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1.
Chem Biodivers ; 19(3): e202100897, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35083849

RESUMO

A new lignan (4,4',5'-trihydroxy-5,3'-dimethoxy-3-O-9',2-(7'R)-lignan, 1) and eight C(6)-oxygenated flavonoids (2-9), including a newly identified flavonoid (7,3',4'-trihydroxy-3,5,6-trimethoxyflavone, 2), were isolated from the inflorescence of Ambrosia artemisiifolia L. The structures of these isolates were determined using extensive spectroscopic analyses and comparison with data previously reported in the literature. The absolute configuration of compound 1 was established using electronic circular dichroism (ECD) spectrum. All the flavonoids (2-9) showed inhibitory effects on LPS-induced NO production in RAW264.7 cells, with the inhibition rate ranging from 24.51 % to 69.82 % at 50 µM. The in vitro cytotoxicity study showed that compounds 3-8 have a 60 % inhibition rate against SMMC-7721 at a concentration of 40 µM, while compounds 5 and 8 also exhibited inhibitory activity against HL-60 at 40 µM with the inhibition rate of 83.36 % and 52.01 %, respectively.


Assuntos
Ambrosia , Lignanas , Ambrosia/química , Flavonoides/química , Flavonoides/farmacologia , Inflorescência , Lignanas/química , Lignanas/farmacologia , Estrutura Molecular
2.
Planta ; 252(1): 1, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32504137

RESUMO

MAIN CONCLUSION: Maize has a set of dark response genes, expression of which is influenced by multiple factor and varies with maize inbred lines but without germplasm specificity. The response to photoperiod is a common biological issue across the species kingdoms. Dark is as important as light in photoperiod. However, further in-depth understanding of responses of maize (Zea mays) to light and dark transition under photoperiod is hindered due to the lack of understanding of dark response genes. With multiple public "-omic" datasets of temperate and tropical/subtropical maize, 16 maize dark response genes, ZmDRGs, were found and had rhythmic expression under dark and light-dark cycle. ZmDRGs 6-8 were tandemly duplicated. ZmDRGs 2, 13, and 14 had a chromosomal collinearity with other maize genes. ZmDRGs 1-11 and 13-16 had copy-number variations. ZmDRGs 2, 9, and 16 showed 5'-end sequence deletion mutations. Some ZmDRGs had chromatin interactions and underwent DNA methylation and/or m6A mRNA methylation. Chromosomal histones associated with 15 ZmDRGs were methylated and acetylated. ZmDRGs 1, 2, 4, 9, and 13 involved photoperiodic phenotypes. ZmDRG16 was within flowering-related QTLs. ZmDRGs 1, 3, and 6-11 were present in cis-acting expression QTLs (eQTLs). ZmDRGs 1, 4, 6-9, 11, 12, and 14-16 showed co-expression with other maize genes. Some of ZmDRG-encoded ZmDRGs showed obvious differences in abundance and phosphorylation. CONCLUSION: Sixteen ZmDRGs 1-16 are associated with the dark response of maize. In the process of post-domestication and/or breeding, the ZmDRGs undergo the changes without germplasm specificity, including epigenetic modifications, gene copy numbers, chromatin interactions, and deletion mutations. In addition to effects by these factors, ZmDRG expression is influenced by promoter elements, cis-acting eQTLs, and co-expression networks.


Assuntos
Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo , Locos de Características Quantitativas/genética , Zea mays/genética , Ritmo Circadiano , Fotoperíodo , Proteínas de Plantas/genética , Zea mays/fisiologia , Zea mays/efeitos da radiação
3.
Mar Drugs ; 18(5)2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-32456085

RESUMO

A new pentaketide derivative, penilactonol A (1), and two new hydroxyphenylacetic acid derivatives, (2'R)-stachyline B (2) and (2'R)-westerdijkin A (3), together with five known metabolites, bisabolane-type sesquiterpenoids 4-6 and meroterpenoids 7 and 8, were isolated from the solid culture of a marine alga-associated fungus Penicillium chrysogenum LD-201810. Their structures were elucidated based on extensive spectroscopic analyses, including 1D/2D NMR and high resolution electrospray ionization mass spectra (HRESIMS). The absolute configurations of the stereogenic carbons in 1 were determined by the (Mo2(OAc)4)-induced circular dichroism (CD) and comparison of the calculated and experimental electronic circular dichroism (ECD) spectra, while the absolute configuration of the stereogenic carbon in 2 was established using single-crystal X-ray diffraction analysis. Compounds 2 and 3 adapt the 2'R-configuration as compared to known hydroxyphenylacetic acid-derived and O-prenylated natural products. The cytotoxicity of 1-8 against human carcinoma cell lines (A549, BT-549, HeLa, HepG2, MCF-7, and THP-1) was evaluated. Compound 3 exhibited cytotoxicity to the HepG2 cell line with an IC50 value of 22.0 µM. Furthermore, 5 showed considerable activities against A549 and THP-1 cell lines with IC50 values of 21.2 and 18.2 µM, respectively.


Assuntos
Antineoplásicos/farmacologia , Eutrofização , Células Hep G2/efeitos dos fármacos , Penicillium chrysogenum , Animais , Antineoplásicos/química , Humanos , Concentração Inibidora 50 , Relação Estrutura-Atividade
4.
Molecules ; 25(24)2020 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-33419270

RESUMO

Five new cyclic diarylheptanoids (platycary A-E, compounds 1-5) and three previously identified analogues (i.e., phttyearynol (compound 6), myricatomentogenin (compound 7), and juglanin D (compound 8)) were isolated from the stem bark of Platycarya strobilacea. The structures of these compounds were determined using NMR, HRESIMS, and electronic circular dichroism (ECD) data. The cytotoxicity of compounds 1-5 and their ability to inhibit nitric oxide (NO) production, as well as protect against the corticosterone-induced apoptosis of Pheochromocytoma (PC12) cells, were evaluated in vitro using the appropriate bioassays. Compounds 1 and 2 significantly inhibited the corticosterone-induced apoptosis of PC12 cells at a concentration of 20 µΜ.


Assuntos
Diarileptanoides/farmacologia , Juglandaceae/química , Estrutura Molecular , Neoplasias/tratamento farmacológico , Extratos Vegetais/farmacologia , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Diarileptanoides/isolamento & purificação , Humanos , Neoplasias/patologia , Óxido Nítrico/metabolismo , Ratos
5.
Planta ; 250(5): 1621-1635, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31399791

RESUMO

MAIN CONCLUSION: Cassava AGPase and AGPase genes have some unique characteristics. ADP-glucose pyrophosphorylase (AGPase) is a rate-limiting enzyme for starch synthesis. In this study, cassava AGPase genes (MeAGP) were analyzed based on six cultivars and one wild species. A total of seven MeAGPs was identified, including four encoding AGPase large subunits (MeAGPLs 1, 2, 3 and 4) and three encoding AGPase small subunits (MeAGPSs 1, 2 and 3). The copy number of MeAGPs varied in cassava germplasm materials. There were 14 introns for MeAGPLs 1, 2 and 3, 13 introns for MeAGPL4, and 8 introns for other three MeAGPSs. Multiple conservative amino acid sequence motifs were found in the MeAGPs. There were differences in amino acids at binding sites of substrates and regulators among different MeAGP subunits and between MeAGPs and a potato AGPase small subunit (1YP2:B). MeAGPs were all located in chloroplasts. MeAGP expression was not only associated with gene copy number and types/combinations, regions and levels of the DNA methylation but was also affected by environmental factors with the involvement of various transcription factors in multiple regulation networks and in various cis-elements in the gene promoter regions. The MeAGP activity also changed with environmental conditions and had potential differences among the subunits. Taken together, MeAGPs differ in number from those of Arabidopsis, potato, maize, banana, sweet potato, and tomato.


Assuntos
Variações do Número de Cópias de DNA , Genoma de Planta/genética , Glucose-1-Fosfato Adenililtransferase/genética , Manihot/enzimologia , Motivos de Aminoácidos , Sítios de Ligação , Cloroplastos/metabolismo , Evolução Molecular , Manihot/genética , Proteínas de Plantas/genética , Subunidades Proteicas , Especificidade da Espécie , Amido/metabolismo
6.
Yi Chuan ; 39(4): 302-312, 2017 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-28420609

RESUMO

Stomata are small adjustable pores on the surface (epidermis) of land plants that act as a main conduit for gas exchange. They not only play an essential role in photosynthesis of green plants but also exert an important influence on the global carbon and water cycle. There are great differences between monocots and dicots in distribution and morphological structure of the stomata, affecting the species-specific regulation of stomatal development. In this review, we summarize the molecular regulation networks associated with stomatal precursor cell fate determination and the epigenetic mechanisms on regulation of polar cell division. We also outline the stomatal development processes mediated by crosstalk between exogenous and intrinsic signals, and propose a model of multilevel regulation of stomatal development.


Assuntos
Estômatos de Plantas/metabolismo , Transporte Proteico/fisiologia , Transdução de Sinais/fisiologia
7.
Planta ; 242(6): 1391-403, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26253178

RESUMO

MAIN CONCLUSION: Effects of a low aluminum (Al) dose were characterized. The Al supplement inhibited root growth but enhanced leaf growth in maize lines with different Al sensitivities. High levels of Al are phytotoxic especially in acidic soils. The beneficial effects of low Al levels have been reported in some plant species, but not in maize. Maize is relatively more sensitive to Al toxicity than other cereals. Seedlings, at the three leaf stage, of four Chinese maize foundation parent inbred lines with different Al tolerances, were exposed to complete Hoagland's nutrient solution at pH 4.5 supplemented with 48 µM Al(3+) under controlled growth conditions, and then the Al stress (AS) was removed. The leaf and root growth, root cell viability, superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ions (K(+), Ca(++) and Mg(++)), photosynthetic rate and chlorophyll, protein and malondialdehyde contents in tissues were assayed. In conclusion, a low Al dose inhibits root growth but enhances leaf growth in maize. The Al-promoted leaf growth is likely a result of increased protein synthesis, a lowered Ca(++) level, and the discharge of the growth-inhibitory factors. The Al-promoted leaf growth may be a 'memory' effect caused by the earlier AS in maize. Al causes cell wall rupture, and a loss of K(+), Ca(++) and Mg(++) from root cells. CAT is an auxiliary antioxidant enzyme that works selectively with either SOD or POD against AS-related peroxidation, depending on the maize tissue. CAT is a major antioxidant enzyme responsible for root growth, but SOD is important for leaf growth during AS and after its removal. Our results contribute to understanding how low levels of Al affect maize and Al-resistant mechanisms in maize.


Assuntos
Alumínio/farmacologia , Folhas de Planta/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Zea mays/efeitos dos fármacos , Antioxidantes/metabolismo , Catalase/metabolismo , Malondialdeído/metabolismo , Micronutrientes/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Raízes de Plantas/crescimento & desenvolvimento , Superóxido Dismutase/metabolismo , Zea mays/crescimento & desenvolvimento
8.
Plant Cell Environ ; 38(8): 1479-89, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24910171

RESUMO

Response of maize to photoperiods affects adaption of this crop to environments. We characterize the phenotypes of four temperate-adapted maize foundation parents, Huangzao 4, Chang 7-2, Ye 478 and Zheng 58, and two tropically adapted maize foundation parents, M9 and Shuang M9 throughout the growth stage under three constant photoperiod regimes in a daily cycle of 24 h at 28 °C, and analysed expression of 48 photoperiod response-associated genes. Consequently, long photoperiod (LP) repressed development of the tassels of photoperiod-sensitive maize lines at V9 stage, and caused subsequent failure in flowering; failure of photoperiod-sensitive maize lines in flowering under LP was associated with lower expression of flowering-related genes; photoperiod changes could make a marked impact on spatial layout of maize inflorescence. The larger oscillation amplitude of expression of photoperiod-responsive genes occurred in LP-sensitive maize lines. In conclusion, failure in development of tassels at V9 stage under LP is an early indicator for judging photoperiod sensitivity. The adaptation of temperate-adapted maize lines to LP is due to the better coordination of expression among photoperiod-sensing genes instead of the loss of the genes. High photoperiod sensitivity of maize is due to high expression of circadian rhythm-responding genes improperly early in the light.


Assuntos
Fotoperíodo , Zea mays/fisiologia , Flores/genética , Flores/crescimento & desenvolvimento , Flores/fisiologia , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Inflorescência/anatomia & histologia , Fenótipo , Folhas de Planta/genética , Caules de Planta/anatomia & histologia , Zea mays/genética
9.
J Asian Nat Prod Res ; 16(2): 135-40, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24320876

RESUMO

A new intact resin glycoside (3) and two glycosidic acids (1 and 2), all having a common trisaccharide moiety and (11S)-hydroxytetradecanoic acid or (3S,11S)-dihydroxytetradecanoic acid as the aglycone, were obtained from the roots of Porana duclouxii. Their structures were elucidated by spectroscopic analyses and chemical correlations. These compounds represent the first examples of resin glycosides from the genus Porana.


Assuntos
Convolvulaceae/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Glicosídeos/isolamento & purificação , Resinas Vegetais/química , Medicamentos de Ervas Chinesas/química , Glicosídeos/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Raízes de Plantas/química
10.
Plant Sci ; 346: 112163, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38880339

RESUMO

A20/AN1 zinc-finger domain-containing genes are very promising candidates in improving plant tolerance to abiotic stresses, but considerably less is known about functions and mechanisms for many of them. In this study, Metip3 (5, and 7), cassava (Manihot esculenta) A20/AN1 genes carrying one A20 domain and one AN1 domain, were functionally characterized at different layers. Metip3 (5, and 7) proteins were all located in the nucleus. No interactions were found between these three proteins. Metip3 (5, and 7)-expressing Arabidopsis was more tolerant to multiple abiotic stresses by Na, Cd, Mn, Al, drought, high temperature, and low temperature. Metip3- and Metip5-expressing Arabidopsis was sensitive to Cu stress, while Metip7-expressing Arabidopsis was insensitive. The H2O2 production significantly decreased in all transgenic Arabidopsis, however, O2·- production significantly decreased in Metip3- and Metip5-expressing Arabidopsis but did not significantly changed in Metip7-expressing Arabidopsis under drought. Metip3 (5, and 7) expression-silenced cassava showed the decreased tolerance to drought and NaCl, presented significant decreases in superoxide dismutase and catalase activities and proline content, and displayed a significant increase in malondialdehyde content under drought. Taken together with transcriptome sequencing analysis, it is suggested that Metip5 gene can not only affect signal transduction related to plant hormone, mitogen activated protein kinases, and starch and sucrose metabolism, DRE-binding transcription factors, and antioxidants, conferring the drought tolerance, but also might deliver the signals from DREB2A INTERACTING PROTEIN1, E3 ubiquitin-protein ligases to proteasome, leading to the drought intolerance. The results are informative not only for further study on evolution of A20/AN1 genes but also for development of climate resilient crops.

11.
Plant Sci ; 327: 111543, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36427558

RESUMO

High air temperature (HAT) and natural soil drought (NSD) have seriously affected crop yield and frequently take place in a HAT-NSD combination. Maize (Zea mays) is an important crop, thermophilic but not heat tolerant. In this study, HAT, NSD, and HAT-NSD effects on maize inbred line Huangzao4 -were characterized. Main findings were as follows: H2O2 and O- accumulated much more in immature young leaves than in mature old leaves under the stresses. Lateral roots were highly distributed near the upper pot mix layers under HAT and near root tips under HAT-NSD. Saccharide accumulated mainly in stressed root caps (RC) and formed a highly accumulated saccharide band at the boundary between RC and meristematic zone. Lignin deposition was in stressed roots under NSD and HAT-NSD. Chloroplasts increased in number and formed a high-density ring around leaf vascular bundles (VB) under HAT and HAT-NSD, and sparsely scattered in the peripheral area of VBs under NSD. The RC cells containing starch granules were most under NAD-HAT but least under HAT. Under NSD and HAT-NSD followed by re-watering, anther number per tassel spikelet reduced to 3. These results provide multiple clues for further distinguishing molecular mechanisms for maize to tolerate these stresses.


Assuntos
Secas , Zea mays , Peróxido de Hidrogênio , Temperatura , Folhas de Planta , Solo
12.
Plant Physiol Biochem ; 194: 394-405, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36481708

RESUMO

The sugar transporter SWEET plays a role in plant growth, carbon allocation, and abiotic stress resistance. We examined the function of SWEET in cassava (Manihot esculenta Crantz) under water and salt stress. Bioinformatics, subcellular localization, yeast deficient complementation, and virus-induced gene silencing (VIGS) were used to examine the function of SWEET in cassava. Twenty-eight MeSWEETs genes were found based on the conserved domain MtN3/saliva of SWEET transporters, two MeSWEET15a/b of them were identified by phylogenetic analysis, which were located on the cell membrane. They transfer sucrose, fructose, glucose, and mannitol from culture media to yeast cells, predominately transferring sucrose via bleeding fluid saps in plant. Leaf sucrose content was increased in MeSWEET15a/b-silenced cassava plants, resulting in changes in carbon distribution, with an increase in starch accumulation in the leaves and a decrease in starch accumulation in the roots. The silencing of MeSWEET15a/b genes led to tolerance to water and salt stress, consistent with a high accumulation of osmolytes, and low lipid membrane peroxidation. Changes in sugar distribution increased the expression of MeTOR and MeE2Fa in pTRV2-MeSWEET15a and pTRV2-MeSWEET15b cassava leaves. MeSWEET15a/b acts as pivotal modulators of sugar distribution and tolerance to water and high salt stress in cassava.


Assuntos
Manihot , Água , Água/metabolismo , Açúcares/metabolismo , Manihot/genética , Manihot/metabolismo , Filogenia , Saccharomyces cerevisiae/metabolismo , Amido/metabolismo , Estresse Salino , Sacarose/metabolismo
13.
Sci Rep ; 13(1): 7375, 2023 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-37147346

RESUMO

The genes enconding proteins containing plasma membrane proteolipid 3 (PMP3) domain are responsive to abiotic stresses, but their functions in maize drought tolerance remain largely unknown. In this study, the transgenic maize lines overexpressing maize ZmPMP3g gene were featured by enhanced drought tolerance; increases in total root length, activities of superoxide dismutase and catalase, and leaf water content; and decreases in leaf water potential, levels of O2-·and H2O2, and malondialdehyde content under drought. Under treatments with foliar spraying with abscisic acid (ABA), drought tolerance of both transgenic line Y7-1 overexpressing ZmPMP3g and wild type Ye478 was enhanced, of which Y7-1 showed an increased endogenous ABA and decreased endogenous gibberellin (GA) 1 (significantly) and GA3 (very slightly but not significantly) and Ye478 had a relatively lower ABA and no changes in GA1 and GA3. ZmPMP3g overexpression in Y7-1 affected the expression of multiple key transcription factor genes in ABA-dependent and -independent drought signaling pathways. These results indicate that ZmPMP3g overexpression plays a role in maize drought tolerance by harmonizing ABA-GA1-GA3 homeostasis/balance, improving root growth, enhancing antioxidant capacity, maintaining membrane lipid integrity, and regulating intracellular osmotic pressure. A working model on ABA-GA-ZmPMP3g was proposed and discussed.


Assuntos
Resistência à Seca , Zea mays , Zea mays/genética , Zea mays/metabolismo , Peróxido de Hidrogênio/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Ácido Abscísico/metabolismo , Estresse Fisiológico , Secas , Água/metabolismo , Regulação da Expressão Gênica de Plantas
14.
AoB Plants ; 15(1): plac057, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36654987

RESUMO

The proteins with DNA-binding preference to the consensus DNA sequence (A/T) GATA (A/G) belong to a GATA transcription factor family, with a wide array of biological processes in plants. Cassava (Manihot esculenta) is an important food crop with high production of starch in storage roots. Little was however known about cassava GATA domain-containing genes (MeGATAs). Thirty-six MeGATAs, MeGATA1 to MeGATA36, were found in this study. Some MeGATAs showed a collinear relationship with orthologous genes of Arabidopsis, poplar and potato, rice, maize and sorghum. Eight MeGATA-encoded proteins (MeGATAs) analysed were all localized in the nucleus. Some MeGATAs had potentials of binding ligands and/or enzyme activity. One pair of tandem-duplicated MeGATA17-MeGATA18 and 30 pairs of whole genome-duplicated MeGATAs were found. Fourteen MeGATAs showed low or no expression in the tissues. Nine analysed MeGATAs showed expression responses to abiotic stresses and exogenous phytohormones. Three groups of MeGATA protein interactions were found. Fifty-three miRNAs which can target 18 MeGATAs were identified. Eight MeGATAs were found to target other 292 cassava genes, which were directed to radial pattern formation and phyllome development by gene ontology enrichment, and autophagy by Kyoto Encyclopaedia of Genes and Genomes enrichment. These data suggest that MeGATAs are functional generalists in interactions between cassava growth and development, abiotic stresses and starch metabolism.

15.
Plants (Basel) ; 12(5)2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36904053

RESUMO

Water level rise is considered an environmental filter for the growth and reproduction of aquatic plants in lakes. Some emergent macrophytes can form floating mats, enabling them to escape from the negative effects of deep water. However, an understanding of which species can be uprooted and form floating mats easily and what factors affect these tendencies remains greatly elusive. We conducted an experiment to determine whether the monodominance of Zizania latifolia in the emergent vegetation community in Lake Erhai was related to its floating mat formation ability and to try to find the reasons for its floating mat formation ability during the continuous increase in water level over the past few decades. Our results showed that both the frequency and biomass proportion of Z. latifolia were greater among the plants on the floating mats. Furthermore, Z. latifolia was more likely to be uprooted than the other three previously dominant emergent species due to its smaller angle between the plant and the horizontal plane, rather than the root:shoot or volume:mass ratios. The dominance of Z. latifolia in the emergent community in Lake Erhai is due to its easier ability to become uprooted, allowing it to outperform other emergent species and become the single dominant emergent species under the environmental filter of deep water. The ability to uproot and form floating mats may be a competitive survival strategy for emergent species under the conditions of continuous significant water level rise.

16.
Zhonghua Nan Ke Xue ; 18(2): 109-14, 2012 Feb.
Artigo em Zh | MEDLINE | ID: mdl-22568205

RESUMO

OBJECTIVE: To establish a high-sensitivity, high-specificity and low-cost hydrogel chip platform for the clinical screening of Y chromosome microdeletions. METHODS: Site-specific extended primers with a common sequence at the 5' end were used for hybridizing with the target. The Cy5-dUTP was incorporated into the products by primer extension, and the products were labeled with fluorescence. Then the extended products were added to the chip for hybridizing with acrylamide-modified common probes immobilized on the chip. After removal of the free Cy5-dUTP by electrophoresis, the signals were obtained by fluorescence scanning. And the detecting conditions of this method were optimized. RESULTS: SY254 of 9 samples was successfully detected with the hydrogel chip. The results showed that 3 were normal and the other 6 with microdeletions (1 female sample as a negative control), which coincided with the results of conventional multiplex PCR-electrophoresis. CONCLUSION: The hydrogel chip platform we established has provided a new technique for the detection of Y chromosome microdeletions, and is beneficial to the diagnosis and treatment of male infertility.


Assuntos
Análise de Sequência com Séries de Oligonucleotídeos/métodos , Transtornos do Cromossomo Sexual no Desenvolvimento Sexual/genética , Carbocianinas , Deleção Cromossômica , Cromossomos Humanos Y/genética , Nucleotídeos de Desoxiuracil , Humanos , Hidrogéis , Infertilidade Masculina , Masculino , Aberrações dos Cromossomos Sexuais , Transtornos do Cromossomo Sexual no Desenvolvimento Sexual/diagnóstico
17.
Chemosphere ; 286(Pt 1): 131591, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34303053

RESUMO

Drinking water safety cannot be overemphasized. Filamentous fungi have many excellent features for metal removal. Both graphene oxide (GO) and activated carbon (AC) are conventional metal adsorbents, but they are not suitable for large-scale use due to high cost. In this study, a low dosage of conidia (2.0 × 104 conidia/mL) of metal-resistant/adapted filamentous fungus Penicillium janthinillum strain GXCR were co-immobilized with a low dosage of 0.5 mg/L GO or 0.5 mg/L AC by embedding in 2% polyvinyl alcohol (PVA)-3% sodium alginate (SA), generating six types of microbead adsorbents (MBAs) to remove metals from a low concentration of either single metal (100 mg/L) or mixed metals (100 mg/L each) of Pb (II), Fe (III) and Cu (II) in drinking water. Fungus GXCR-containing MBAs had higher specific surface areas (SSAs), better mesoporous structures, and a higher removal rate (85-98.99%) of single or mixed metals. Singl-metal adsorptions of MBAs were almost unaffected by temperature changes. MBAs showed a stable removal rate of 87-94% during four cycles of adsorption-desorption of single metal. Single-metal adsorptions were well described by multiple models of Freundlich isotherm with constant values of 0.21-0.432, Langmuir isotherm with constant values of 0.037-0.17, Pseudo-fist-order, Pseudo-second-order, and intra-particle diffusion (IPD). In conclusion, co-immobilization between GXCR, GO and AC can make metal removal more efficient. Adsorption capacity is increased with SSAs but not in the same proportion. Single-metal adsorptions involve multiple mechanisms of monolayer and multilayer adsorptions, external mass transfer, and IPD. IPD is important but not the only one rate-controlling step for single-metal adsorptions.


Assuntos
Água Potável , Penicillium , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Compostos Férricos , Grafite , Cinética , Chumbo , Poluentes Químicos da Água/análise
18.
Sci Adv ; 8(36): eabq5108, 2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36083908

RESUMO

Nucleotide-binding, leucine-rich repeat receptors (NLRs) perceive pathogen effectors to trigger plant immunity. The direct recognition mechanism of pathogen effectors by coiled-coil NLRs (CNLs) remains unclear. We demonstrate that the Triticum monococcum CNL Sr35 directly recognizes the pathogen effector AvrSr35 from Puccinia graminis f. sp. tritici and report a cryo-electron microscopy structure of Sr35 resistosome and a crystal structure of AvrSr35. We show that AvrSr35 forms homodimers that are disassociated into monomers upon direct recognition by the leucine-rich repeat domain of Sr35, which induces Sr35 resistosome assembly and the subsequent immune response. The first 20 amino-terminal residues of Sr35 are indispensable for immune signaling but not for plasma membrane association. Our findings reveal the direct recognition and activation mechanism of a plant CNL and provide insights into biochemical function of Sr35 resistosome.

19.
Cell Res ; 32(12): 1068-1085, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36357786

RESUMO

The emerging SARS-CoV-2 variants, commonly with many mutations in S1 subunit of spike (S) protein are weakening the efficacy of the current vaccines and antibody therapeutics. This calls for the variant-proof SARS-CoV-2 vaccines targeting the more conserved regions in S protein. Here, we designed a recombinant subunit vaccine, HR121, targeting the conserved HR1 domain in S2 subunit of S protein. HR121 consisting of HR1-linker1-HR2-linker2-HR1, is conformationally and functionally analogous to the HR1 domain present in the fusion intermediate conformation of S2 subunit. Immunization with HR121 in rabbits and rhesus macaques elicited highly potent cross-neutralizing antibodies against SARS-CoV-2 and its variants, particularly Omicron sublineages. Vaccination with HR121 achieved near-full protections against prototype SARS-CoV-2 infection in hACE2 transgenic mice, Syrian golden hamsters and rhesus macaques, and effective protection against Omicron BA.2 infection in Syrian golden hamsters. This study demonstrates that HR121 is a promising candidate of variant-proof SARS-CoV-2 vaccine with a novel conserved target in the S2 subunit for application against current and future SARS-CoV-2 variants.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Animais , Cricetinae , Camundongos , Humanos , Coelhos , SARS-CoV-2 , Macaca mulatta , Mesocricetus , Glicoproteína da Espícula de Coronavírus/genética , COVID-19/prevenção & controle , Anticorpos Neutralizantes , Camundongos Transgênicos , Anticorpos Antivirais
20.
Theor Appl Genet ; 123(6): 943-58, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21735236

RESUMO

Changes in water potential, growth elongation, photosynthesis of three-leaf-old seedlings of maize inbred line YQ7-96 under water deficit (WD) for 0.5, 1 and 2 h and re-watering (RW) for 24 h were characterized. Gene expression was analyzed using cDNA microarray covering 11,855 maize unigenes. As for whole maize plant, the expression of WD-regulated genes was characterized by up-regulation. The expression of WD-regulated genes was categorized into eight different patterns, respectively, in leaves and roots. Newly found and WD-affected cellular processes were metabolic process, amino acid and derivative metabolic process and cell death. A great number of the analyzed genes were found to be regulated specifically by RW and commonly by both WD and RW, respectively, in leaves. It is therefore concluded that (1) whole maize plant tolerance to WD, as well as growth recovery from WD, depends at least in part on transcriptional coordination between leaves and roots; (2) WD exerts effects on the maize, especially on basal metabolism; (3) WD could probably affect CO(2) uptake and partitioning, and transport of fixed carbons; (4) WD could likely influence nuclear activity and genome stability; and (5) maize growth recovery from WD is likely involved in some specific signaling pathways related to RW-specific responsive genes.


Assuntos
Secas , Genes de Plantas , Água , Zea mays/crescimento & desenvolvimento , Zea mays/genética , Dióxido de Carbono/metabolismo , Elementos de DNA Transponíveis , Expressão Gênica , Regulação da Expressão Gênica de Plantas , Família Multigênica , Análise de Sequência com Séries de Oligonucleotídeos , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plântula/genética , Plântula/metabolismo , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Estresse Fisiológico , Zea mays/metabolismo
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