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1.
Cell ; 163(1): 55-67, 2015 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-26406371

RESUMO

Radial glia, the neural stem cells of the neocortex, are located in two niches: the ventricular zone and outer subventricular zone. Although outer subventricular zone radial glia may generate the majority of human cortical neurons, their molecular features remain elusive. By analyzing gene expression across single cells, we find that outer radial glia preferentially express genes related to extracellular matrix formation, migration, and stemness, including TNC, PTPRZ1, FAM107A, HOPX, and LIFR. Using dynamic imaging, immunostaining, and clonal analysis, we relate these molecular features to distinctive behaviors of outer radial glia, demonstrate the necessity of STAT3 signaling for their cell cycle progression, and establish their extensive proliferative potential. These results suggest that outer radial glia directly support the subventricular niche through local production of growth factors, potentiation of growth factor signals by extracellular matrix proteins, and activation of self-renewal pathways, thereby enabling the developmental and evolutionary expansion of the human neocortex.


Assuntos
Neocórtex/citologia , Neocórtex/crescimento & desenvolvimento , Animais , Ciclo Celular , Humanos , Macaca , Camundongos , Neocórtex/metabolismo , Células-Tronco Neurais/metabolismo , Neurogênese , Neuroglia/citologia , Neuroglia/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Análise de Célula Única , Nicho de Células-Tronco
2.
Development ; 149(24)2022 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-36440598

RESUMO

Spatiotemporal regulation of the mechanistic target of rapamycin (mTOR) pathway is pivotal for establishment of brain architecture. Dysregulation of mTOR signaling is associated with a variety of neurodevelopmental disorders. Here, we demonstrate that the UBE4B-KLHL22 E3 ubiquitin ligase cascade regulates mTOR activity in neurodevelopment. In a mouse model with UBE4B conditionally deleted in the nervous system, animals display severe growth defects, spontaneous seizures and premature death. Loss of UBE4B in the brains of mutant mice results in depletion of neural precursor cells and impairment of neurogenesis. Mechanistically, UBE4B polyubiquitylates and degrades KLHL22, an E3 ligase previously shown to degrade the GATOR1 component DEPDC5. Deletion of UBE4B causes upregulation of KLHL22 and hyperactivation of mTOR, leading to defective proliferation and differentiation of neural precursor cells. Suppression of KLHL22 expression reverses the elevated activity of mTOR caused by acute local deletion of UBE4B. Prenatal treatment with the mTOR inhibitor rapamycin rescues neurogenesis defects in Ube4b mutant mice. Taken together, these findings demonstrate that UBE4B and KLHL22 are essential for maintenance and differentiation of the precursor pool through fine-tuning of mTOR activity.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Encéfalo , Células-Tronco Neurais , Serina-Treonina Quinases TOR , Ubiquitina-Proteína Ligases , Animais , Camundongos , Encéfalo/crescimento & desenvolvimento , Células-Tronco Neurais/metabolismo , Sirolimo , Serina-Treonina Quinases TOR/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo
3.
Chem Soc Rev ; 53(11): 5394-5427, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38597213

RESUMO

Advances in surface-enhanced Raman scattering (SERS) detection have helped to overcome the limitations of traditional in vitro diagnostic methods, such as fluorescence and chemiluminescence, owing to its high sensitivity and multiplex detection capability. However, for the implementation of SERS detection technology in disease diagnosis, a SERS-based assay platform capable of analyzing clinical samples is essential. Moreover, infectious diseases like COVID-19 require the development of point-of-care (POC) diagnostic technologies that can rapidly and accurately determine infection status. As an effective assay platform, SERS-based bioassays utilize SERS nanotags labeled with protein or DNA receptors on Au or Ag nanoparticles, serving as highly sensitive optical probes. Additionally, a microdevice is necessary as an interface between the target biomolecules and SERS nanotags. This review aims to introduce various microdevices developed for SERS detection, available for POC diagnostics, including LFA strips, microfluidic chips, and microarray chips. Furthermore, the article presents research findings reported in the last 20 years for the SERS-based bioassay of various diseases, such as cancer, cardiovascular diseases, and infectious diseases. Finally, the prospects of SERS bioassays are discussed concerning the integration of SERS-based microdevices and portable Raman readers into POC systems, along with the utilization of artificial intelligence technology.


Assuntos
Técnicas Biossensoriais , COVID-19 , Análise Espectral Raman , Humanos , COVID-19/diagnóstico , COVID-19/virologia , Nanopartículas Metálicas/química , SARS-CoV-2/isolamento & purificação , Sistemas Automatizados de Assistência Junto ao Leito , Ouro/química
4.
Nano Lett ; 24(11): 3307-3314, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38456631

RESUMO

Resulting from the dense packing of subnanometer molecular clusters, molecular granular materials (MGMs) are shown to maintain high elasticity far above their apparent glass transition temperature (Tg*). However, our microscopic understanding of their structure-property relationship is still poor. Herein, 1 nm polyhedral oligomeric silsesquioxanes (POSSs) are appended to a backbone chain in a brush configuration with different flexible linker chains. Assemblies of these brush polymers exhibit hierarchical relaxation dynamics with the glass transition arising from the cooperative dynamics of packed POSSs. The interaction among the assemblies can be strengthened by increasing the rigidity of linkers with the MGM relaxation modes changing from colloid- to polymer chain-like behavior, rendering their tunable viscoelasticity. This finally contributes to the decoupling of mechanical and thermal properties by showing elasticity dominant mechanical properties at a temperature 150 K above the Tg*.

5.
Small ; : e2400605, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38794874

RESUMO

The developments of mixed matrix membranes (MMMs) are severely hindered by the complex inter-phase interaction and the resulting poor utilization of inorganics' microporosity. Herein, a dual porosity framework is constructed in MMMs to enhance the accessibility of inorganics' microporosity to external gas molecules for the effective application of microporosity for gas separation. Nanocomposite organogels are first prepared from the supramolecular complexation of rigid polymers and 2 nm microporous coordination nanocages (CNCs). The network structures can be maintained with microporous features after solvent removal originated from the rigid nature of polymers, and the strong coordination and hydrogen bond between the two components. Moreover, the strong supramolecular attraction reinforces the frustrated packing of the rigid polymers on CNC surface, leading to polymer networks' extrinsic pores and the interconnection of CNCs' micro-cavities for the fast gas transportation. The gas permeabilities of the MMMs are 869 times for H2 and 1099 times for CO2 higher than those of pure polymers. The open metal sites from nanocage also contribute to the enhanced gas selectivity and the overall performance surpasses 2008 H2/CO2 Robeson upper bound. The supramolecular complexation reinforced packing frustration strategy offers a simple and practical solution to achieve improved gas permselectivity in MMMs.

6.
Inorg Chem ; 63(23): 10809-10816, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38813764

RESUMO

Electrochemically converting carbon dioxide (CO2) into valuable fuels and renewable chemical feedstocks is considered a highly promising approach to achieve carbon neutrality. In this work, a robust interfacial built-in electric field (BEF) has been successfully designed and created in Bi/Bi2Te3 nanowires (NWs). The Bi/Bi2Te3 NWs consistently maintain over 90% Faradaic efficiency (FE) within a wide potential range (-0.8 to -1.2 V), with HCOOH selectivity reaching 97.2% at -1.0 V. Moreover, the FEHCOOH of Bi/Bi2Te3 NWs can still reach 94.3% at a current density of 100 mA cm-2 when it is used as a cathode electrocatalyst in a flow-cell system. Detailed in situ experiments confirm that the presence of interfacial BEF between Bi and Bi/Bi2Te3 promotes the formation of *OHCO intermediates, thus facilitating the production of HCOOH species. DFT calculations show that Bi/Bi2Te3 NWs increase the formation energies of H* and *COOH while reducing the energy barrier for *OCHO formation, thus achieving a bidirectional optimization of intermediate adsorption. This work provides a feasible scheme for exploring electrocatalytic reaction intermediates by using the BEF strategy.

7.
Environ Toxicol ; 39(2): 952-964, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37975621

RESUMO

Di(2-ethylhexyl) phthalate (DEHP), an environmental endocrine disruptor, is one of the most common plasticizers and is widely used in various plastic products. DEHP induces apoptosis and oxidative stress and has been shown to have androgenic toxicity. However, the methods to combat DEHP-induced testicular damage and the mechanisms involved remain to be elucidated. In the present study, we used melatonin, which has strong antioxidant properties, to intervene in prepubertal mice and mouse Leydig cells (TM3) treated with DEHP or its metabolite mono(2-ethylhexyl) phthalate (MEHP). The results showed that melatonin protected against DEHP-induced testicular damage in prepubertal mice, mainly by protecting against DEHP-induced structural destruction of the germinal tubules and by attenuating the DEHP-induced decrease in testicular organ coefficients and testosterone levels. Transcriptomic analysis found that melatonin may attenuate DEHP-induced oxidative stress and apoptosis in prepubertal testes. In vitro studies further revealed that MEHP induces oxidative stress injury and increases apoptosis in TM3 cells, while melatonin reversed this damage. In vitro studies also found that MEHP exposure inhibited the expression levels of molecules related to the PI3K/AKT signaling pathway, and melatonin reversed this change. In conclusion, these findings suggest that melatonin protects against DEHP-induced prepubertal testicular injury via the PI3K/AKT signaling pathway, and provide a theoretical basis and experimental rationale for combating male reproductive dysfunction.


Assuntos
Dietilexilftalato , Melatonina , Masculino , Camundongos , Animais , Testículo , Melatonina/farmacologia , Dietilexilftalato/toxicidade , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Estresse Oxidativo , Apoptose
8.
Sensors (Basel) ; 24(8)2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38676151

RESUMO

The absence of some forms of non-verbal communication in virtual reality (VR) can make VR-based group discussions difficult even when a leader is assigned to each group to facilitate discussions. In this paper, we discuss if the sensor data from off-the-shelf VR devices can be used to detect opportunities for facilitating engaging discussions and support leaders in VR-based group discussions. To this end, we focus on the detection of suppressed speaking intention in VR-based group discussions by using personalized and general models. Our extensive analysis of experimental data reveals some factors that should be considered to enable effective feedback to leaders. In particular, our results show the benefits of combining the sensor data from leaders and low-engagement participants, and the usefulness of specific HMD sensor features.

9.
Sensors (Basel) ; 24(2)2024 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-38257455

RESUMO

While virtual reality (VR) technologies enable remote communication through the use of 3D avatars, it is often difficult to foster engaging group discussions without addressing the limitations to the non-verbal communication among distributed participants. In this paper, we discuss a technique to detect the intentions to speak in group discussions by tapping into intricate sensor data streams from VR headsets and hand-controllers. To this end, we developed a prototype VR group discussion app equipped with comprehensive sensor data-logging functions and conducted an experiment of VR group discussions (N = 24). We used the quantitative and qualitative experimental data to analyze participants' experiences of group discussions in relation to the temporal patterns of their different speaking intentions. We then propose a sensor-based mechanism for detecting speaking intentions by employing a sampling strategy that considers the temporal patterns of speaking intentions, and we verify the feasibility of our approach in group discussion settings.

10.
Angew Chem Int Ed Engl ; : e202408849, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38993071

RESUMO

The practical application of electrochemical CO2 reduction reaction (CO2RR) is hindered by the competing CO production, hydrogen evolution reaction (HER), and the lack of pH-universal catalysts. Here, Te-modified Bi nanorods (Te-Bi NRs) were synthesized through in situ reconstruction of Bi2Te4O11 NRs under the CO2RR condition. Our study illustrates that the complex reconstruction process of Bi2Te4O11 NRs during CO2RR could be decoupled into three distinct steps, i.e., the destruction of Bi2Te4O11, the formation of Te/Bi phases, and the dissolution of Te. The thus-obtained Te-Bi NRs exhibit remarkably high performance in CO2RR towards formate production, showing high activity, selectivity, and stability across all pH conditions (acidic, neutral, and alkaline). In a flow cell reactor under neutral, alkaline, or acidic conditions, the catalysts achieved HCOOH Faradaic efficiencies of up to 94.3%, 96.4%, and 91.0%, respectively, at a high current density of 300 mA cm-2. DFT calculations, along with operando spectral measurements, reveal that Te manipulates the Bi sites to an electron-deficient state, enhancing the adsorption strength of the *OCHO intermediate, and significantly suppressing the competing HER and CO production. This study highlights the substantial influence of catalyst reconstruction under operational conditions and offers insights into designing highly active and stable electrocatalysts towards CO2RR.

11.
Angew Chem Int Ed Engl ; 63(1): e202310953, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37749062

RESUMO

This Review addresses the use of X-ray and neutron scattering as well as X-ray absorption to describe how inorganic nanostructured materials assemble, evolve, and function in solution. We first provide an overview of techniques and instrumentation (both large user facilities and benchtop). We review recent studies of soluble inorganic nanostructure assembly, covering the disciplines of materials synthesis, processes in nature, nuclear materials, and the widely applicable fundamental processes of hydrophobic interactions and ion pairing. Reviewed studies cover size regimes and length scales ranging from sub-Ångström (coordination chemistry and ion pairing) to several nanometers (molecular clusters, i.e. polyoxometalates, polyoxocations, and metal-organic polyhedra), to the mesoscale (supramolecular assembly processes). Reviewed studies predominantly exploit 1) SAXS/WAXS/SANS (small- and wide-angle X-ray or neutron scattering), 2) PDF (pair-distribution function analysis of X-ray total scattering), and 3) XANES and EXAFS (X-ray absorption near-edge structure and extended X-ray absorption fine structure, respectively). While the scattering techniques provide structural information, X-ray absorption yields the oxidation state in addition to the local coordination. Our goal for this Review is to provide information and inspiration for the inorganic/materials science communities that may benefit from elucidating the role of solution speciation in natural and synthetic processes.

12.
Angew Chem Int Ed Engl ; 63(12): e202318355, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38265930

RESUMO

Cost-effective, non-fluorinated polymer proton exchange membranes (PEMs) are highly desirable in emerging hydrogen fuel cells (FCs) technology; however, their low proton conductivities and poor chemical and dimension stabilities hinder their further development as alternatives to commercial Nafion®. Here, we report the inorganic-organic hybridization strategy by facilely complexing commercial polymers, polyvinyl butyral (PVB), with inorganic molecular nanoparticles, H3 PW12 O40 (PW) via supramolecular interaction. The strong affinity among them endows the obtained nanocomposites amphiphilicity and further lead to phase separation for bi-continuous structures with both inter-connected proton transportation channels and robust polymer scaffold, enabling high proton conductivities, mechanical/dimension stability and barrier performance, and the H2 /O2 FCs equipped with the composite PEM show promising power densities and long-term stability. Interestingly, the hybrid PEM can be fabricated continuously in large scale at challenging ~10 µm thickness via typical tape casting technique originated from their facile complexing strategy and the hybrids' excellent mechanical properties. This work not only provides potential material systems for commercial PEMs, but also raises interest for the research on hybrid composites for PEMs.

13.
Biochem Biophys Res Commun ; 654: 62-72, 2023 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-36889036

RESUMO

Copper oxide nanoparticles (CuONPs) are metallic multifunctional nanoparticles with good conductive, catalytic and antibacterial characteristics that have shown to cause reproductive dysfunction. However, the toxic effect and potential mechanisms of prepubertal exposure to CuONPs on male testicular development have not been clarified. In this study, healthy male C57BL/6 mice received 0, 10, and 25 mg/kg/d CuONPs by oral gavage for 2 weeks (postnatal day 22-35). The testicular weight was decreased, testicular histology was disturbed and the number of Leydig cells was reduced in all CuONPs-exposure groups. Transcriptome profiling suggested steroidogenesis was impaired after exposure to CuONPs. The steroidogenesis-related genes mRNA expression level, concentration of serum steroids hormones and the HSD17B3-, STAR- and CYP11A1-positive Leydig cell numbers were dramatically reduced. In vitro, we exposed TM3 Leydig cells to CuONPs. Bioinformatic analysis, flow cytometry analysis and western blotting analysis confirmed that CuONPs can dramatically reduce Leydig cells viability, enhance apoptosis, trigger cell cycle arrest and reduce cell testosterone levels. U0126 (ERK1/2 inhibitor) significantly reversed TM3 Leydig cells injury and testosterone level decrease induced by CuONPs. These outcomes indicate that CuONPs exposure activates the ERK1/2 signaling pathway, which further promotes apoptosis and cell cycle arrest in TM3 Leydig cells, and ultimately leads to Leydig cells injury and steroidogenesis disorders.


Assuntos
Células Intersticiais do Testículo , Nanopartículas Metálicas , Camundongos , Animais , Masculino , Células Intersticiais do Testículo/metabolismo , Testículo/metabolismo , Testosterona/metabolismo , Cobre/metabolismo , Camundongos Endogâmicos C57BL , Nanopartículas Metálicas/toxicidade , Óxidos/farmacologia
14.
Anal Bioanal Chem ; 415(22): 5297-5309, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37439855

RESUMO

Invertase is the key enzyme involved in several crucial biological processes by hydrolyzing sucrose for production of glucose and fructose. Invertase plays important roles in the fields of food, pharmacy, cosmetics, biofuels, and agriculture. Detection of invertase activity is urgently necessary for scientific research and industrial processes. Herein, a continuous fluorometric method was developed for real-time detection of invertase activity. 8-Isoquinolinylboronic acid responded to fructose by formation of a fluorescent complex in turn-on manner, and served as a fluorescent sensor to selectively recognize fructose in ternary enzymatic mixture containing sucrose and glucose. The limit of detection (LOD) for fructose was 0.07 mM. Progress curve for fructose production was established by directly and continuously monitoring the fluorescence for invertase reaction with sucrose as substrate. Initial velocity was obtained to characterize invertase activity. LOD for invertase assay was 0.10 U·mL-1. Km and υmax for invertase were determined as 7.70 mM and 0.86 mM·min-1, respectively. Copper ion was demonstrated to inhibit the invertase activity with IC50 of 33.61 mM. Applicability in high-throughput screening for inhibitor was demonstrated. The proposed method allows for real-time, simple, and rapidly monitoring the invertase activity. It has a broad range of potential applications for kinetics and screening inhibitor.


Assuntos
Glucose , beta-Frutofuranosidase , beta-Frutofuranosidase/química , Frutose , Sacarose , Limite de Detecção
15.
Anal Bioanal Chem ; 415(24): 5939-5948, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37589939

RESUMO

The development of rapid and accurate assays is crucial to prevent the rapid spread of highly contagious respiratory infections such as coronavirus (COVID-19). Here, we developed a surface-enhanced Raman scattering (SERS)-enzyme-linked immunosorbent assay (ELISA) method that allows for the screening of multiple patient samples with high sensitivity on a 1536-well plate. As the well number on the ELISA well plate increases from 96 to 1536, the throughput of the assay increases but the sensitivity decreases due to the low number of biomarkers and the increase in non-specific binding species. To address this problem, silica (SiO2) beads were used to increase the surface-to-volume ratio and the loading density of biomarkers, thereby enhancing sensitivity. Using a three-dimensional gold nanoparticle (AuNP)@SiO2 SERS assay platform on a 1536-well plate, an immunoassay for the nucleocapsid protein biomarker of SARS-CoV-2 was performed and the limit of detection (LoD) decreased from 273 to 7.83 PFU/mL compared to using a two-dimensional assay platform with AuNPs. The proposed AuNPs@SiO2 SERS immunoassay (SERS-IA) platform is expected to dramatically decrease the false-negative diagnostic rate of the currently used lateral flow assay (LFA) or ELISA by enabling the positive diagnosis of patients with low virus concentrations.

16.
Macromol Rapid Commun ; 44(24): e2300477, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37814593

RESUMO

The emergence of polymers with intrinsic microporosity provides solutions for flexible gas separation membranes with both high gas permeability and selectivity. However, their applications are significantly hindered by the costly synthetic efforts, limited availability of chemical systems, and narrow window of microporosity sizes. Herein, flexible mixed matrix membranes with tunable intrinsic microporosity can be facilely fabricated from the coordination assembly of polymer brushes and coordination nanocages. Polymer brushes bearing isophthalic acid side groups can coordinate with Cu2+ to assemble into polymer networks crosslinked by 2 nm nanocages. The semi-flexible feature of the polymer brush and the high crosslinking density of the network prevent the network from collapsing during solvent removal and the obtained aerogels demonstrate hierarchical structure with dual porosity from the crosslinked polymer network and coordination nanocage, respectively. The porosity can be facilely tuned via the amount of Cu2+ by regulating the network crosslinking density and nanocage loadings, and finally, optimized gas separation that surpasses Robeson upper bound for H2 /CO2 can be achieved. The coordination-driven assembly protocol paves a new avenue for the cost-effective synthesis of polymers with intrinsic microporosity and the fabrication of flexible gas separation membranes.


Assuntos
Dióxido de Carbono , Polímeros , Polímeros/química , Dióxido de Carbono/química , Membranas Artificiais , Porosidade , Permeabilidade
17.
Proc Natl Acad Sci U S A ; 117(28): 16649-16659, 2020 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-32586957

RESUMO

Low availability of nitrogen (N) is often a major limiting factor to crop yield in most nutrient-poor soils. Arbuscular mycorrhizal (AM) fungi are beneficial symbionts of most land plants that enhance plant nutrient uptake, particularly of phosphate. A growing number of reports point to the substantially increased N accumulation in many mycorrhizal plants; however, the contribution of AM symbiosis to plant N nutrition and the mechanisms underlying the AM-mediated N acquisition are still in the early stages of being understood. Here, we report that inoculation with AM fungus Rhizophagus irregularis remarkably promoted rice (Oryza sativa) growth and N acquisition, and about 42% of the overall N acquired by rice roots could be delivered via the symbiotic route under N-NO3- supply condition. Mycorrhizal colonization strongly induced expression of the putative nitrate transporter gene OsNPF4.5 in rice roots, and its orthologs ZmNPF4.5 in Zea mays and SbNPF4.5 in Sorghum bicolor OsNPF4.5 is exclusively expressed in the cells containing arbuscules and displayed a low-affinity NO3- transport activity when expressed in Xenopus laevis oocytes. Moreover, knockout of OsNPF4.5 resulted in a 45% decrease in symbiotic N uptake and a significant reduction in arbuscule incidence when NO3- was supplied as an N source. Based on our results, we propose that the NPF4.5 plays a key role in mycorrhizal NO3- acquisition, a symbiotic N uptake route that might be highly conserved in gramineous species.


Assuntos
Proteínas de Transporte de Ânions/metabolismo , Glomeromycota/fisiologia , Micorrizas/fisiologia , Nitrogênio/metabolismo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Transporte de Ânions/genética , Regulação da Expressão Gênica de Plantas , Transportadores de Nitrato , Nitratos/metabolismo , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/microbiologia , Proteínas de Plantas/genética , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Sorghum/genética , Sorghum/metabolismo , Sorghum/microbiologia , Zea mays/genética , Zea mays/metabolismo , Zea mays/microbiologia
18.
Int J Mol Sci ; 24(4)2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36835208

RESUMO

Polygonatum cyrtonema Hua is a traditional Chinese herb propagated using rhizomes, and excessive demand for seedlings and quality deterioration caused by rhizome propagation has highlighted that seed propagation may be an ideal solution to address these issues. However, the molecular mechanisms involved in P. cyrtonema Hua seed germination and emergence stages are not well understood. Therefore, in the present study, we performed transcriptomics combined with hormone dynamics during different seed germination stages, and 54,178 unigenes with an average length of 1390.38 bp (N50 = 1847 bp) were generated. Significant transcriptomic changes were related to plant hormone signal transduction and the starch and carbohydrate pathways. Genes related to ABA(abscisic acid), IAA(Indole acetic acid), and JA(Jasmonic acid) signaling, were downregulated, whereas genes related to ethylene, BR(brassinolide), CTK(Cytokinin), and SA(salicylic acid) biosynthesis and signaling were activated during the germination process. Interestingly, GA biosynthesis- and signaling-related genes were induced during the germination stage but decreased in the emergence stage. In addition, seed germination significantly upregulated the expression of genes associated with starch and sucrose metabolism. Notably, raffinose biosynthesis-related genes were induced, especially during the emergence stage. In total, 1171 transcription factor (TF) genes were found to be differentially expressed. Our results provide new insights into the mechanisms underlying P. cyrtonema Hua seed germination and emergence processes and further research for molecular breeding.


Assuntos
Polygonatum , Transcriptoma , Germinação/genética , Polygonatum/genética , Sementes/metabolismo , Ácido Abscísico/metabolismo , Hormônios/metabolismo , Amido/metabolismo , Regulação da Expressão Gênica de Plantas
19.
Int J Mol Sci ; 24(16)2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37629123

RESUMO

Polygonatum cyrtonema (P. cyrtonema) is a valuable rhizome-propagating traditional Chinese medical herb. Polysaccharides (PCPs) are the major bioactive constituents in P. cyrtonema. However, the molecular basis of PCP biosynthesis in P. cyrtonema remains unknown. In this study, we measured the PCP contents of 11 wild P. cyrtonema germplasms. The results showed that PCP content was the highest in Lishui Qingyuan (LSQY, 11.84%) and the lowest in Hangzhou Lin'an (HZLA, 7.18%). We next analyzed the transcriptome profiles of LSQY and HZLA. Through a qRT-PCR analysis of five differential expression genes from the PCP biosynthesis pathway, phosphomannomutase, UDP-glucose 4-epimerase (galE), and GDP-mannose 4,6-dehydratase were determined as the key enzymes. A protein of a key gene, galE1, was localized in the chloroplast. The PCP content in the transiently overexpressed galE1 tobacco leaves was higher than in the wild type. Moreover, luciferase and Y1H assays indicated that PcWRKY31 and PcWRKY34 could activate galE1 by binding to its promoter. Our research uncovers the novel regulatory mechanism of PCP biosynthesis in P. cyrtonema and is critical to molecular-assisted breeding.


Assuntos
Polygonatum , Polygonatum/genética , Metabolismo dos Carboidratos , Perfilação da Expressão Gênica , Bioensaio , Cloroplastos
20.
Zhongguo Zhong Yao Za Zhi ; 48(7): 1840-1850, 2023 Apr.
Artigo em Zh | MEDLINE | ID: mdl-37282959

RESUMO

Uridine diphosphate glycosyltransferase(UGT) is a highly conserved protein in plants, which usually functions in secondary metabolic pathways. This study used the Hidden Markov Model(HMM) to screen out members of UGT gene family in the whole genome of Dendrobium officinale, and 44 UGT genes were identified. Bioinformatics was used to analyze the structure, phylogeny, and promoter region components of D. officinale genes. The results showed that UGT gene family could be divided into four subfamilies, and UGT gene structure was relatively conserved in each subfamily, with nine conserved domains. The upstream promoter region of UGT gene contained a variety of cis-acting elements related to plant hormones and environmental factors, indicating that UGT gene expression may be induced by plant hormones and external environmental factors. UGT gene expression in different tissues of D. officinale was compared, and UGT gene expression was found in all parts of D. officinale. It was speculated that UGT gene played an important role in many tissues of D. officinale. Through transcriptome analysis of D. officinale mycorrhizal symbiosis environment, low temperature stress, and phosphorus deficiency stress, this study found that only one gene was up-regulated in all three conditions. The results of this study can help understand the functions of UGT gene family in Orchidaceae plants and provide a basis for further study on the molecular regulation mechanism of polysaccharide metabolism pathway in D. officinale.


Assuntos
Dendrobium , Micorrizas , Dendrobium/genética , Reguladores de Crescimento de Plantas , Glicosiltransferases/genética , Glicosiltransferases/metabolismo , Perfilação da Expressão Gênica , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
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