous signal that can be easily perceived by receivers. In this regard, gibbon vocalizations offer an instructive model to understand the origins and evolution of human music.


Assuntos
Hominidae , Humanos , Animais , Masculino , Feminino , Hylobates , Vocalização Animal , Comportamento Estereotipado
14.
Evol Appl ; 17(1): e13630, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38288030

RESUMO

Populations of Eurasian otters Lutra lutra, one of the most widely distributed apex predators in Eurasia, have been depleted mainly since the 1950s. However, a lack of information about their genomic diversity and how they are organized geographically in East Asia severely impedes our ability to monitor and conserve them in particular management units. Here, we re-sequenced and analyzed 20 otter genomes spanning continental East Asia, including a population at Kinmen, a small island off the Fujian coast, China. The otters form three genetic clusters (one of L. l. lutra in the north and two of L. l. chinensis in the south), which have diverged in the Holocene. These three clusters should be recognized as three conservation management units to monitor and manage independently. The heterozygosity of the East Asian otters is as low as that of the threatened carnivores sequenced. Historical effective population size trajectories inferred from genomic variations suggest that their low genomic diversity could be partially attributed to changes in the climate since the mid-Pleistocene and anthropogenic intervention since the Holocene. However, no evidence of genetic erosion, mutation load, or high level of inbreeding was detected in the presumably isolated Kinmen Island population. Any future in situ conservation efforts should consider this information for the conservation management units.

15.
Sci Rep ; 14(1): 416, 2024 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172177

RESUMO

The cao vit gibbon (Nomascus nasutus) is one of the rarest primates on Earth and now only survives in a single forest patch of less than 5000 ha on the Vietnam-China border. Accurate monitoring of the last remaining population is critical to inform ongoing conservation interventions and track conservation success over time. However, traditional methods for monitoring gibbons, involving triangulation of groups from their songs, are inherently subjective and likely subject to considerable measurement errors. To overcome this, we aimed to use 'vocal fingerprinting' to distinguish the different singing males in the population. During the 2021 population survey, we complemented the traditional observations made by survey teams with a concurrent passive acoustic monitoring array. Counts of gibbon group sizes were also assisted with a UAV-mounted thermal camera. After identifying eight family groups in the acoustic data and incorporating long-term data, we estimate that the population was comprised of 74 individuals in 11 family groups, which is 38% smaller than previously thought. We have no evidence that the population has declined-indeed it appears to be growing, with new groups having formed in recent years-and the difference is instead due to double-counting of groups in previous surveys employing the triangulation method. Indeed, using spatially explicit capture-recapture modelling, we uncovered substantial measurement error in the bearings and distances from field teams. We also applied semi- and fully-automatic approaches to clustering the male calls into groups, finding no evidence that we had missed any males with the manual approach. Given the very small size of the population, conservation actions are now even more urgent, in particular habitat restoration to allow the population to expand. Our new population estimate now serves as a more robust basis for informing management actions and tracking conservation success over time.


Assuntos
Hylobates , Hylobatidae , Animais , Masculino , Espécies em Perigo de Extinção , Ecossistema
17.
Talanta ; 270: 125550, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38104426

RESUMO

Developing ultrasensitive sensing platforms for trace ochratoxin A (OTA) in food safety is still challenging. Herein, we presented a novel dual-mode sensing strategy for fluorescence and colorimetric detection of OTA by combining the target-responsive hemin-encapsulated and copper nanoclusters (CuNCs) functionalized DNA hydrogel. Through simple assembly and in situ synthesis methods, fluorescence CuNCs are synthesized and modified on the 3D hydrophilic network structure of DNA cross-linked. OTA specifically recognized by Apt-linker can control the collapse of hydrogel, resulting in the fluorescence quenching of CuNCs and release of coated hemin. Interestingly, OTA could trigger Apt-linker conformational changes to form G-quadruplex structures, allowing the released hemin to form G-quadruplex/hemin DNAzyme via self-assembly. Fluorescence signal amplification could be achieved through further fluorescence quenching of CuNCs caused by DNAzyme-catalyzed hydrogen peroxide (H2O2) because of the peroxidase activity of DNAzyme. Simultaneously, DNAzyme could catalyze the H2O2-mediated oxidation of TMB to provide colorimetric signal. Thereafter, the DNA-CuNCs hydrogel exhibited low detection limits of 3.49 pg/mL in fluorescence mode and 0.25 ng/mL in colorimetric modality. Real sample analyses of foodstuffs showed satisfactory results, providing prospective potential for monitoring mycotoxin contaminant.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , DNA Catalítico , Quadruplex G , Ocratoxinas , DNA Catalítico/química , Cobre , Hidrogéis , Hemina/química , Peróxido de Hidrogênio/química , DNA , Técnicas Biossensoriais/métodos , Limite de Detecção , Aptâmeros de Nucleotídeos/química
18.
Nat Commun ; 14(1): 8001, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38049411

RESUMO

Despite the importance of Nitric Oxide (NO) as signaling molecule in both plant and animal development, the regulatory mechanisms downstream of NO remain largely unclear. Here, we show that NO is involved in Arabidopsis shoot stem cell control via modifying expression and activity of ARGONAUTE 4 (AGO4), a core component of the RNA-directed DNA Methylation (RdDM) pathway. Mutations in components of the RdDM pathway cause meristematic defects, and reduce responses of the stem cell system to NO signaling. Importantly, we find that the stem cell inducing WUSCHEL transcription factor directly interacts with AGO4 in a NO dependent manner, explaining how these two signaling systems may converge to modify DNA methylation patterns. Taken together, our results reveal that NO signaling plays an important role in controlling plant stem cell homeostasis via the regulation of de novo DNA methylation.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Metilação de DNA/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Óxido Nítrico/metabolismo , Meristema/genética , Meristema/metabolismo , Arabidopsis/metabolismo , RNA/metabolismo , Regulação da Expressão Gênica de Plantas
19.
Mol Biol Evol ; 40(11)2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37823401

RESUMO

The genus Macaca includes 23 species assigned into 4 to 7 groups. It exhibits the largest geographic range and represents the most successful example of adaptive radiation of nonhuman primates. However, intrageneric phylogenetic relationships among species remain controversial and have not been resolved so far. In this study, we conducted a phylogenomic analysis on 16 newly generated and 8 published macaque genomes. We found strong evidence supporting the division of this genus into 7 species groups. Incomplete lineage sorting (ILS) was the primary factor contributing to the discordance observed among gene trees; however, we also found evidence of hybridization events, specifically between the ancestral arctoides/sinica and silenus/nigra lineages that resulted in the hybrid formation of the fascicularis/mulatta group. Combined with fossil data, our phylogenomic data were used to establish a scenario for macaque radiation. These findings provide insights into ILS and potential ancient introgression events that were involved in the radiation of macaques, which will lead to a better understanding of the rapid speciation occurring in nonhuman primates.


Assuntos
Genoma , Macaca , Animais , Filogenia , Macaca/genética , Hibridização Genética
20.
Front Immunol ; 14: 1239179, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37868993

RESUMO

Introduction: The SARS-CoV-2 Omicron variant has become the dominant SARS-CoV-2 variant and exhibits immune escape to current COVID-19 vaccines, the further boosting strategies are required. Methods: We have conducted a non-randomized, open-label and parallel-controlled phase 4 trial to evaluate the magnitude and longevity of immune responses to booster vaccination with intramuscular adenovirus vectored vaccine (Ad5-nCoV), aerosolized Ad5-nCoV, a recombinant protein subunit vaccine (ZF2001) or homologous inactivated vaccine (CoronaVac) in those who received two doses of inactivated COVID-19 vaccines. Results: The aerosolized Ad5-nCoV induced the most robust and long-lasting neutralizing activity against Omicron variant and IFNg T-cell response among all the boosters, with a distinct mucosal immune response. SARS-CoV-2-specific mucosal IgA response was substantially generated in subjects boosted with the aerosolized Ad5-nCoV at day 14 post-vaccination. At month 6, participants boosted with the aerosolized Ad5-nCoV had remarkably higher median titer and seroconversion of the Omicron BA.4/5-specific neutralizing antibody than those who received other boosters. Discussion: Our findings suggest that aerosolized Ad5-nCoV may provide an efficient alternative in response to the spread of the Omicron BA.4/5 variant. Clinical trial registration: https://www.chictr.org.cn/showproj.html?proj=152729, identifier ChiCTR2200057278.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , SARS-CoV-2 , COVID-19/prevenção & controle , Imunidade nas Mucosas , Anticorpos
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