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1.
Mol Phylogenet Evol ; 196: 108084, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38688440

RESUMO

The tribe Collabieae (Epidendroideae, Orchidaceae) comprises approximately 500 species. Generic delimitation within Collabieae are confusing and phylogenetic interrelationships within the Collabieae have not been well resolved. Plastid genomes and nuclear internal transcribed spacer (ITS) sequences were used to estimate the phylogenetic relationships, ancestral ranges, and diversification rates of Collabieae. The results showed that Collabieae was subdivided into nine clades with high support. We proposed to combine Ancistrochilus and Pachystoma into Spathoglottis, merge Collabium and Chrysoglossum into Diglyphosa, and separate Pilophyllum and Hancockia as distinctive genera. The diversification of the nine clades of Collabieae might be associated with the uplift of the Himalayas during the Late Oligocene/Early Miocene. The enhanced East Asian summer monsoon in the Late Miocene may have promoted the rapid diversification of Collabieae at a sustained high diversification rate. The increased size of terrestrial pseudobulbs may be one of the drivers of Collabieae diversification. Our results suggest that the establishment and development of evergreen broadleaved forests facilitated the diversification of Collabieae.


Assuntos
Orchidaceae , Filogenia , Orchidaceae/genética , Orchidaceae/classificação , Florestas , Genomas de Plastídeos/genética , Filogeografia , DNA Espaçador Ribossômico/genética , Análise de Sequência de DNA , Ásia , DNA de Plantas/genética
2.
BMC Biol ; 21(1): 134, 2023 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-37280593

RESUMO

BACKGROUND: Sapria himalayana (Rafflesiaceae) is an endoparasitic plant characterized by a greatly reduced vegetative body and giant flowers; however, the mechanisms underlying its special lifestyle and greatly altered plant form remain unknown. To illustrate the evolution and adaptation of S. himalayasna, we report its de novo assembled genome and key insights into the molecular basis of its floral development, flowering time, fatty acid biosynthesis, and defense responses. RESULTS: The genome of S. himalayana is ~ 1.92 Gb with 13,670 protein-coding genes, indicating remarkable gene loss (~ 54%), especially genes involved in photosynthesis, plant body, nutrients, and defense response. Genes specifying floral organ identity and controlling organ size were identified in S. himalayana and Rafflesia cantleyi, and showed analogous spatiotemporal expression patterns in both plant species. Although the plastid genome had been lost, plastids likely biosynthesize essential fatty acids and amino acids (aromatic amino acids and lysine). A set of credible and functional horizontal gene transfer (HGT) events (involving genes and mRNAs) were identified in the nuclear and mitochondrial genomes of S. himalayana, most of which were under purifying selection. Convergent HGTs in Cuscuta, Orobanchaceae, and S. himalayana were mainly expressed at the parasite-host interface. Together, these results suggest that HGTs act as a bridge between the parasite and host, assisting the parasite in acquiring nutrients from the host. CONCLUSIONS: Our results provide new insights into the flower development process and endoparasitic lifestyle of Rafflesiaceae plants. The amount of gene loss in S. himalayana is consistent with the degree of reduction in its body plan. HGT events are common among endoparasites and play an important role in their lifestyle adaptation.


Assuntos
Genoma Mitocondrial , Transferência Genética Horizontal , Plantas/genética , Flores/genética , Filogenia
3.
J Integr Plant Biol ; 65(11): 2421-2436, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37642157

RESUMO

Phosphorus is a major nutrient vital for plant growth and development, with a substantial amount of cellular phosphorus being used for the biosynthesis of membrane phospholipids. Here, we report that NON-SPECIFIC PHOSPHOLIPASE C4 (NPC4) in rapeseed (Brassica napus) releases phosphate from phospholipids to promote growth and seed yield, as plants with altered NPC4 levels showed significant changes in seed production under different phosphate conditions. Clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated nuclease 9 (Cas9)-mediated knockout of BnaNPC4 led to elevated accumulation of phospholipids and decreased growth, whereas overexpression (OE) of BnaNPC4 resulted in lower phospholipid contents and increased plant growth and seed production. We demonstrate that BnaNPC4 hydrolyzes phosphosphingolipids and phosphoglycerolipids in vitro, and plants with altered BnaNPC4 function displayed changes in their sphingolipid and glycerolipid contents in roots, with a greater change in glycerolipids than sphingolipids in leaves, particularly under phosphate deficiency conditions. In addition, BnaNPC4-OE plants led to the upregulation of genes involved in lipid metabolism, phosphate release, and phosphate transport and an increase in free inorganic phosphate in leaves. These results indicate that BnaNPC4 hydrolyzes phosphosphingolipids and phosphoglycerolipids in rapeseed to enhance phosphate release from membrane phospholipids and promote growth and seed production.


Assuntos
Brassica napus , Fosfolipídeos , Esfingolipídeos , Fosfolipases Tipo C , Brassica napus/crescimento & desenvolvimento , Fosfolipases Tipo C/metabolismo , Esfingolipídeos/metabolismo , Fosfolipídeos/metabolismo , Sistemas CRISPR-Cas , Proteínas de Plantas/metabolismo , Sementes/crescimento & desenvolvimento , Técnicas de Inativação de Genes
4.
BMC Plant Biol ; 22(1): 448, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36123622

RESUMO

BACKGROUND: Plastomes of heterotrophic plants have been greatly altered in structure and gene content, owing to the relaxation of selection on photosynthesis-related genes. The orchid tribe Gastrodieae is the largest and probably the oldest mycoheterotrophic clade of the extant family Orchidaceae. To characterize plastome evolution across members of this key important mycoheterotrophic lineage, we sequenced and analyzed the plastomes of eleven Gastrodieae members, including representative species of two genera, as well as members of the sister group Nervilieae. RESULTS: The plastomes of Gastrodieae members contain 20 protein-coding, four rRNA and five tRNA genes. Evolutionary analysis indicated that all rrn genes were transferred laterally and together, forming an rrn block in the plastomes of Gastrodieae. The plastome GC content of Gastrodia species ranged from 23.10% (G. flexistyla) to 25.79% (G. javanica). The plastome of Didymoplexis pallens contains two copies each of ycf1 and ycf2. The synonymous and nonsynonymous substitution rates were very high in the plastomes of Gastrodieae among mycoheterotrophic species in Orchidaceae and varied between genes. CONCLUSIONS: The plastomes of Gastrodieae are greatly reduced and characterized by low GC content, rrn block formation, lineage-specific reconfiguration and gene content, which might be positively selected. Overall, the plastomes of Gastrodieae not only serve as an excellent model for illustrating the evolution of plastomes but also provide new insights into plastome evolution in parasitic plants.


Assuntos
Genomas de Plastídeos , Orchidaceae , Processos Heterotróficos/genética , Orchidaceae/genética , Fotossíntese/genética
5.
BMC Plant Biol ; 22(1): 179, 2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35392808

RESUMO

BACKGROUND: To illustrate the molecular mechanism of mycoheterotrophic interactions between orchids and fungi, we assembled chromosome-level reference genome of Gastrodia menghaiensis (Orchidaceae) and analyzed the genomes of two species of Gastrodia. RESULTS: Our analyses indicated that the genomes of Gastrodia are globally diminished in comparison to autotrophic orchids, even compared to Cuscuta (a plant parasite). Genes involved in arbuscular mycorrhizae colonization were found in genomes of Gastrodia, and many of the genes involved biological interaction between Gatrodia and symbiotic microbionts are more numerous than in photosynthetic orchids. The highly expressed genes for fatty acid and ammonium root transporters suggest that fungi receive material from orchids, although most raw materials flow from the fungi. Many nuclear genes (e.g. biosynthesis of aromatic amino acid L-tryptophan) supporting plastid functions are expanded compared to photosynthetic orchids, an indication of the importance of plastids even in totally mycoheterotrophic species. CONCLUSION: Gastrodia menghaiensis has the smallest proteome thus far among angiosperms. Many of the genes involved biological interaction between Gatrodia and symbiotic microbionts are more numerous than in photosynthetic orchids.


Assuntos
Gastrodia , Micorrizas , Orchidaceae , Gastrodia/genética , Micorrizas/genética , Orchidaceae/genética , Orchidaceae/microbiologia , Filogenia , Simbiose/genética
6.
Int J Mol Sci ; 23(15)2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35955715

RESUMO

Root foraging enables plants to obtain more soil nutrients in a constantly changing nutrient environment. Little is known about the adaptation mechanism of adventitious roots of plants dominated by asexual reproduction (such as tea plants) to soil potassium heterogeneity. We investigated root foraging strategies for K by two tea plants (low-K tolerant genotype "1511" and low-K intolerant genotype "1601") using a multi-layer split-root system. Root exudates, root architecture and transcriptional responses to K heterogeneity were analyzed by HPLC, WinRHIZO and RNA-seq. With the higher leaf K concentrations and K biological utilization indexes, "1511" acclimated to K heterogeneity better than "1601". For "1511", maximum total root length and fine root length proportion appeared on the K-enriched side; the solubilization of soil K reached the maximum on the low-K side, which was consistent with the amount of organic acids released through root exudation. The cellulose decomposition genes that were abundant on the K-enriched side may have promoted root proliferation for "1511". This did not happen in "1601". The low-K tolerant tea genotype "1511" was better at acclimating to K heterogeneity, which was due to a smart root foraging strategy: more roots (especially fine roots) were developed in the K-enriched side; more organic acids were secreted in the low-K side to activate soil K and the root proliferation in the K-enriched side might be due to cellulose decomposition. The present research provides a practical basis for a better understanding of the adaptation strategies of clonal woody plants to soil nutrient availability.


Assuntos
Camellia sinensis , Solo , Camellia sinensis/genética , Celulose , Raízes de Plantas/fisiologia , Potássio , Chá
7.
J Sci Food Agric ; 102(4): 1405-1414, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34374435

RESUMO

BACKGROUND: Tea plants have high nitrogen (N) consumptions, whereas molecular and physiological responses of tea plants to N recovery are still unclear. RESULTS: By using non-invasive micro-test technology (NMT), 15 N tracer technique, ultra-performance liquid chromatography (UPLC), and transcriptome sequencing technology, we investigated the N recovery-induced changes in N absorptions, N tissue distributions, contents of free amino acids (FAAs), and global transcription of the low-N tolerant and intolerant tea genotypes [i.e. Wuniuzao (W) and Longjing43 (L)]. The results showed that the phenotype of Wuniuzao was better than that of Longjing43 under low-N condition. The N absorption and utilization of Wuniuzao were superior to Longjing43 under N recovery. The γ-aminobutyric acid (GABA) ratio (N recovery/N deficiency) in the root of Wuniuzao was significantly higher than that of Longjing43, while the glutamic acid ratio in the root of Wuniuzao was significantly lower than that of Longjing43. This findings suggested that Wuniuzao tended to enhance the GABA synthesis, while Longjing43 tended to inhibit the GABA synthesis under N recovery. The key genes in response to N recovery in Wuniuzao included N transport (AMT and NRT), N transformation (NR, NirA, and GAD), and amino acid transport (GAT) genes. In addition, some ribosome and flavonoid biosynthesis genes might help to maintain proteome homeostasis. CONCLUSION: The N absorption and transport, and the conversion abilities of key amino acids (Glu and GABA) might improve the adaptability of tea plants to N recovery, which provided a basis for the breeding of N efficient tea varieties. © 2021 Society of Chemical Industry.


Assuntos
Camellia sinensis , Nitrogênio , Aminoácidos/metabolismo , Camellia sinensis/metabolismo , Regulação da Expressão Gênica de Plantas , Ácido Glutâmico/metabolismo , Nitrogênio/metabolismo , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo
8.
Mol Phylogenet Evol ; 157: 107062, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33387648

RESUMO

We explore the origins of the extraordinary plant diversity in the Qinghai-Tibetan Plateau (QTP) using Orchidinae (Orchidaceae) as a model. Our results indicate that six major clades in Orchidinae exhibited substantial variation in the temporal and spatial sequence of diversification. Our time-calibrated phylogenetic model suggests that the species-richness of Orchidinae arose through a combination of in situ diversification, colonisation, and local recruitment. There are multiple origins of species-richness of Orchidinae in the QTP, and pre-adaptations in clades from North Temperate and alpine regions were crucial for in situ diversification. The geographic analysis identified 29 dispersals from Asia, Africa and Europe into the QTP and 15 dispersals out. Most endemic species of Orchidinae evolved within the past six million years.


Assuntos
Adaptação Fisiológica , Ecossistema , Orchidaceae/classificação , Filogenia , Aclimatação , África , Ásia , Biodiversidade , Europa (Continente) , Tibet , Fatores de Tempo
9.
New Phytol ; 226(4): 1055-1073, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32176333

RESUMO

Plant oils are valuable commodities for food, feed, renewable industrial feedstocks and biofuels. To increase vegetable oil production, here we show that the nonspecific phospholipase C6 (NPC6) promotes seed oil production in the Brassicaceae seed oil species Arabidopsis, Camelina and oilseed rape. Overexpression of NPC6 increased seed oil content, seed weight and oil yield both in Arabidopsis and Camelina, whereas knockout of NPC6 decreased seed oil content and seed size. NPC6 is associated with the chloroplasts and microsomal membranes, and hydrolyzes phosphatidylcholine and galactolipids to produce diacylglycerol. Knockout and overexpression of NPC6 decreased and increased, respectively, the flux of fatty acids from phospholipids and galactolipids into triacylglycerol production. Candidate-gene association study in oilseed rape indicates that only BnNPC6.C01 of the four homeologues NPC6s is associated with seed oil content and yield. Haplotypic analysis indicates that the BnNPC6.C01 favorable haplotype can increase both seed oil content and seed yield. These results indicate that NPC6 promotes membrane glycerolipid turnover to accumulate TAG production in oil seeds and that NPC6 has a great application potential for oil yield improvement.


Assuntos
Brassicaceae , Brassicaceae/genética , Ácidos Graxos , Fosfolipases , Óleos de Plantas , Plantas Geneticamente Modificadas , Sementes
10.
Mol Phylogenet Evol ; 139: 106540, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31252068

RESUMO

To advance our knowledge of orchid relationships and timing of their relative divergence, we used 76 protein-coding genes from plastomes (ptCDS) and 38 protein-coding genes from mitochondrial genomes (mtCDS) of 74 orchids representing the five subfamilies and 18 tribes of Orchidaceae, to reconstruct the phylogeny and temporal evolution of the Orchidaceae. In our results, the backbone of orchid tree well supported with both datasets, but there are conflicts between these trees. The phylogenetic positions of two subfamilies (Vanilloideae and Cypripedioideae) are reversed in these two analyses. The phylogenetic positions of several tribes and subtribes, such as Epipogiinae, Gastrodieae, Nerviliinae, and Tropidieae, are well resolved in mtCDS tree. Thaieae have a different position among higher Epidendroideae, instead of sister to the higher Epidendroideae. Interrelationships of several recently radiated tribes within Epidendroideae, including Vandeae, Collabieae, Cymbidieae, Epidendreae, Podochileae, and Vandeae, have good support in the ptCDS tree, but most are not resolved in the mtCDS tree. Conflicts between the two datasets may be attributed to the different substitution rates in these two genomes and heterogeneity of substitution rate of plastome. Molecular dating indicated that the first three subfamilies, Apostasioideae, Cypripedioideae and Vanilloideae, diverged relatively quickly, and then there was a longer period before the last two subfamilies, Orchidoideae and Epidendroideae, began to radiate. Most mycoheterotrophic clades of Orchidaceae evolved in the last 30 million years with the exception of Gastrodieae.


Assuntos
Genoma Mitocondrial , Genomas de Plastídeos , Orchidaceae/classificação , Evolução Molecular , Orchidaceae/genética , Filogenia
11.
BMC Plant Biol ; 17(1): 222, 2017 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-29178835

RESUMO

BACKGROUND: Subtribe Orchidinae (Orchidaceae, Orchidoideae) are a nearly cosmopolitan taxon of terrestrial orchids, comprising about 1800 species in 47 to 60 genera. Although much progress has been made in recent years of phylogenetics of Orchidinae, considerable problems remain to be addressed. Based on molecular phylogenetics, we attempt to illustrate the phylogenetic relationships and discuss generic delimitation within Orchidinae. Seven DNA markers (five plastid and two nuclear), a broad sampling of Orchidinae (400 species in 52 genera) and three methods of phylogenetic analysis (maximum likelihood, maximum parsimony and Bayesian inference) were used. RESULTS: Orchidinae s.l. are monophyletic. Satyrium is sister to the rest of Orchidinae s.l. Brachycorythis and Schizochilus are successive sister to Asian-European Orchidinae s.s. Sirindhornia and Shizhenia are successive sister to clade formed by Tsaiorchis-Hemipilia-Ponerorchis alliance. Stenoglottis is sister to the Habenaria-Herminium-Peristylus alliance. Habenaria, currently the largest genus in Orchidinae, is polyphyletic and split into two distant clades: one Asian-Australian and the other African-American-Asian. Diplomeris is sister to Herminium s.l. plus Asian-Australian Habenaria. CONCLUSIONS: We propose to recognize five genera in the Ponerorchis alliance: Hemipilia, Ponerorchis s.l., Sirindhornia, Shizhenia and Tsaiorchis. Splitting Habenaria into two genera based on morphological characters and geographical distribution may be the least disruptive approach, and it is reasonable to keep Satyrium in Orchidinae.


Assuntos
Orchidaceae/classificação , DNA de Plantas , Marcadores Genéticos , Orchidaceae/genética , Filogenia
12.
Cladistics ; 32(2): 198-210, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34736301

RESUMO

The first comprehensive phylogenetic study of the orchid genus Herminium and its allies is presented, based on seven molecular markers (nuclear internal transcribed spacer, Xdh, chloroplast matK, psaB, psbA-trnH, rbcL and trnL-F) and 37 morphological characters. Phylogenetic analyses indicate that Herminium as currently delimited is paraphyletic and that several genera are deeply nested within it. Based on parsimony analysis of total evidence, the generic circumscription of Herminium is expanded to include Androcorys, Bhutanthera, Frigidorchis and Porolabium. Apomorphic and plesiomorphic character states are identified for various clades recovered in this study. A few species currently wrongly assigned to Peristylus and Platanthera are here included in Herminium. All necessary new combinations are made.

13.
Anal Bioanal Chem ; 408(22): 6071-8, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27370686

RESUMO

We screened a highly specific monoclonal antibody (McAb), named 6D, against Acidovorax avenae subsp. citrulli (Aac). Single McAb 6D was used as both nanogold-labeled antibody and test antibody to develop a single self-paired colloidal gold immunochromatographic test strip (Sa-GICS). The detection limit achieved using the Sa-GICS approach was 10(5) CFU/mL, with a result that can be observed by the naked eye within 10 min. Moreover, Sa-GICS can detect eight strains of Aac and display no cross-reactions with other pathogenic plant microorganisms. Artificial contamination experiments demonstrated that Sa-GICS would not be affected by impurities in the leaves or stems of the plants and were consistent with the PCR results. This is the first report on the development of a colloidal gold immunoassay strip with self-paired single McAb for the rapid detection of Aac. Graphical Abstract Schematic representation of the test strip.


Assuntos
Anticorpos Monoclonais/química , Cromatografia de Afinidade/métodos , Comamonadaceae/isolamento & purificação , Cucurbita/microbiologia , Doenças das Plantas/microbiologia , Fitas Reagentes/análise , Cromatografia de Afinidade/instrumentação , Desenho de Equipamento , Coloide de Ouro/química , Limite de Detecção
14.
Analyst ; 140(19): 6595-601, 2015 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-26300105

RESUMO

Being high throughput, rapid, automated, economical, convenient to operate and highly sensitive, protein arrays have been widely used in the analysis of tumor markers and veterinary drug residues. Pathogenic microbes also can be detected qualitatively by DNA array or protein array; however, their high throughput detection and quantification remains a big obstacle. To evaluate the potentiality of protein arrays for multiple quantitative detection of microorganisms with naked eye examination without the help of any equipment, here we developed a visual-antibody-macroarray (VAMA) aiming at rapid and simultaneous quantification of Escherichia coli O157:H7 and Shigella boydii. The results show that this VAMA is highly specific and is able to distinguish mixed Escherichia coli O157:H7 and Shigella boydii synchronously. The detection limits are equivalent to 3.4 × 10(5) CFU mL(-1) and 3.2 × 10(5) CFU mL(-1), respectively, which conform to the results of plate counting and ELISA. Importantly, the examination can be solely performed with the naked eye. Therefore, we provide an easy, reliable and rapid method for quantitative analysis of microorganisms.


Assuntos
Anticorpos Monoclonais/imunologia , Escherichia coli O157/isolamento & purificação , Análise Serial de Proteínas/métodos , Shigella boydii/isolamento & purificação , Colódio/química , Escherichia coli O157/imunologia , Limite de Detecção , Membranas Artificiais , Shigella boydii/imunologia , Fatores de Tempo
15.
Mol Phylogenet Evol ; 77: 41-53, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24747003

RESUMO

The subtribe Orchidinae, distributed predominantly in Eastern Asia and the Mediterranean, presents some of the most intricate taxonomic problems in the family Orchidaceae with respect to generic delimitation. Based on three DNA markers (plastid matK, rbcL, and nuclear ITS), morphological characters, and a broad sampling of Orchidinae and selected Habenariinae mainly from Asia (a total of 153 accessions of 145 species in 31 genera), generic delimitation and phylogenetic relationships within the subtribe Orchidinae and Habenariinae from Asia were assessed. Orchidinae and Asian Habenariinae are monophyletic, and Orchidinae is divided into distinct superclades. Many genera, such as Amitostigma, Habenaria, Hemipilia, Herminium, Platanthera, Peristylus and Ponerorchis, are not monophyletic. Habenaria is subdivided into two distantly related groups, while Platanthera is subdivided into three even more disparate groups. Many previously undetected phylogenetic relationships, such as clades formed by the Amitostigma-Neottianthe-Ponerorchis complex, Platanthera latilabris group, Ponerorchis chrysea, Sirindhornia, and Tsaiorchis, are well supported by both molecular and morphological evidence. We propose to combine Hemipiliopsis with Hemipilia, Amitostigma and Neottianthe with Ponerorchis, Smithorchis with Platanthera, and Aceratorchis and Neolindleya with Galearis, and to establish a new genus to accommodate Ponerorchis chrysea. Tsaiorchis and Sirindhornia are two distinctive genera supported by both molecular data and morphological characters. A new genus, Hsenhsua, and 41 new combinations are proposed based on these findings.


Assuntos
Orchidaceae/genética , Filogenia , Plastídeos/genética , Núcleo Celular/genética , Marcadores Genéticos , Orchidaceae/anatomia & histologia , Orchidaceae/classificação , Proteínas de Plantas/genética
16.
ScientificWorldJournal ; 2014: 857641, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24558339

RESUMO

Chinese hickory (Carya cathayensis), a popular nut food tree species, is mainly distributed in southeastern China. A field study was carried out to investigate the effect of long-term intensive management on fertility of soils under a C. cathayensis forest. Results showed that after 26 years' intensive management, the soil organic carbon (SOC) content of the A and B horizons reduced by 19% and 14%, respectively. The reduced components of SOC are mainly the alkyl C and O-alkyl C, whereas the aromatic C and carbonyl C remain unchanged. The reduction of active organic matter could result in degradation of soil fertility. The pH value of soil in the A horizon had dropped by 0.7 units on average. The concentrations of the major nutrients also showed a decreasing trend. On average the concentrations of total nitrogen (N), phosphorus (P), and potassium (K) of tested soils dropped by 21.8%, 7.6%, and 13.6%, respectively, in the A horizon. To sustain the soil fertility and C. cathayensis production, it is recommended that more organic fertilizers (manures) should be used together with chemical fertilizers. Lime should also be applied to reduce soil acidity.


Assuntos
Carbono/química , Carya , Fertilizantes , Solo/química , Nitrogênio/química , Fósforo/química , Potássio/química
17.
Med Phys ; 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38830128

RESUMO

BACKGROUND: Cone-beam computed tomography (CBCT), an important medical modality for disease detection and diagnosis, is currently widely used in clinical practice. However, due to the inconsistent response of CBCT detectors, the lack of proper calibration often leads to the occurrence of ring artifacts in CBCT-reconstructed images. These artifacts may affect physicians' assessment and diagnosis. Therefore, effective elimination of ring artifacts in CBCT images without degrading image quality is important. PURPOSE: Given the pros and cons of existing methods for removing ring artifacts in CBCT images, this paper is devoted to designing a specific Transformer for this task, leveraging the global and local modeling ability of Transformer. METHODS: We design a loss function with dual-domain information fusion for the vanilla Transformer to correct ring artifacts in CBCT images. The method operates in image domain to predict artifact-free outputs and preserve more image details. Meanwhile, we design a tailored loss function incorporating polar domain optimization to remove ring artifacts more effectively. Specifically, an unidirectional gradient loss that constrains vertical gradients in polar domain is imposed, based on the geometric prior that in polar coordinates, ring artifacts predominately affect horizontal gradients while minimally influencing vertical gradients. RESULTS: We conduct extensive ablative and comparative experiments on CBCT/CT image set to validate the performance of the proposed method. First, four ablation experiments demonstrate the feasibility of our approach. Then, we compare our method with several classical methods and the latest state-of-the-arts, and our method achieves the highest quality of corrected images as well as the best evaluation metrics. In these experiments, 5332 CT images were used for training, and 550 CT images, and 500 real CBCT images were used for testing. The source code is available at https://github.com/shasha521/CBCT. CONCLUSIONS: Experimental results demonstrate that our method can significantly improve the effectiveness of ring artifact correction. By capitalizing on dual-domain information fusion and a customized loss function, the improved Transformer can not only effectively remove ring artifacts in CBCT images, but also preserve the details of original images quite well.

18.
Mol Plant ; 17(2): 342-358, 2024 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-38243594

RESUMO

Lipid phosphorylation by diacylglycerol kinase (DGK) that produces phosphatidic acid (PA) plays important roles in various biological processes, including stress responses, but the underlying mechanisms remain elusive. Here, we show that DGK5 and its lipid product PA suppress ABA biosynthesis by interacting with ABA-DEFICIENT 2 (ABA2), a key ABA biosynthesis enzyme, to negatively modulate plant response to abiotic stress tested in Arabidopsis thaliana. Loss of DGK5 function rendered plants less damaged, whereas overexpression (OE) of DGK5 enhanced plant damage to water and salt stress. The dgk5 mutant plants exhibited decreased total cellular and nuclear levels of PA with increased levels of diacylglycerol, whereas DGK5-OE plants displayed the opposite effect. Interestingly, we found that both DGK5 and PA bind to the ABA-synthesizing enzyme ABA2 and suppress its enzymatic activity. Consistently, the dgk5 mutant plants exhibited increased levels of ABA, while DGK5-OE plants showed reduced ABA levels. In addition, we showed that both DGK5 and ABA2 are detected in and outside the nuclei, and loss of DGK5 function decreased the nuclear association of ABA2. We found that both DGK5 activity and PA promote nuclear association of ABA2. Taken together, these results indicate that both DGK5 and PA interact with ABA2 to inhibit its enzymatic activity and promote its nuclear sequestration, thereby suppressing ABA production in response to abiotic stress. Our study reveals a sophisticated mechanism by which DGK5 and PA regulate plant stress responses.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/metabolismo , Diacilglicerol Quinase/metabolismo , Ácido Abscísico/metabolismo , Fosforilação , Arabidopsis/metabolismo , Lipídeos , Regulação da Expressão Gênica de Plantas
19.
Prog Lipid Res ; 93: 101267, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38154743

RESUMO

Membrane lipidomes are dynamic and their changes generate lipid mediators affecting various biological processes. Phosphatidic acid (PA) has emerged as an important class of lipid mediators involved in a wide range of cellular and physiological responses in plants, animals, and microbes. The regulatory functions of PA have been studied primarily outside the nuclei, but an increasing number of recent studies indicates that some of the PA effects result from its action in nuclei. PA levels in nuclei are dynamic in response to stimuli. Changes in nuclear PA levels can result from activities of enzymes associated with nuclei and/or from movements of PA generated extranuclearly. PA has also been found to interact with proteins involved in nuclear functions, such as transcription factors and proteins undergoing nuclear translocation in response to stimuli. The nuclear action of PA affects various aspects of plant growth, development, and response to stress and environmental changes.


Assuntos
Ácidos Fosfatídicos , Transdução de Sinais , Animais , Ácidos Fosfatídicos/metabolismo , Transdução de Sinais/fisiologia , Plantas/metabolismo
20.
Heliyon ; 10(5): e26618, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38455539

RESUMO

Background: Coinfection poses a persistent threat to global public health due to its severe effect on individual-level infection risk and disease outcome. Coinfection of SARS-CoV2 with one or more pathogens has been documented. Nevertheless, this virus co-infected with the Hantaan virus (HTNV) is rarely reported. Case summary: Here, we presented three cases of HTNV complicated with SARS-CoV2 infection. Not only the conditions including general clinical manifestations, immune and inflammation parameters fluctuation presented in the single infection of HTNV or SARS-CoV2 can be found, but also the unexpected manifestations have attracted our attention that presented as more symptoms of HTNV infection including exudative changes in both lungs and an amount of bilateral pleural effusion as well as bilateral kidney enlargement rather than typical viral pneumonia in SARS-CoV2 infection. Fortunately, the conditions of patients gradually return to normal which is beneficial from the antiviral treatment, hemodialysis, and various supportive therapies including anti-inflammation, liver and gastric mucosa protection. Conclusion: Unexpected manifestations of coinfection patients present herein may be associated with multiple factors including virus load, competition or antagonism among antigens, and the susceptibility of target cells to the various pathogens, even though the pathogenesis of HTNV and SARS-CoV2 remains to be elucidated. Given that these two viruses have posed a profound influence on the socioeconomic, healthcare system worldwide, and the threat of coinfection to public health, it is warranted for clinicians, public health authorities, and infectious disease researchers to have a high index of consideration for patients co-infected with HTNV and SARS-CoV2.

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