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1.
Cell ; 157(7): 1552-64, 2014 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-24949968

RESUMO

The hippocampus, as part of the cerebral cortex, is essential for memory formation and spatial navigation. Although it has been extensively studied, especially as a model system for neurophysiology, the cellular processes involved in constructing and organizing the hippocampus remain largely unclear. Here, we show that clonally related excitatory neurons in the developing hippocampus are progressively organized into discrete horizontal, but not vertical, clusters in the stratum pyramidale, as revealed by both cell-type-specific retroviral labeling and mosaic analysis with double markers (MADM). Moreover, distinct from those in the neocortex, sister excitatory neurons in the cornu ammonis 1 region of the hippocampus rarely develop electrical or chemical synapses with each other. Instead, they preferentially receive common synaptic input from nearby fast-spiking (FS), but not non-FS, interneurons and exhibit synchronous synaptic activity. These results suggest that shared inhibitory input may specify horizontally clustered sister excitatory neurons as functional units in the hippocampus.


Assuntos
Hipocampo/citologia , Hipocampo/fisiologia , Animais , Embrião de Mamíferos/citologia , Técnicas Genéticas , Interneurônios , Camundongos , Neurônios/fisiologia , Coloração e Rotulagem/métodos , Sinapses
2.
Genes Dev ; 32(11-12): 763-780, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29899142

RESUMO

Proper organization and orderly mitosis of radial glial progenitors (RGPs) drive the formation of a laminated mammalian cortex in the correct size. However, the molecular underpinnings of the intricate process remain largely unclear. Here we show that RGP behavior and cortical development are controlled by temporally distinct actions of partitioning-defective 3 (PARD3) in concert with dynamic HIPPO signaling. RGPs lacking PARD3 exhibit developmental stage-dependent abnormal switches in division mode, resulting in an initial overproduction of RGPs located largely outside the ventricular zone at the expense of deep-layer neurons. Ectopically localized RGPs subsequently undergo accelerated and excessive neurogenesis, leading to the formation of an enlarged cortex with massive heterotopia and increased seizure susceptibility. Simultaneous removal of HIPPO pathway effectors Yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ) suppresses cortical enlargement and heterotopia formation. These results define a dynamic regulatory program of mammalian cortical development and highlight a progenitor origin of megalencephaly with ribbon heterotopia and epilepsy.


Assuntos
Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Córtex Cerebral/fisiopatologia , Convulsões/genética , Transdução de Sinais , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Proteínas de Ciclo Celular , Córtex Cerebral/fisiologia , Células Ependimogliais/fisiologia , Deleção de Genes , Regulação da Expressão Gênica no Desenvolvimento , Predisposição Genética para Doença , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Tamanho do Órgão/genética , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Convulsões/fisiopatologia , Transdução de Sinais/genética , Células-Tronco/fisiologia , Transativadores , Proteínas de Sinalização YAP
3.
BMC Plant Biol ; 24(1): 596, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38914948

RESUMO

BACKGROUND: Cliffs are recognized as one of the most challenging environments for plants, characterized by harsh conditions such as drought, infertile soil, and steep terrain. However, they surprisingly host ancient and diverse plant communities and play a crucial role in protecting biodiversity. The Taihang Mountains, which act as a natural boundary in eastern China, support a rich variety of plant species, including many unique to cliff habitats. However, it is little known how cliff plants adapt to harsh habitats and the demographic history in this region. RESULTS: To better understand the demographic history and adaptation of cliff plants in this area, we analyzed the chromosome-level genome of a representative cliff plant, T. rupestris var. ciliata, which has a genome size of 769.5 Mb, with a scaffold N50 of 104.92 Mb. The rapid expansion of transposable elements may have contributed to the increasing genome and its ability to adapt to unique and challenging cliff habitats. Comparative analysis of the genome evolution between Taihangia and non-cliff plants in Rosaceae revealed a significant expansion of gene families associated with oxidative phosphorylation, which is likely a response to the abiotic stresses faced by cliff plants. This expansion may explain the long-term adaptation of Taihangia to harsh cliff environments. The effective population size of the two varieties has continuously decreased due to climatic fluctuations during the Quaternary period. Furthermore, significant differences in gene expression between the two varieties may explain the varied leaf phenotypes and adaptations to harsh conditions in different natural distributions. CONCLUSION: Our study highlights the extraordinary adaptation of T. rupestris var. ciliata, shedding light on the evolution of cliff plants worldwide.


Assuntos
Adaptação Fisiológica , Cromossomos de Plantas , Genoma de Planta , China , Cromossomos de Plantas/genética , Adaptação Fisiológica/genética , Rosaceae/genética , Rosaceae/fisiologia , Ecossistema , Evolução Molecular
4.
BMC Plant Biol ; 24(1): 476, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816799

RESUMO

BACKGROUND: Interest in the evolution of climatic niches, particularly in understanding the potential adaptive responses of species under climate change, has increased both theoretically and within macroecological studies. These studies have provided valuable insights into how climatic traits of species influence their niche evolution. In this study, we aim to investigate whether niche conservatism plays a role in the species diversification of Nymphaea, a group of aquatic plants with a cosmopolitan distribution that is facing severe habitat loss. We will use climatic models and phylogenetic data for 23 species to reconstruct Nymphaea's niche evolution, measure niche overlap, and assess disparity through time while testing for evolutionary models. RESULTS: There was a lot of overlap in niches both within and between groups, especially for species that can be found in many places. The breadth and peaks of the niche profile varied depending on the bioclimatic variables, which suggested that the species evolved differently to cope with changes in climate. The analysis also showed that evolutionary changes happened across the phylogeny, with weak to moderate signals. The morphological disparity index (MDI) values indicated that there were disparities within subclades over time but not between or among them. Niche reconstruction and evolution analysis revealed both convergent and divergent evolution among various variables. For example, N. immutabilis, N. atrans, N. violancea, and N. nouchali evolved towards intermediate temperatures for bio2 and bio3 (isothermity) while moving towards extreme temperatures for bio8 and bio9 (wettest and driest average quarterly temperatures). CONCLUSION: Our study will improve our understanding of how changes in climatic niches are potentially driving the evolution of Nymphaea. It has significant scientific implications for the limits, assemblages, evolution, and diversification of species. This information is crucial for the ongoing efforts of conservation and management, particularly considering the inevitable effects of climate change.


Assuntos
Evolução Biológica , Clima , Ecossistema , Filogenia , América do Sul , Austrália , África , Mudança Climática
5.
Mol Cell ; 64(4): 774-789, 2016 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-27840026

RESUMO

For many years, a connection between circadian clocks and cancer has been postulated. Here we describe an unexpected function for the circadian repressor CRY2 as a component of an FBXL3-containing E3 ligase that recruits T58-phosphorylated c-MYC for ubiquitylation. c-MYC is a critical regulator of cell proliferation; T58 is central in a phosphodegron long recognized as a hotspot for mutation in cancer. This site is also targeted by FBXW7, although the full machinery responsible for its turnover has remained obscure. CRY1 cannot substitute for CRY2 in promoting c-MYC degradation. Their unique functions may explain prior conflicting reports that have fueled uncertainty about the relationship between clocks and cancer. We demonstrate that c-MYC is a target of CRY2-dependent protein turnover, suggesting a molecular mechanism for circadian control of cell growth and a new paradigm for circadian protein degradation.


Assuntos
Transformação Celular Neoplásica/genética , Relógios Circadianos/genética , Criptocromos/genética , Proteínas F-Box/genética , Regulação Neoplásica da Expressão Gênica , Linfoma/genética , Proteínas Proto-Oncogênicas c-myc/genética , Animais , Proteínas de Transporte/química , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Ritmo Circadiano/genética , Criptocromos/química , Criptocromos/metabolismo , Proteínas Culina/química , Proteínas Culina/genética , Proteínas Culina/metabolismo , Proteínas F-Box/química , Proteínas F-Box/metabolismo , Fibroblastos , Células HEK293 , Humanos , Linfoma/metabolismo , Linfoma/mortalidade , Linfoma/patologia , Camundongos , Camundongos Knockout , Modelos Moleculares , Estabilidade Proteica , Estrutura Secundária de Proteína , Proteólise , Proteínas Proto-Oncogênicas c-myc/química , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas Quinases Associadas a Fase S/química , Proteínas Quinases Associadas a Fase S/genética , Proteínas Quinases Associadas a Fase S/metabolismo , Transdução de Sinais , Análise de Sobrevida
6.
Ergonomics ; 67(6): 866-880, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38770836

RESUMO

By conducting a mixed-design experiment using simplified accident handling tasks performed by two-person teams, this study examined the effects of automation function and condition (before, during, and after malfunction) on human performance. Five different and non-overlapping functions related to human information processing model were considered and their malfunctions were set in a first-failure way. The results showed that while the automation malfunction impaired task performance, the performance degradation for information analysis was more severe than response planning. Contrary to other functions, the situation awareness for response planning and response implementation tended to increase during malfunctioning and decrease after. In addition, decreased task performance reduced trust in automation, and malfunctions in earlier stages of information processing resulted in lower trust. Suggestions provided for the design and training related to automation emphasise the importance of high-level cognitive support and the benefit of involving automation error handling in training.


The effects of automation function and malfunction on human performance are important for design and training. The experimental results in this study revealed the significance of high-level cognitive support. Also, introducing automation error handling in training can be helpful in improving situation awareness of the teams.


Assuntos
Automação , Análise e Desempenho de Tarefas , Humanos , Masculino , Feminino , Adulto , Adulto Jovem , Sistemas Homem-Máquina , Confiança , Conscientização
7.
BMC Plant Biol ; 23(1): 125, 2023 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-36869282

RESUMO

BACKGROUND: The rapidly increasing availability of complete plastomes has revealed more structural complexity in this genome under different taxonomic levels than expected, and this complexity provides important evidence for understanding the evolutionary history of angiosperms. To explore the dynamic history of plastome structure across the subclass Alismatidae, we sampled and compared 38 complete plastomes, including 17 newly assembled, representing all 12 recognized families of Alismatidae. RESULT: We found that plastomes size, structure, repeat elements, and gene content were highly variable across the studied species. Phylogenomic relationships among families were reconstructed and six main patterns of variation in plastome structure were revealed. Among these, the inversion from rbcL to trnV-UAC (Type I) characterized a monophyletic lineage of six families, but independently occurred also in Caldesia grandis. Three independent ndh gene loss events were uncovered across the Alismatidae. In addition, we detected a positive correlation between the number of repeat elements and the size of plastomes and IR in Alismatidae. CONCLUSION: In our study, ndh complex loss and repeat elements likely contributed to the size of plastomes in Alismatidae. Also, the ndh loss was more likely related to IR boundary changes than the adaptation of aquatic habits. Based on existing divergence time estimation, the Type I inversion may have occurred during the Cretaceous-Paleogene in response to the extreme paleoclimate changes. Overall, our findings will not only allow exploring the evolutionary history of Alismatidae plastome, but also provide an opportunity to test if similar environmental adaptations result in convergent restructuring in plastomes.


Assuntos
Alismatales , Magnoliopsida , Aclimatação , Evolução Biológica , Filogenia
8.
New Phytol ; 240(5): 2058-2071, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37717220

RESUMO

Distyly has evolved independently in numerous animal-pollinated angiosperm lineages. Understanding of its molecular basis has been restricted to a few species, primarily Primula. Here, we investigate the genetic architecture of the single diallelic locus (S-locus) supergene, a linkage group of functionally associated genes, and explore how it may have evolved in distylous Nymphoides indica, a lineage of flowering plants not previously investigated. We assembled haplotype-resolved genomes, used read-coverage-based genome-wide association study (rb-GWAS) to locate the S-locus supergene, co-expression network analysis to explore gene networks underpinning the development of distyly, and comparative genomic analyses to investigate the origins of the S-locus supergene. We identified three linked candidate S-locus genes - NinBAS1, NinKHZ2, and NinS1 - that were only evident in the short-styled morph and were hemizygous. Co-expression network analysis suggested that brassinosteroids contribute to dimorphic sex organs in the short-styled morph. Comparative genomic analyses indicated that the S-locus supergene likely evolved via stepwise duplications and has been affected by transposable element activities. Our study provides novel insight into the structure, regulation, and evolution of the supergene governing distyly in N. indica. It also provides high-quality genomic resources for future research on the molecular mechanisms underlying the striking evolutionary convergence in form and function across heterostylous taxa.


Assuntos
Estudo de Associação Genômica Ampla , Primula , Haplótipos/genética , Primula/genética , Genômica , Flores/genética
9.
Ann Bot ; 131(3): 545-552, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-36655615

RESUMO

BACKGROUND AND AIMS: Allometric scaling between stomata and xylem for terrestrial woody plants is a widely observed pattern that may be constrained by water transport. Floating-leaved plants, a particular life form of aquatic plants, have leaves in direct contact with both air and water and a poorly developed xylem that may not be limited by water supply as for terrestrial plants. However, whether such an allometric scaling relationship still exists in floating-leaved plants has not been explored. METHODS: We analysed 31 floating-leaved species/varieties with a range in leaf area covering six orders of magnitude. For all 31 floating-leaved plants, we studied the allometric relationships between leaf area and petiole transverse area, and between total stomatal area and petiole vascular area. KEY RESULTS: The slopes of both relationships were similar to the slope of the allometric relationship (1.23) between total stomatal area and xylem area of 53 terrestrial plants. However, for ten of them with xylem that can be clearly defined, the strong positive relationship between total stomatal area and petiole xylem area had a significantly smaller slope than that of terrestrial plants (0.64 vs. 1.23). Furthermore, after considering phylogeny, the scaling relationships between total stomatal area and petiole traits in floating-leaved plants remained significant. CONCLUSIONS: We speculated that for floating-leaved plants, the hyperallometric relationship (slope >1) between the construction of leaf/stoma and petiole was promoted by the high demand for photosynthesis and thus more leaves/stomata. While the hypoallometric relationship (slope <1) between stomatal and xylem area was related more to hydraulic processes, the selection pressure on stomata was lower than xylem of floating-leaved plants. Allometric relationships among the hydraulic traits on water transport of aquatic plants are the result of natural selection to achieve maximum carbon gain, which is similar to terrestrial plants.


Assuntos
Folhas de Planta , Água , Aclimatação , Árvores , Xilema , Estômatos de Plantas
10.
J Hered ; 114(5): 570-579, 2023 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-37335172

RESUMO

Juglans californica, California walnut, is a vulnerable small tree that is locally abundant but restricted to woodland and chaparral habitats of Southern California threatened by urbanization and land use change. This species is the dominant species in a unique woodland ecosystem in California. It is one of 2 endemic California walnut species (family Juglandaceae). The other species, Northern California black walnut (J. hindsii), has been suggested controversially to be a variety of J. californica. Here, we report a new, chromosome-level assembly of J. californica as part of the California Conservation Genomics Project (CCGP). Consistent with the CCGP common methodology across ~150 genomes, we used Pacific Biosciences HiFi long reads and Omni-C chromatin-proximity sequencing technology to produce a de novo assembled genome. The assembly comprises 137 scaffolds spanning 551,065,703 bp, has a contig N50 of 30 Mb, a scaffold N50 of 37 Mb, and BUSCO complete score of 98.9%. Additionally, the mitochondrial genome has 701,569 bp. In addition, we compare this genome with other existing high-quality Juglans and Quercus genomes, which are in the same order (Fagales) and show relatively high synteny within the Juglans genomes. Future work will utilize the J. californica genome to determine its relationship with the Northern California walnut and assess the extent to which these 2 endemic trees might be at risk from fragmentation and/or climate warming.


Assuntos
Juglans , Juglans/genética , Ecossistema , Genoma , Genômica/métodos , California
11.
J Nanobiotechnology ; 21(1): 192, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37316835

RESUMO

In the treatment of spinal cord injury (SCI), the complex process of secondary injury is mainly responsible for preventing SCI repair or even exacerbating the injury. In this experiment, we constructed the 8-gingerol (8G)-loaded mesoporous polydopamine (M-PDA), M@8G, as the in vivo targeting nano-delivery platform, and investigated the therapeutic effects of M@8G in secondary SCI and its related mechanisms. The results indicated that M@8G could penetrate the blood-spinal cord barrier to enrich the spinal cord injury site. Mechanism research has shown that all of the M-PDA,8G and M@8G displayed the anti-lipid peroxidation effect, and then M@8G can inhibit the secondary SCI by suppressing the ferroptosis and inflammation. In vivo assays showed that M@8G significantly diminished the local injury area, reduced axonal and myelin loss, thus improving the neurological and motor recovery in rats. Based on the analysis of cerebrospinal fluid samples from patients, ferroptosis occurred locally in SCI and continued to progress in patients during the acute phase of SCI as well as the stage after their clinical surgery. This study showcases effective treatment of SCI through the aggregation and synergistic effect of M@8G in focal areas, providing a safe and promising strategy for the clinical treatment of SCI.


Assuntos
Traumatismos da Medula Espinal , Animais , Ratos , Traumatismos da Medula Espinal/tratamento farmacológico , Catecóis/farmacologia , Álcoois Graxos/farmacologia
12.
J Nurs Adm ; 53(9): 445-452, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37624807

RESUMO

OBJECTIVE: This project aims to identify the prevalence of acute care nurse leader turnover intention and the contributing factors. BACKGROUND: Previous research has identified that nurse leaders often quit around 1 year after stepping into a leadership position. More in-depth investigations of the phenomenon are needed. METHODS: The 2018 National Sample Survey of Registered Nurses data were used in this quantitative, cross-sectional study. The sample of nurse leaders was drawn from survey participants. Characteristics of interest in this study were listed in the survey questionnaire and divided into 5 categories: education, primary nursing employment, race, marital status, and age. RESULTS: A total of 50 273 participants completed the survey. The final sample size of nurse leaders was 1310 based on the eligibility criteria. The characteristics of the nurse leaders with turnover intention were reported in the 5 previously identified categories. Age, federally assisted student loans, and hours worked in a typical week predicted turnover intention. Low dissatisfaction and ability to practice to the full extent of knowledge, education, and training were strongly associated with nurse leader turnover intention. CONCLUSIONS: The study findings contribute to a more in-depth discovery of the causes of nurse leader turnover and future interventional research.


Assuntos
Hospitais , Intenção , Humanos , Prevalência , Estudos Transversais , Escolaridade
13.
Ergonomics ; 66(7): 927-938, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36036469

RESUMO

Information is key to the process of diagnosis, so it is necessary to understand how information amount may influence human performance. The current study investigated this issue through an experiment where participants diagnosed an accident in a simulated nuclear power plant. The amount of accessible information and the times of making judgments were manipulated. The results showed that increasing the amount of accessible information led the participants to seek more and think shallower, and thus decreased diagnostic accuracies, whereas no significant effects were found for multiple judgement times. The authors argue that the disadvantages of more accessible information could be attributed not simply to 'information overload', but partly to the diagnosticians' unwise choice of information processing strategies. The findings imply that system designers should restrain the ever-growing amount of information while users should make more efficient use of information rather than take in more.Practitioner summary: Current research on diagnosis by humans was mostly limited to outcome performance. This study empirically investigated factors influencing its detailed process. The results showed that increasing accessible information amount impaired both process and outcome performances.


Assuntos
Julgamento , Centrais Nucleares , Humanos , Cognição
14.
BMC Plant Biol ; 22(1): 106, 2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35260081

RESUMO

BACKGROUND: Hydrocharis L. and Limnobium Rich. are small aquatic genera, including three and two species, respectively. The taxonomic status, phylogenetic relationships and biogeographical history of these genera have remained unclear, owing to the lack of Central African endemic H. chevalieri from all previous studies. We sequenced and assembled plastomes of all three Hydrocharis species and Limnobium laevigatum to explore the phylogenetic and biogeographical history of these aquatic plants. RESULTS: All four newly generated plastomes were conserved in genome structure, gene content, and gene order. However, they differed in size, the number of repeat sequences, and inverted repeat borders. Our phylogenomic analyses recovered non-monophyletic Hydrocharis. The African species H. chevalieri was fully supported as sister to the rest of the species, and L. laevigatum was nested in Hydrocharis as a sister to H. dubia. Hydrocharis-Limnobium initially diverged from the remaining genera at ca. 53.3 Ma, then began to diversify at ca. 30.9 Ma. The biogeographic analysis suggested that Hydrocharis probably originated in Europe and Central Africa. CONCLUSION: Based on the phylogenetic results, morphological similarity and small size of the genera, the most reasonable taxonomic solution to the non-monophyly of Hydrocharis is to treat Limnobium as its synonym. The African endemic H. chevalieri is fully supported as a sister to the remaining species. Hydrocharis mainly diversified in the Miocene, during which rapid climate change may have contributed to the speciation and extinctions. The American species of former Limnobium probably dispersed to America through the Bering Land Bridge during the Miocene.


Assuntos
Organismos Aquáticos/classificação , Organismos Aquáticos/genética , Evolução Molecular , Genomas de Plastídeos , Hydrocharitaceae/classificação , Hydrocharitaceae/genética , Filogeografia , Europa (Continente)
15.
Mol Phylogenet Evol ; 166: 107334, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34715331

RESUMO

Alismataceae, an ancient lineage of monocots, has attracted attention due to its complex evolutionary history, ornamental value, and ecological role. However, the phylogenetic relationships and evolutionary history of the family have not been conclusively resolved. Here, we constructed the first complete genus-level plastid phylogeny of Alismataceae by using 78 genes and updated the historical biogeography based on the phylogenomic tree. Our results divide the Alismataceae into three major clades with robust support values; one clade comprises the former Limnocharitaceae, and the second clade includes the mainly temperate genera Alisma, Baldellia, Damasonium and Luronium, and the monotypic African genus Burnatia as a sister of the temperate genera. The remaining genera are either tropical or have some temperate species in addition to tropical ones, and they constitute the third major clade. Molecular dating and biogeographic analyses suggest that Alismataceae arose in Neotropical, West Palearctic, and Afrotropical regions during the Cretaceous, followed by the split into three main clades due to a combination of vicariance and dispersal events. Unlike earlier studies, we inferred that the mainly temperate clade likely originated from Afrotropical and West Palearctic regions during the Eocene. The most recent common ancestor of the other two clades lived in the Neotropical area during the Late Cretaceous. Long-distance dispersal and vicariance together seem to contribute to the transoceanic distribution of this family.


Assuntos
Alismataceae , Evolução Biológica , Filogenia , Filogeografia , Plastídeos/genética
16.
Mol Biol Rep ; 49(2): 917-929, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34741709

RESUMO

BACKGROUND: Understanding genetic variation is critical for the protection and maintenance of fragmented and highly disturbed habitats. The Taita Hills of Kenya are the northernmost part of the Eastern Arc Mountains and have been identified as one of the world's top ten biodiversity hotspots. Over the past century the current forests in the Taita Hills have become highly fragmented. In order to appraise the influence of anthropological disturbance and fragmentation on plant species in these mountains, we studied the genetic variation and population structure of Dodonaea viscosa (L.) Jacq. (Sapindaceae), using newly developed microsatellite (SSR) markers, combined with ecological niche modelling analyses (ENMs). METHODS AND RESULTS: We utilized the Illumina paired-end technology to sequence D. viscosa's genome and developed its microsatellite markers. In total, 646,428 sequences were analyzed, and 49,836 SSRs were identified from 42,638 sequences. A total of 18 out of 25 randomly selected primer pairs were designed to test polymorphism among 92 individuals across eight populations. The average observed heterozygosity and expected heterozygosity ranged from 0.119 to 0.982 and from 0.227 to 0.691, respectively. Analysis of molecular variance (AMOVA) revealed 78% variance within populations and only 20% among the eight populations. According to ENM results, D. viscosa's suitable habitats have been gradually reducing since the last glacial maximum (LGM), and the situation will worsen under the extreme pessimist scenario of (representative concentration pathway) RCP 8.5. Moreover, genetic diversity was significantly greater in larger fragments. CONCLUSIONS: In the present study, we successfully developed and tested SSR markers for D. viscosa. Study results indicate that fragmentation would constitute a severe threat to plant forest species. Therefore, urgent conservation management of smaller fragmented patches is necessary to protect this disturbed region and maintain the genetic resources.


Assuntos
Repetições de Microssatélites/genética , Sapindaceae/genética , Conservação dos Recursos Naturais , Florestas , Variação Genética/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Quênia , Polimorfismo Genético/genética
17.
Cell Mol Biol (Noisy-le-grand) ; 68(5): 207-212, 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-36029488

RESUMO

The study aimed to explore the correlations of the results of the high-frequency ultrasound evaluation of the brachial artery endothelial dilatation and carotid atherosclerosis with glucose and lipid metabolism, inflammatory cytokines, the severity of coronary artery disease (CAD) and vascular endothelial function in elderly patients. 78 elderly patients with CAD in Beijing Anzhen Hospital were selected. The high-frequency ultrasonography was carried out to observe the flow-mediated dilatation (FMD) and intima-media thickness (IMT) and to analyze their correlations with inflammatory cytokines [C-reactive protein (CRP) and plasminogen activator inhibitor (PAI-1)], endothelial function [nitric oxide (NO) and endothelin-1 (ET-1)], glycolipid metabolism [high-density lipoprotein cholesterol (HDL-C), total cholesterol (TC), triglyceride (TG) and fasting blood glucose (FBG)] and the severity of CAD. FMD, NO and HDL-C: patients with single-vesselCAD> those with double-vessel CAD>those with multi-vessel CAD. IMT, CRP, PAI-1, FBG, ET-1, TC and TG: patients with single-vesselCAD< those with double-vessel CAD

Assuntos
Doenças das Artérias Carótidas , Doença da Artéria Coronariana , Idoso , Artéria Braquial , Proteína C-Reativa , Artérias Carótidas , Espessura Intima-Media Carotídea , Colesterol , Citocinas , Dilatação , Endotélio Vascular , Glucose , Humanos , Metabolismo dos Lipídeos , Inibidor 1 de Ativador de Plasminogênio , Triglicerídeos , Ultrassonografia
18.
J Nanobiotechnology ; 20(1): 65, 2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35109874

RESUMO

Stem cell-derived exosomes have recently been regarded as potential drugs for treating spinal cord injury (SCI) by reducing reactive oxygen species (ROS) and suppressing M1 macrophage polarization. However, the roles of ROS and exosomes in the process of M1 macrophage polarization are not known. Herein, we demonstrated that ROS can induce M1 macrophage polarization and have a concentration-dependent effect. ROS can induce M1 macrophage polarization through the MAPK-NFκB P65 signaling pathway. Dental pulp stem cell (DPSC)-derived exosomes can reduce macrophage M1 polarization through the ROS-MAPK-NFκB P65 signaling pathway in treating SCI. This study suggested that DPSC-derived exosomes might be a potential drug for treating SCI. Disruption of the cycle between ROS and M1 macrophage polarization might also be a potential effective treatment by reducing secondary damage.


Assuntos
Exossomos , Traumatismos da Medula Espinal , Polpa Dentária , Exossomos/metabolismo , Humanos , Macrófagos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/terapia , Células-Tronco
19.
Mol Biol Evol ; 37(8): 2394-2413, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32343808

RESUMO

For most sequenced flowering plants, multiple whole-genome duplications (WGDs) are found. Duplicated genes following WGD often have different fates that can quickly disappear again, be retained for long(er) periods, or subsequently undergo small-scale duplications. However, how different expression, epigenetic regulation, and functional constraints are associated with these different gene fates following a WGD still requires further investigation due to successive WGDs in angiosperms complicating the gene trajectories. In this study, we investigate lotus (Nelumbo nucifera), an angiosperm with a single WGD during the K-pg boundary. Based on improved intraspecific-synteny identification by a chromosome-level assembly, transcriptome, and bisulfite sequencing, we explore not only the fundamental distinctions in genomic features, expression, and methylation patterns of genes with different fates after a WGD but also the factors that shape post-WGD expression divergence and expression bias between duplicates. We found that after a WGD genes that returned to single copies show the highest levels and breadth of expression, gene body methylation, and intron numbers, whereas the long-retained duplicates exhibit the highest degrees of protein-protein interactions and protein lengths and the lowest methylation in gene flanking regions. For those long-retained duplicate pairs, the degree of expression divergence correlates with their sequence divergence, degree in protein-protein interactions, and expression level, whereas their biases in expression level reflecting subgenome dominance are associated with the bias of subgenome fractionation. Overall, our study on the paleopolyploid nature of lotus highlights the impact of different functional constraints on gene fate and duplicate divergence following a single WGD in plant.


Assuntos
Metilação de DNA , Duplicação Gênica , Genoma de Planta , Nelumbo/genética , Poliploidia , Cromossomos de Plantas
20.
J Neuroinflammation ; 18(1): 64, 2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33653377

RESUMO

BACKGROUND: Immune cell infiltration and neuroinflammation are heavily associated with spinal cord injury (SCI). C-C motif chemokine ligand 2/C-C chemokine receptor type 2 (CCL2/CCR2) axis has been identified as a critical role player during the invasion of immune cells to lesions in many diseases. γδ T cells, a subgroup of T cells, manage the course of inflammation response in various diseases; however, it remains unknown whether γδ T cells are recruited to injury site through CCL2/CCR2 signaling and exert the regulation effect on neuroinflammation after SCI. METHODS: Basso Mouse Scale (BMS), regularity index, cadence, max contact area, and motor-evoked potential testing (MEP) were measured to determine the neurological function recovery after spinal cord injury. Nissl staining was performed to identify the number of surviving motor neurons at lesion epicenter. Immunofluorescence, Western blot, enzyme-linked immunosorbent assays (ELISA), and quantitative real-time polymerase chain reaction (QRT-PCR) also were employed to evaluate the expression of associated proteins and genes. RESULTS: In this study, we demonstrated that TCRδ-/- mice present improved neurological recovery after SCI. γδ T cell recruitment to the SCI site was significantly reduced and motor functional improvement enhanced in CCL2-/- and CCR2-/- mouse strains. Furthermore, reconstitution of TCRδ-/- mice with γδ T cells extracted from CCR2-/- mice also showed similar results to CCL2 and CCR2 deficient mice. CONCLUSIONS: In conclusion, γδ T cell recruitment to SCI site promotes inflammatory response and exacerbates neurological impairment. CCL2/CCR2 signaling is a vital recruitment mechanism of γδ T cells to the SCI site, and it may be taken as a novel therapeutic target for future SCI.


Assuntos
Quimiocina CCL2/imunologia , Receptores CCR2/imunologia , Transdução de Sinais/imunologia , Traumatismos da Medula Espinal/imunologia , Linfócitos T/imunologia , Animais , Quimiocina CCL2/metabolismo , Quimiotaxia de Leucócito/imunologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Receptores CCR2/metabolismo , Traumatismos da Medula Espinal/patologia , Linfócitos T/metabolismo
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