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1.
Mol Biol Evol ; 41(6)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38768215

RESUMO

High mountains harbor a considerable proportion of biodiversity, but we know little about how diverse plants adapt to the harsh environment. Here we finished a high-quality genome assembly for Dasiphora fruticosa, an ecologically important plant distributed in the Qinghai-Tibetan Plateau and lowland of the Northern Hemisphere, and resequenced 592 natural individuals to address how this horticulture plant adapts to highland. Demographic analysis revealed D. fruticosa underwent a bottleneck after Naynayxungla Glaciation. Selective sweep analysis of two pairs of lowland and highland populations identified 63 shared genes related to cell wall organization or biogenesis, cellular component organization, and dwarfism, suggesting parallel adaptation to highland habitats. Most importantly, we found that stronger purging of estimated genetic load due to inbreeding in highland populations apparently contributed to their adaptation to the highest mountain. Our results revealed how plants could tolerate the extreme plateau, which could provide potential insights for species conservation and crop breeding.


Assuntos
Genoma de Planta , Seleção Genética , Adaptação Fisiológica/genética , Altitude
2.
New Phytol ; 235(1): 276-291, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35118662

RESUMO

Sea buckthorn (Hippophae rhamnoides), a horticulturally multipurpose species in the family Elaeagnaceae, can build associations with Frankia actinomycetes to enable symbiotic nitrogen-fixing. Currently, no high-quality reference genome is available for an actinorhizal plant, which greatly hinders the study of actinorhizal symbiotic nodulation. Here, by combining short-read, long-read and Hi-C sequencing technologies, we generated a chromosome-level reference genome of H. rhamnoides (scaffold N50: 65 Mb, and genome size: 730 Mb) and predicted 30 812 protein-coding genes mainly on 12 pseudochromosomes. Hippophae rhamnoides was found to share a high proportion of symbiotic nodulation genes with Medicago truncatula, implying a shared molecular mechanism between actinorhizal and rhizobial symbioses. Phylogenetic analysis clustered the three paralogous NODULE INCEPTION (NIN) genes of H. rhamnoides with those of other nodulating species, forming the NIN group that most likely evolved from the ancestral NLP group. The genome of H. rhamnoides will help us to decipher the underlying genetic programming of actinorhizal symbiosis, and our high-quality genome and transcriptomic resources will make H. rhamnoides a new excellent model plant for actinorhizal symbiosis research.


Assuntos
Frankia , Hippophae , Rhizobium , Frankia/genética , Hippophae/genética , Filogenia , Plantas , Rhizobium/genética , Simbiose/genética
3.
New Phytol ; 234(1): 295-310, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34997964

RESUMO

Clarifying the evolutionary processes underlying species diversification and adaptation is a key focus of evolutionary biology. Begonia (Begoniaceae) is one of the most species-rich angiosperm genera with c. 2000 species, most of which are shade-adapted. Here, we present chromosome-scale genome assemblies for four species of Begonia (B. loranthoides, B. masoniana, B. darthvaderiana and B. peltatifolia), and whole genome shotgun data for an additional 74 Begonia representatives to investigate lineage evolution and shade adaptation of the genus. The four genome assemblies range in size from 331.75 Mb (B. peltatifolia) to 799.83 Mb (B. masoniana), and harbor 22 059-23 444 protein-coding genes. Synteny analysis revealed a lineage-specific whole-genome duplication (WGD) that occurred just before the diversification of Begonia. Functional enrichment of gene families retained after WGD highlights the significance of modified carbohydrate metabolism and photosynthesis possibly linked to shade adaptation in the genus, which is further supported by expansions of gene families involved in light perception and harvesting. Phylogenomic reconstructions and genomics studies indicate that genomic introgression has also played a role in the evolution of Begonia. Overall, this study provides valuable genomic resources for Begonia and suggests potential drivers underlying the diversity and adaptive evolution of this mega-diverse clade.


Assuntos
Begoniaceae , Begoniaceae/genética , Evolução Molecular , Genoma , Filogenia , Sintenia/genética
4.
Plant Cell Physiol ; 59(10): 1990-2003, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30137600

RESUMO

The tung tree (Vernicia fordii) is one of only a few plant species that produces high oil-yielding seeds rich in α-eleostearic acid (α-ESA, 18:3Δ9cis, 11trans, 13trans), a conjugated trienoic fatty acid with valuable industrial and medical properties. Previous attempts have been made to engineer tung oil biosynthesis in transgenic oilseed crops, but these efforts have met with limited success. Here we present a high-quality genome assembly and developing seed transcriptomic data set for this species. Whole-genome shotgun sequencing generated 176 Gb of genome sequence data used to create a final assembled sequence 1,176,320 kb in size, with a scaffold N50 size of >474 kb, and containing approximately 47,000 protein-coding genes. Genomic and transcriptomic data revealed full-length candidate genes for most of the known and suspected reactions that are necessary for fatty acid desaturation/conjugation, acyl editing and triacylglycerol biosynthesis. Seed transcriptomic analyses also revealed features unique to tung tree, including unusual transcriptional profiles of fatty acid biosynthetic genes, and co-ordinated (and seemingly paradoxical) simultaneous up-regulation of both fatty acid ß-oxidation and triacylglycerol biosynthesis in mid-development seeds. The precise temporal control of the expression patterns for these two pathways may account for α-ESA enrichment in tung seeds, while controlling the levels of potentially toxic by-products. Deeper understanding of these processes may open doors to the design of engineered oilseeds containing high levels of α-ESA.


Assuntos
Genoma de Planta/genética , Ácidos Linolênicos/metabolismo , Sementes/metabolismo , Transcriptoma/genética , Triglicerídeos/biossíntese , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia
5.
J Immunol ; 196(12): 5138-47, 2016 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-27183632

RESUMO

Although evolutionarily just as ancient as IgM, it has been thought for many years that IgD is not present in birds. Based on the recently sequenced genomes of 48 bird species as well as high-throughput transcriptome sequencing of immune-related tissues, we demonstrate in this work that the ostrich (Struthio camelus) possesses a functional δ gene that encodes a membrane-bound IgD H chain with seven CH domains. Furthermore, δ sequences were clearly identified in many other bird species, demonstrating that the δ gene is widely distributed among birds and is only absent in certain bird species. We also show that the ostrich possesses two µ genes (µ1, µ2) and two υ genes (υ1, υ2), in addition to the δ and α genes. Phylogenetic analyses suggest that subclass diversification of both the µ and υ genes occurred during the early stages of bird evolution, after their divergence from nonavian reptiles. Although the positions of the two υ genes are unknown, physical mapping showed that the remaining genes are organized in the order µ1-δ-α-µ2, with the α gene being inverted relative to the others. Together with previous studies, our data suggest that birds and nonavian reptile species most likely shared a common ancestral IgH gene locus containing a δ gene and an inverted α gene. The δ gene was then evolutionarily lost in selected birds, whereas the α gene lost in selected nonavian reptiles. The data obtained in this study provide significant insights into the understanding of IgH gene evolution in tetrapods.


Assuntos
Evolução Molecular , Genes de Imunoglobulinas , Imunoglobulina D/genética , Imunoglobulina M/genética , Imunoglobulinas/genética , Struthioniformes/imunologia , Animais , Evolução Biológica , Aves/genética , Aves/imunologia , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Imunoglobulina D/imunologia , Imunoglobulina M/classificação , Cadeias delta de Imunoglobulina/genética , Imunoglobulinas/classificação , Filogenia , Répteis/genética , Répteis/imunologia , Alinhamento de Sequência , Struthioniformes/genética
6.
BMC Biol ; 14: 1, 2016 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-26728391

RESUMO

BACKGROUND: An emerging cavefish model, the cyprinid genus Sinocyclocheilus, is endemic to the massive southwestern karst area adjacent to the Qinghai-Tibetan Plateau of China. In order to understand whether orogeny influenced the evolution of these species, and how genomes change under isolation, especially in subterranean habitats, we performed whole-genome sequencing and comparative analyses of three species in this genus, S. grahami, S. rhinocerous and S. anshuiensis. These species are surface-dwelling, semi-cave-dwelling and cave-restricted, respectively. RESULTS: The assembled genome sizes of S. grahami, S. rhinocerous and S. anshuiensis are 1.75 Gb, 1.73 Gb and 1.68 Gb, respectively. Divergence time and population history analyses of these species reveal that their speciation and population dynamics are correlated with the different stages of uplifting of the Qinghai-Tibetan Plateau. We carried out comparative analyses of these genomes and found that many genetic changes, such as gene loss (e.g. opsin genes), pseudogenes (e.g. crystallin genes), mutations (e.g. melanogenesis-related genes), deletions (e.g. scale-related genes) and down-regulation (e.g. circadian rhythm pathway genes), are possibly associated with the regressive features (such as eye degeneration, albinism, rudimentary scales and lack of circadian rhythms), and that some gene expansion (e.g. taste-related transcription factor gene) may point to the constructive features (such as enhanced taste buds) which evolved in these cave fishes. CONCLUSION: As the first report on cavefish genomes among distinct species in Sinocyclocheilus, our work provides not only insights into genetic mechanisms of cave adaptation, but also represents a fundamental resource for a better understanding of cavefish biology.


Assuntos
Adaptação Fisiológica , Cyprinidae/genética , Cyprinidae/fisiologia , Evolução Molecular , Animais , Evolução Biológica , Cavernas , China , Cyprinidae/anatomia & histologia , Olho/anatomia & histologia , Olho/metabolismo , Olho/ultraestrutura , Regulação da Expressão Gênica , Genoma , Audição , Mutação , Filogenia , Dinâmica Populacional , Paladar
7.
BMC Genomics ; 15: 956, 2014 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-25373334

RESUMO

BACKGROUND: 2b-RAD (type IIB endonucleases restriction-site associated DNA) approach was invented by Wang in 2012 and proven as a simple and flexible method for genome-wide genotyping. However, there is still plenty of room for improvement for the existent 2b-RAD approach. Firstly, it doesn't include the samples pooling in library preparation as other reduced representation libraries. Secondly, the information of 2b-RAD tags, such as tags numbers and distributions, in most of species are unknown. The purposes of the research are to improve a new 2b-RAD approach which possesses samples pooling, moreover to figure out the characteristic and application potentiality of 2b-RAD tags by bioinformatics analysis. RESULTS: Twelve adapter1 and an adapter2 were designed. A library approach comprising digestion, ligation, pooling, PCR and size selection were established. For saving costs, we used non-phosphorylated adapters and indexed PCR primers. A F2 population of rice (Oryza sativa .L) was genotyped to validate the new approach. On average, 2000332 high quality reads of each sample were obtained with high evenness. Totally 3598 markers containing 3804 SNPs were discovered and the missing rate was 18.9%. A genetic linkage map of 1385 markers was constructed and 92% of the markers' orders in the genetic map were in accordance with the orders in chromosomes. Meanwhile, the bioinformatics simulation in 20 species showed that the BsaXI had the most widespread recognition sites, indicating that 2b-RAD tags had a powerful application potentiality for high density genetic map. Using modified adapters with a fix base in 3'end, 2b-RAD was also fit for QTL studies with low costs. CONCLUSIONS: An improved 2b-RAD genotyping approach was established in this research and named as I2b-RAD. The method was a simple, fast, cost-effective and multiplex sequencing library approach. It could be adjusted by selecting different enzymes and adapters to fit for alternative uses including chromosomes assembly, QTL fine mapping and even natural population analysis.


Assuntos
Cruzamentos Genéticos , Enzimas de Restrição do DNA/metabolismo , DNA de Plantas/genética , Técnicas de Genotipagem/métodos , Oryza/genética , Mapeamento Cromossômico , Simulação por Computador , Marcadores Genéticos , Padrões de Referência
8.
Sci Data ; 11(1): 554, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816414

RESUMO

Warburgia ugandensis and Saururus chinensis are two of the most important medicinal plants in magnoliids and are widely utilized in traditional Kenya and Chinese medicine, respectively. The absence of higher-quality reference genomes has hindered research on the medicinal compound biosynthesis mechanisms of these plants. We report the chromosome-level genome assemblies of W. ugandensis and S. chinensis, and generated 1.13 Gb and 0.53 Gb genomes from 74 and 27 scaffolds, respectively, using BGI-DIPSEQ, Nanopore, and Hi-C sequencing. The scaffold N50 lengths were 82.97 Mb and 48.53 Mb, and the assemblies were anchored to 14 and 11 chromosomes of W. ugandensis and S. chinensis, respectively. In total, 24,739 and 20,561 genes were annotated, and 98.5% and 98% of the BUSCO genes were fully represented, respectively. The chromosome-level genomes of W. ugandensis and S. chinensis will be valuable resources for understanding the genetics of these medicinal plants, studying the evolution of magnoliids and angiosperms and conserving plant genetic resources.


Assuntos
Genoma de Planta , Plantas Medicinais , Plantas Medicinais/genética , Cromossomos de Plantas/genética , Saururaceae/genética
9.
Front Plant Sci ; 14: 1252862, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37900750

RESUMO

The subtropical regions in China are prone to recurrent summer droughts induced by the Western Pacific Subtropical High-Pressure, which has induced the death of tens of millions of culms of Moso bamboo (Phyllostachys edulis (Carriere) J. Houzeau), a widely distributed giant bamboo with high economic and ecological values. In the future, the intensity and frequency of the summer drought are projected to increase in these areas due to global climate change, which may lead to significant age-specific mortality of Moso bamboo. So far, it is still unclear about the age-specific response mechanisms of hydraulic traits and carbon balance of Moso bamboo when it is suffering to an ongoing summer drought. This study aimed to investigate the hydraulic and photosynthetic responses of newly sprouted (1 year old) and established (2-5 years old) culms of Moso bamboo to summer drought, which was manipulated by throughfall reduction in Lin'an of Zhejiang. The results showed that both newly sprouted and established culms had a gradually weakening hydraulic conductivity and photosynthesis during the whole drought process. In the early stage of the manipulated drought, the established culms had more loss of hydraulic conductivity than the newly sprouted culms. However, the newly sprouted culms had significant more loss of hydraulic conductivity and lower photosynthetic rates and stomatal conductance in the middle and late stages of the manipulated drought. The results suggest that the newly sprouted culms were more susceptible to summer drought than established culms due to the combined effects of hydraulic damage and photosynthetic restriction, explaining why the newly sprouted culms have higher mortality than elder culms when subjected to extreme drought. These findings provided insights into the mechanisms of Moso bamboo's age-specific drought-induced mortality, which will help for the anti-drought management of bamboo.

10.
Front Plant Sci ; 14: 1154232, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37152132

RESUMO

Stem respiration (R s) plays a vital role in ecosystem carbon cycling. However, the measured efflux on the stem surface (E s) is not always in situ R s but only part of it. A previously proposed mass balance framework (MBF) attempted to explore the multiple partitioning pathways of R s, including sap-flow-transported and internal storage of R s, in addition to E s. This study proposed stem photosynthesis as an additional partitioning pathway to the MBF. Correspondingly, a double-chamber apparatus was designed and applied on newly sprouted Moso bamboo (Phyllostachys edulis) in leafless and leaved stages. R s of newly sprouted bamboo were twice as high in the leafless stage (7.41 ± 2.66 µmol m-2 s-1) than in the leaved stage (3.47 ± 2.43 µmol m-2 s-1). E s accounted for ~80% of R s, while sap flow may take away ~2% of R s in both leafless and leaved stages. Culm photosynthesis accounted for ~9% and 13% of R s, respectively. Carbon sequestration from culm photosynthesis accounted for approximately 2% of the aboveground bamboo biomass in the leafless stage. High culm photosynthesis but low sap flow during the leafless stage and vice versa during the leaved stage make bamboo an outstanding choice for exploring the MBF.

11.
BMC Complement Med Ther ; 23(1): 194, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37308900

RESUMO

BACKGROUND: Rosenroot (Rhodiola rosea) is a traditional Chinese herbal medicine. It has been used to treat patients with coronary artery disease (CAD). Salidroside is the main active constituent of rosenroot. This study was designed to explore the mechanism of salidroside in treating CAD and its role in angiogenesis in CAD systematically. METHODS: In this study, potential targets related to salidroside and CAD were obtained from public databases. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), Disease Ontology (DO) and CellMarker enrichment analyses were performed. The binding of salidroside to angiogenesis-related targets was assessed by PyMOL and Ligplot. Furthermore, the effects of salidroside on collateral circulation were evaluated by correlation analysis of these angiogenesis-related targets with the coronary flow index (CFI), and the influence of salidroside on human umbilical vein endothelial cell (HUVEC) proliferation and migration was assessed. RESULTS: Eighty-three targets intersected between targets of salidroside and CAD. GO and KEGG analyses indicated that salidroside mainly treated CAD through angiogenesis and anti-inflammatory action. There were 12 angiogenesis-related targets of salidroside in coronary heart disease, among which FGF1 (r = 0.237, P = 2.597E-3), KDR (r = 0.172, P = 3.007E-2) and HIF1A (r = -0.211, P = 7.437E-3) were correlated with the coronary flow index (CFI), and salidroside docked well with them. Finally, cell experiments confirmed that salidroside promoted the proliferation and migration of HUVECs. CONCLUSIONS: This study revealed the potential molecular mechanism of salidroside on angiogenesis in CAD and provided new ideas for the clinical application of salidroside in the treatment of CAD.


Assuntos
Doença da Artéria Coronariana , Glucosídeos , Glucosídeos/farmacologia , Glucosídeos/uso terapêutico , Doença da Artéria Coronariana/tratamento farmacológico , Angiogênese/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Células Endoteliais da Veia Umbilical Humana , Células Cultivadas
12.
Nat Commun ; 14(1): 3662, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37339966

RESUMO

Acorales is the sister lineage to all the other extant monocot plants. Genomic resource enhancement of this genus can help to reveal early monocot genomic architecture and evolution. Here, we assemble the genome of Acorus gramineus and reveal that it has ~45% fewer genes than the majority of monocots, although they have similar genome size. Phylogenetic analyses based on both chloroplast and nuclear genes consistently support that A. gramineus is the sister to the remaining monocots. In addition, we assemble a 2.2 Mb mitochondrial genome and observe many genes exhibit higher mutation rates than that of most angiosperms, which could be the reason leading to the controversies of nuclear genes- and mitochondrial genes-based phylogenetic trees existing in the literature. Further, Acorales did not experience tau (τ) whole-genome duplication, unlike majority of monocot clades, and no large-scale gene expansion is observed. Moreover, we identify gene contractions and expansions likely linking to plant architecture, stress resistance, light harvesting, and essential oil metabolism. These findings shed light on the evolution of early monocots and genomic footprints of wetland plant adaptations.


Assuntos
Acorus , Magnoliopsida , Acorus/genética , Filogenia , Genes de Plantas , Genômica , Cloroplastos/genética , Evolução Molecular , Genoma de Planta/genética , Magnoliopsida/genética
13.
Sci Data ; 10(1): 832, 2023 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-38007506

RESUMO

Mahogany species (family Meliaceae) are highly valued for their aesthetic and durable wood. Despite their economic and ecological importance, genomic resources for mahogany species are limited, hindering genetic improvement and conservation efforts. Here we perform chromosome-scale genome assemblies of two commercially important mahogany species: Swietenia macrophylla and Khaya senegalensis. By combining 10X sequencing and Hi-C data, we assemble high-quality genomes of 274.49 Mb (S. macrophylla) and 406.50 Mb (K. senegalensis), with scaffold N50 lengths of 8.51 Mb and 7.85 Mb, respectively. A total of 99.38% and 98.05% of the assembled sequences are anchored to 28 pseudo-chromosomes in S. macrophylla and K. senegalensis, respectively. We predict 34,129 and 31,908 protein-coding genes in S. macrophylla and K. senegalensis, respectively, of which 97.44% and 98.49% are functionally annotated. The chromosome-scale genome assemblies of these mahogany species could serve as a vital genetic resource, especially in understanding the properties of non-model woody plants. These high-quality genomes could support the development of molecular markers for breeding programs, conservation efforts, and the sustainable management of these valuable forest resources.


Assuntos
Genoma de Planta , Meliaceae , Cromossomos , Meliaceae/genética
14.
Nat Plants ; 9(10): 1627-1642, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37735254

RESUMO

Parasitic plants have evolved to be subtly or severely dependent on host plants to complete their life cycle. To provide new insights into the biology of parasitic plants in general, we assembled genomes for members of the sandalwood order Santalales, including a stem hemiparasite (Scurrula) and two highly modified root holoparasites (Balanophora) that possess chimaeric host-parasite tubers. Comprehensive genome comparisons reveal that hemiparasitic Scurrula has experienced a relatively minor degree of gene loss compared with autotrophic plants, consistent with its moderate degree of parasitism. Nonetheless, patterns of gene loss appear to be substantially divergent across distantly related lineages of hemiparasites. In contrast, Balanophora has experienced substantial gene loss for the same sets of genes as an independently evolved holoparasite lineage, the endoparasitic Sapria (Malpighiales), and the two holoparasite lineages experienced convergent contraction of large gene families through loss of paralogues. This unprecedented convergence supports the idea that despite their extreme and strikingly divergent life histories and morphology, the evolution of these and other holoparasitic lineages can be shaped by highly predictable modes of genome reduction. We observe substantial evidence of relaxed selection in retained genes for both hemi- and holoparasitic species. Transcriptome data also document unusual and novel interactions between Balanophora and host plants at the host-parasite tuber interface tissues, with evidence of mRNA exchange, substantial and active hormone exchange and immune responses in parasite and host.


Assuntos
Interações Hospedeiro-Parasita , Plantas , Interações Hospedeiro-Parasita/genética , Plantas/genética
15.
Sci Data ; 10(1): 512, 2023 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-37537171

RESUMO

Wood is the most important natural and endlessly renewable source of energy. Despite the ecological and economic importance of wood, many aspects of its formation have not yet been investigated. We performed chromosome-scale genome assemblies of three timber trees (Ochroma pyramidale, Mesua ferrea, and Tectona grandis) which exhibit different wood properties such as wood density, hardness, growth rate, and fiber cell wall thickness. The combination of 10X, stLFR, Hi-Fi sequencing and HiC data led us to assemble high-quality genomes evident by scaffold N50 length of 55.97 Mb (O. pyramidale), 22.37 Mb (M. ferrea) and 14.55 Mb (T. grandis) with >97% BUSCO completeness of the assemblies. A total of 35774, 24027, and 44813 protein-coding genes were identified in M. ferrea, T. grandis and O. pyramidale, respectively. The data generated in this study is anticipated to serve as a valuable genetic resource and will promote comparative genomic analyses, and it is of practical importance in gaining a further understanding of the wood properties in non-model woody species.


Assuntos
Bombacaceae , Genoma de Planta , Bombacaceae/genética , Cromossomos , Árvores/genética , Madeira/genética
16.
Sensors (Basel) ; 12(8): 10292-308, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23112600

RESUMO

Based on the magnetic resonance coupling principle, in this paper a wireless energy transfer system is designed and implemented for the power supply of micro-implantable medical sensors. The entire system is composed of the in vitro part, including the energy transmitting circuit and resonant transmitter coils, and in vivo part, including the micro resonant receiver coils and signal shaping chip which includes the rectifier module and LDO voltage regulator module. Transmitter and receiver coils are wound by Litz wire, and the diameter of the receiver coils is just 1.9 cm. The energy transfer efficiency of the four-coil system is greatly improved compared to the conventional two-coil system. When the distance between the transmitter coils and the receiver coils is 1.5 cm, the transfer efficiency is 85% at the frequency of 742 kHz. The power transfer efficiency can be optimized by adding magnetic enhanced resonators. The receiving voltage signal is converted to a stable output voltage of 3.3 V and a current of 10 mA at the distance of 2 cm. In addition, the output current varies with changes in the distance. The whole implanted part is packaged with PDMS of excellent biocompatibility and the volume of it is about 1 cm(3).


Assuntos
Espectroscopia de Ressonância Magnética/instrumentação , Próteses e Implantes , Processamento de Sinais Assistido por Computador/instrumentação , Telemedicina/instrumentação , Telemetria/instrumentação , Desenho de Equipamento , Modelos Teóricos
17.
Sensors (Basel) ; 12(4): 5105-15, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22666077

RESUMO

The steady-state zero output of static electric field measuring systems often fluctuates, which is caused mainly by the finite leakage resistance of the water film on the surface of the electric field microsensor package. The water adsorption has been calculated using the Boltzmann distribution equation at various relative humidities for borosilicate glass and polytetrafluoroethylene surfaces. At various humidities, water film thickness has been calculated, and the induced charge leakage and field attenuation have been theoretically investigated. Experiments have been performed with microsensors to verify the theoretical predictions and the results are in good agreement.

18.
Front Plant Sci ; 13: 1001785, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36247638

RESUMO

In recent decades, Moso bamboo has been largely increasing in the subtropical area of China, raising ecological concerns about its invasion into other native forest ecosystems. One concern is whether the invasion of Moso bamboo significantly simplifies forest community composition and structure and declines biomass. This study adopted the space-for-time method to investigate a secondary coniferous and broad-leaved mixed forest (SF) being invaded by an adjacent Moso bamboo forest (MB) in the Wuxie forest reserve, Zhejiang Province. Three plots were established in each SF, MB, and transitional forest. The results showed that the species composition and species dominance of the arborous layer changed significantly (P < 0.05), which was indicated by the significantly decreased species richness (Margalef index, Shannon-Wiener index, and Simpson index) and evenness (Pielou evenness index). In contrast, the species richness of the shrub and herbaceous layers had two divergent indications (increasing or unchanged), and the evenness remained unchanged. The total and arborous-layer aboveground biomass of the forest community has had no noticeable change (P < 0.05). However, the biomass of the shrub and herbaceous layers showed an increasing trend (shrub significant but herbaceous not), but they only occupied a small proportion (∼1%) of the total biomass. Finally, the aboveground biomass and the diversity index had no significant correlation in each layer and overall stands. We hope that the findings could provide a theoretical basis for the invasion mechanism and ecological consequences of the Moso bamboo invasion.

19.
Front Plant Sci ; 13: 846697, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35712591

RESUMO

MADS-box is an important transcription factor family that is involved in the regulation of various stages of plant growth and development, especially flowering regulation and flower development. Being a holoparasitic plant, the body structure of Balanophoraceae has changed dramatically over time, and its vegetative and reproductive organs have been extensively modified, with rudimentary flower organs. Meanwhile, extraordinary gene losses have been identified in holoparasitic plants compared with autotrophs. Our study reveals that the MADS-box gene family contracted sharply in Balanophora subcupularis and Balanophora fungosa var. globosa, and some subfamilies were lost, exhibiting reduced redundancy in both. The genes that functioned in the transition from the vegetative to floral production stages suffered a significant loss, but the ABCE model genes remained intact. We further investigated genes related to flowering regulation in B. subcupularis and B. fungosa var. globosa, vernalization and autonomous ways of regulating flowering time remained comparatively integrated, while genes in photoperiod and circadian clock pathways were almost lost. Convergent gene loss in flowering regulation occurred in Balanophora and another holoparasitic plant Sapria himalayana (Rafflesiaceae). The genome-wide analysis of the MADS-box gene family in Balanophora species provides valuable information for understanding the classification, gene loss pattern, and flowering regulation mechanism of MADS-box gene family in parasitic plants.

20.
Commun Biol ; 5(1): 1294, 2022 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-36434059

RESUMO

Cremastra appendiculata (D. Don) Makino is a rare terrestrial orchid with a high market value as an ornamental and Chinese traditional medicinal herb with a wide range of pharmacological properties. The pseudobulbs of C. appendiculata are one of the primary sources of the famous traditional Chinese medicine "Shancigu", which has been clinically used for treating many diseases, especially, as the main component to treat gout. The lack of genetic research and genome data restricts the modern development and clinical use of C. appendiculata. Here, we report a 2.3 Gb chromosome-level genome of C. appendiculata. We identify a series of candidates of 35 candidate genes responsible for colchicine biosynthesis, among which O-methyltransferase (OMT) gene exhibits an important role in colchicine biosynthesis. Co-expression analysis reveal purple and green-yellow module have close relationships with pseudobulb parts and comprise most of the colchicine pathway genes. Overall, our genome data and the candidate genes reported here set the foundation to decipher the colchicine biosynthesis pathways in medicinal plants.


Assuntos
Orchidaceae , Plantas Medicinais , Plantas Medicinais/genética , Vias Biossintéticas/genética , Colchicina/farmacologia , Orchidaceae/genética , Medicina Tradicional Chinesa
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