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1.
Plant J ; 115(2): 452-469, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37026387

RESUMO

Plasma membrane represents a critical battleground between plants and attacking microbes. Necrosis-and-ethylene-inducing peptide 1 (Nep1)-like proteins (NLPs), cytolytic toxins produced by some bacterial, fungal and oomycete species, are able to target on lipid membranes by binding eudicot plant-specific sphingolipids (glycosylinositol phosphorylceramide) and form transient small pores, causing membrane leakage and subsequent cell death. NLP-producing phytopathogens are a big threat to agriculture worldwide. However, whether there are R proteins/enzymes that counteract the toxicity of NLPs in plants remains largely unknown. Here we show that cotton produces a peroxisome-localized enzyme lysophospholipase, GhLPL2. Upon Verticillium dahliae attack, GhLPL2 accumulates on the membrane and binds to V. dahliae secreted NLP, VdNLP1, to block its contribution to virulence. A higher level of lysophospholipase in cells is required to neutralize VdNLP1 toxicity and induce immunity-related genes expression, meanwhile maintaining normal growth of cotton plants, revealing the role of GhLPL2 protein in balancing resistance to V. dahliae and growth. Intriguingly, GhLPL2 silencing cotton plants also display high resistance to V. dahliae, but show severe dwarfing phenotype and developmental defects, suggesting GhLPL2 is an essential gene in cotton. GhLPL2 silencing results in lysophosphatidylinositol over-accumulation and decreased glycometabolism, leading to a lack of carbon sources required for plants and pathogens to survive. Furthermore, lysophospholipases from several other crops also interact with VdNLP1, implying that blocking NLP virulence by lysophospholipase may be a common strategy in plants. Our work demonstrates that overexpressing lysophospholipase encoding genes have great potential for breeding crops with high resistance against NLP-producing microbial pathogens.


Assuntos
Lisofosfolipase , Verticillium , Lisofosfolipase/genética , Gossypium/genética , Peroxissomos , Melhoramento Vegetal , Doenças das Plantas/microbiologia , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas
2.
Plant J ; 115(4): 910-925, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37133286

RESUMO

Mesocotyl length (ML) is a crucial factor in determining the establishment and yield of rice planted through dry direct seeding, a practice that is increasingly popular in rice production worldwide. ML is determined by the endogenous and external environments, and inherits as a complex trait. To date, only a few genes have been cloned, and the mechanisms underlying mesocotyl elongation remain largely unknown. Here, through a genome-wide association study using sequenced germplasm, we reveal that natural allelic variations in a mitochondrial transcription termination factor, OsML1, predominantly determined the natural variation of ML in rice. Natural variants in the coding regions of OsML1 resulted in five major haplotypes with a clear differentiation between subspecies and subpopulations in cultivated rice. The much-reduced genetic diversity of cultivated rice compared to the common wild rice suggested that OsML1 underwent selection during domestication. Transgenic experiments and molecular analysis demonstrated that OsML1 contributes to ML by influencing cell elongation primarily determined by H2 O2 homeostasis. Overexpression of OsML1 promoted mesocotyl elongation and thus improved the emergence rate under deep direct seeding. Taken together, our results suggested that OsML1 is a key positive regulator of ML, and is useful in developing varieties for deep direct seeding by conventional and transgenic approaches.


Assuntos
Oryza , Oryza/genética , Estudo de Associação Genômica Ampla , Sequência de Bases , Variação Genética
3.
Biochem Biophys Res Commun ; 706: 149766, 2024 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-38484568

RESUMO

Secretory myeloid-derived growth factor (MYDGF) exerts beneficial effects on organ repair, probably via a plasma membrane receptor; however, the identity of the expected receptor has remained elusive. In a recent study, MYDGF was reported as an agonist of the sphingosine-1-phosphate receptor 2 (S1PR2), an A-class G protein-coupled receptor that mediates the functions of the signaling lipid, sphingosine-1-phosphate (S1P). In the present study, we conducted living cell-based functional assays to test whether S1PR2 is a receptor for MYDGF. In the NanoLuc Binary Technology (NanoBiT)-based ß-arrestin recruitment assay and the cAMP-response element (CRE)-controlled NanoLuc reporter assay, S1P could efficiently activate human S1PR2 overexpressed in human embryonic kidney (HEK) 293T cells; however, recombinant human MYDGF, overexpressed either from Escherichia coli or HEK293 cells, had no detectable effect. Thus, the results demonstrated that human MYDGF is not a ligand of human S1PR2. Considering the high conservation of MYDGF and S1PR2 in evolution, MYDGF is also probably not a ligand of S1PR2 in other vertebrates.


Assuntos
Fator Estimulador de Colônias de Granulócitos , Receptores de Lisoesfingolipídeo , Esfingosina/análogos & derivados , Animais , Humanos , Receptores de Esfingosina-1-Fosfato , Receptores de Lisoesfingolipídeo/genética , Receptores de Lisoesfingolipídeo/metabolismo , Ligantes , Células HEK293 , Lisofosfolipídeos/farmacologia
4.
Nature ; 554(7690): 81-85, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29364873

RESUMO

Untethered small-scale (from several millimetres down to a few micrometres in all dimensions) robots that can non-invasively access confined, enclosed spaces may enable applications in microfactories such as the construction of tissue scaffolds by robotic assembly, in bioengineering such as single-cell manipulation and biosensing, and in healthcare such as targeted drug delivery and minimally invasive surgery. Existing small-scale robots, however, have very limited mobility because they are unable to negotiate obstacles and changes in texture or material in unstructured environments. Of these small-scale robots, soft robots have greater potential to realize high mobility via multimodal locomotion, because such machines have higher degrees of freedom than their rigid counterparts. Here we demonstrate magneto-elastic soft millimetre-scale robots that can swim inside and on the surface of liquids, climb liquid menisci, roll and walk on solid surfaces, jump over obstacles, and crawl within narrow tunnels. These robots can transit reversibly between different liquid and solid terrains, as well as switch between locomotive modes. They can additionally execute pick-and-place and cargo-release tasks. We also present theoretical models to explain how the robots move. Like the large-scale robots that can be used to study locomotion, these soft small-scale robots could be used to study soft-bodied locomotion produced by small organisms.


Assuntos
Biomimética/métodos , Desenho de Equipamento , Locomoção , Robótica/instrumentação , Elasticidade , Rotação , Natação , Caminhada
5.
J Environ Manage ; 359: 120782, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38669884

RESUMO

Capturing CO2 using clamshell/eggshell-derived CaO adsorbent can not only reduce carbon emissions but also alleviate the impact of trash on the environment. However, organic acid was usually used, high-temperature calcination was often performed, and CO2 was inevitably released during preparing CaO adsorbents from shell wastes. In this work, CaO-based CO2 adsorbent was greenly prepared by calcium-induced hydrogenation of clamshell and eggshell wastes in one pot at room/moderate temperature. CO2 adsorption experiments were performed in a thermogravimetric analyzer (TGA). The adsorption performance of the adsorbents obtained from the mechanochemical reaction (BM-C/E-CaO) was superior to that of the adsorbents obtained from the thermochemical reaction (Cal-C/E-CaO). The CO2 adsorption capacity of BM-C-CaO at 650 °C is up to 36.82 wt%, but the adsorption decay rate of the sample after 20 carbonation/calcination cycles is only 30.17%. This study offers an alternative energy-saving method for greenly preparing CaO-based adsorbent from shell wastes.


Assuntos
Dióxido de Carbono , Química Verde , Eliminação de Resíduos , Química Verde/métodos , Dióxido de Carbono/análise , Dióxido de Carbono/química , Hidrogenação , Temperatura , Exoesqueleto/química , Casca de Ovo/química , Eliminação de Resíduos/métodos , Adsorção
6.
Angew Chem Int Ed Engl ; 63(15): e202400012, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38340327

RESUMO

Hollow nanoporous carbon architectures (HNCs) present significant utilitarian value for a wide variety of applications. Facile and efficient preparation of HNCs has long been pursued but still remains challenging. Herein, we for the first time demonstrate that single-component metal-organic frameworks (MOFs) crystals, rather than the widely reported hybrid ones which necessitate tedious operations for preparation, could enable the facile and versatile syntheses of functional HNCs. By controlling the growth kinetics, the MOFs crystals (STU-1) are readily engineered into different shapes with designated styles of crystalline inhomogeneity. A subsequent one-step pyrolysis of these MOFs with intraparticle difference can induce a simultaneous self-hollowing and carbonization process, thereby producing various functional HNCs including yolk-shell polyhedrons, hollow microspheres, mesoporous architectures, and superstructures. Superior to the existing methods, this synthetic strategy relies only on the complex nature of single-component MOFs crystals without involving tedious operations like coating, etching, or ligand exchange, making it convenient, efficient, and easy to scale up. An ultra-stable Na-ion battery anode is demonstrated by the HNCs with extraordinary cyclability (93 % capacity retention over 8000 cycles), highlighting a high level of functionality of the HNCs.

7.
J Am Chem Soc ; 145(9): 5105-5113, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36795482

RESUMO

Covalent organic framework (COF) materials with porous character and robust structure have significant applied implications for K-ion battery (KIB) anodes, but they are limited by the low reversible capacity and inferior rate capability. Here, based on theoretical calculations, we identified that a porous bulk COF featuring numerous pyrazines and carbonyls in the π-conjugated periodic skeleton could provide multiple accessible redox-active sites for high-performance potassium storage. Its porous structure with a surface-dominated storage mechanism enabled the fast and stable storage of K-ions. Its insolubility in organic electrolytes and small volumetric change after potassiation ensured a robust electrode for stable cycling. As a KIB anode, this bulk COF demonstrated an unprecedentedly outstanding combination of reversible capacity (423 mAh g-1 at 0.1 C), rate capability (185 mAh g-1 at 10 C), and cyclability. The theoretical simulation and comprehensive characterizations confirmed the active sites are contributed by C═O, C═N, and the cation-π effect.

8.
Biochem Biophys Res Commun ; 679: 110-115, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37677979

RESUMO

The peptide hormone ghrelin (an agonist) and LEAP2 (an antagonist) play important functions in energy metabolism via their receptor GHSR, an A-class G protein-coupled receptor. Ghrelin, LEAP2, and GHSR are widely present from fishes to mammals. However, our recent study suggested that fish GHSRs have different binding properties to ghrelin: a GHSR from the lobe-finned fish Latimeria chalumnae (coelacanth) is efficiently activated by ghrelin, but GHSRs from the ray-finned fish Danio rerio (zebrafish) and Larimichthys crocea (large yellow croaker) have lost binding to ghrelin. Do fish GHSRs use another peptide as their agonist? In the present study we tested to two fish motilins from D. rerio and L. chalumnae because motilin is distantly related to ghrelin. In ligand binding and activation assays, the fish GHSRs from D. rerio and L. crocea displayed no detectable or very low binding to all tested motilins; however, the fish GHSR from L. chalumnae bound to its motilin with high affinity and was efficiently activated by it. Therefore, it seemed that motilin is not a ligand for GHSR in the ray-finned fish D. rerio and L. crocea, but is an efficient agonist for GHSR in the lobe-finned fish L. chalumnae, one of the closest fish relatives of tetrapods. The results of present study suggested that GHSR might have two efficient agonists, ghrelin and motilin, in ancient fishes; however, this feature might be only preserved in some extant fishes with ancient evolutionary origins.

9.
Amino Acids ; 55(11): 1557-1562, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37689599

RESUMO

Our recent study confirmed that the mature neuropeptide FAM237A, also known as neurosecretory protein GL (NPGL), is an efficient agonist for GPR83. The paralog FAM237B was previously reported as a weak agonist for GPR83. In the present study, we prepared mature human FAM237B via an intein-fusion approach and demonstrated that it could cause a significant activation effect at the nanomolar range (1‒10 nM) in a NanoBiT-based ß-arrestin recruitment assay. Thus, FAM237B appears to be another endogenous agonist for GPR83 and future in vivo studies will be required to confirm this.


Assuntos
Neuropeptídeos , Receptores Acoplados a Proteínas G , Humanos , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo
10.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 54(1): 186-191, 2023 Jan.
Artigo em Zh | MEDLINE | ID: mdl-36647665

RESUMO

Objective: To investigate the diagnostic value of serum pepsinogen (PG) Ⅰ/PGⅡ combined with tumor markers for Helicobacter pylori ( Hp)-positive early-stage gastric cancer. Methods: A retrospective study was conducted with the clinical data of 109 patients with gastric cancer (the gastric cancer group), 115 patients with chronic atrophic gastritis (the benign group), 112 cases of low-grade intraepithelial neoplasia (the low grade group), 109 cases of high-grade intraepithelial neoplasia (the high grade group), and 104 healthy subjects who underwent the relevant screening tests as part of their general physical examination (the healthy group). All the subjects were admitted to or received care at our hospital between May 2018 and April 2021. The levels of serum PGⅠ, PGⅡ, carcinoembryonic antigen (CEA), carbohydrate antigen 199 (CA199), and carbohydrate antigen 724 (CA724), and Hp infection status were examined. The findings for these indicators were compared among the groups, and the differences in serum indicators in Hp-positive and Hp-negative patients were compared. The diagnostic value of serum PGⅠ/PGⅡ combined with tumor markers for Hp-positive early-stage gastric cancer was assessed with receiver operating characteristic (ROC) curve. Results: The serum levels of PGⅠ and PGⅠ/PGⅡ decreased in successive order in the healthy group, the benign group, the low grade group, the high grade group, and the gastric cancer group ( P<0.05). The serum levels of PGⅡ, CEA, CA199, and CA724 in the gastric cancer group, the high grade group, and the low grade group were all higher than those in the healthy group and the benign group ( P<0.05). The Hp-positive rates of the gastric cancer group, the high grade group, the low grade group and the benign group were higher than that of the healthy group ( P<0.01). The levels of serum PGⅠ, PGⅡ, CEA, CA199, and CA724 of the Hp-positive subjects of the healthy group, the benign group, the low grade group, the high grade group, and the gastric cancer group were higher than those of the Hp-negative subjects ( P<0.05), while their PGⅠ/PGⅡ levels were always lower than those of the Hp-negative persons ( P<0.05). The specificity and area under the curve ( AUC) of serum PGⅠ/PGⅡ, CEA, CA199, and CA724 in the combined diagnosis of Hp-positive early-stage gastric cancer were higher than those of each indicator used alone in diagnosis ( P<0.05). In the gastric cancer group, the proportion of patients with PGⅠ/PGⅡ>2.32 was lower in the Hp-positive patients than that in the Hp-negative patients ( P<0.05), while the proportions of patients with CEA>66.99 ng/mL, CA199>110.35 U/mL, and CA724>44.20 U/mL were higher in the Hp-positive patients than those in the Hp-negative patients ( P<0.05). Conclusion: Testing PGⅠ/PGⅡ in combination with CEA, CA199, and CA724 results in better diagnostic value for Hp-positive early-stage gastric cancer.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Humanos , Biomarcadores Tumorais , Pepsinogênio C , Antígeno Carcinoembrionário , Pepsinogênio A , Neoplasias Gástricas/complicações , Neoplasias Gástricas/diagnóstico , Estudos Retrospectivos , Carboidratos , Infecções por Helicobacter/complicações , Infecções por Helicobacter/diagnóstico
11.
Arch Biochem Biophys ; 704: 108872, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-33857472

RESUMO

The gastric peptide ghrelin has important functions in energy metabolism and cellular homeostasis by activating growth hormone secretagogue receptor type 1a (GHSR1a). The N-terminal residues of ghrelin orthologs from all vertebrates are quite conserved; however, in orthologs from Cavia porcellus and Phyllostomus discolor, Ser2 and Leu5 are replaced by a smaller Ala and a positively charged Arg, respectively. In the present study, we first demonstrated that the hydrophobic Leu5 is essential for the function of human ghrelin, because Ala replacement caused an approximately 100-fold decrease in activity. However, replacement of Leu5 by an Arg residue caused much less disruption; further replacement of Ser2 by Ala almost restored full activity, although the [S2A] mutation itself showed slight detriments, implying that the positively charged Arg5 in the [S2A,L5R] mutant might form alternative interactions with certain receptor residues to compensate for the loss of the essential Leu5. To identify the responsible receptor residues, we screened GHSR1a mutants in which all conserved negatively charged residues in the extracellular regions and all aromatic residues in the ligand-binding pocket were mutated separately. According to the decrease in selectivity of the mutant receptors towards [S2A,L5R]ghrelin, we deduced that the positively charged Arg5 of the ghrelin mutant primarily interacts with the essential aromatic Phe286 at the extracellular end of the sixth transmembrane domain of GHSR1a by forming cation-π and π-π interactions. The present study provided new insights into the binding mechanism of ghrelin with its receptor, and thus would facilitate the design of novel ligands for GHSR1a.


Assuntos
Grelina/química , Receptores de Grelina/química , Animais , Quirópteros , Grelina/genética , Grelina/metabolismo , Cobaias , Células HEK293 , Humanos , Ligação Proteica , Domínios Proteicos , Receptores de Grelina/genética , Receptores de Grelina/metabolismo
12.
Amino Acids ; 53(6): 939-949, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33966114

RESUMO

Recent studies have demonstrated that liver-expressed antimicrobial peptide 2 (LEAP2) antagonizes the ghrelin receptor GHSR1a in mammals. However, its antagonistic function in lower vertebrates has not yet been tested. LEAP2 orthologs have been identified from a variety of fish species; however, previous studies all focused on their antimicrobial activity. To test whether LEAP2 functions as a GHSR1a antagonist in the lowest vertebrates, we studied the antagonism of a fish LEAP2 from Latimeria chalumnae, an extant coelacanth that is one of the closest living fish relatives of tetrapods. Using binding assays, we demonstrated that the coelacanth LEAP2 and ghrelin bound to the coelacanth GHSR1a with IC50 values in the nanomolar range. Using activation assays, we demonstrated that the coelacanth ghrelin activated the coelacanth GHSR1a with an EC50 value in the nanomolar range, and this activation effect was efficiently antagonized by a nanomolar range of the coelacanth LEAP2. In addition, we also showed that the human LEAP2 and ghrelin were as effective as their coelacanth orthologs towards the coelacanth GHSR1a; however, the coelacanth peptides had moderately lower activity towards the human GHSR1a. Thus, LEAP2 serves as an endogenous antagonist of the ghrelin receptor GHSR1a in coelacanth and the ghrelin-LEAP2-GHSR1a system has evolved slowly since its emergence in ancient fish.


Assuntos
Peptídeos Catiônicos Antimicrobianos , Proteínas Sanguíneas , Evolução Molecular , Proteínas de Peixes , Peixes , Receptores de Grelina , Animais , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/metabolismo , Proteínas Sanguíneas/genética , Proteínas Sanguíneas/metabolismo , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Peixes/genética , Peixes/metabolismo , Células HEK293 , Humanos , Receptores de Grelina/antagonistas & inibidores , Receptores de Grelina/genética , Receptores de Grelina/metabolismo
13.
Biochem J ; 477(17): 3199-3217, 2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32803260

RESUMO

Liver-expressed antimicrobial peptide 2 (LEAP2) was recently identified as a competitive antagonist for the G protein-coupled receptor GHSR1a, the cognate receptor for the gastric peptide ghrelin. LEAP2 plays important functions in energy metabolism by tuning the ghrelin-GHSR1a system. However, the molecular mechanism by which LEAP2 binds to GHSR1a is largely unknown. In the present study, we first conducted alanine-scanning mutagenesis on the N-terminal fragment of human LEAP2 and demonstrated that the positively charged Arg6 and the aromatic Phe4 are essential for LEAP2 binding to GHSR1a. To identify the receptor residues interacting with the essential Arg6 and Phe4 of LEAP2, we conducted extensive site-directed mutagenesis on GHSR1a. After all conserved negatively charged residues in the extracellular regions of human GHSR1a were mutated, only mutation of Asp99 caused much more detriments to GHSR1a binding to LEAP2 than binding to ghrelin, suggesting that the absolutely conserved Asp99 of GHSR1a probably interacts with the essential Arg6 of LEAP2. After five conserved Phe residues in the predicted ligand-binding pocket of human GHSR1a were mutated, three of them were identified as important for GHSR1a binding to LEAP2. According to a structural model of GHSR1a, we deduced that the adjacent Phe279 and Phe312 might interact with the essential Phe4 of LEAP2, while Phe119 might interact with the aromatic Trp5 of LEAP2. The present study provided new insights into the interaction of LEAP2 with its receptor, and would facilitate the design of novel ligands for GHSR1a in future studies.


Assuntos
Peptídeos Catiônicos Antimicrobianos/química , Proteínas Sanguíneas/química , Receptores de Grelina/química , Substituição de Aminoácidos , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/metabolismo , Proteínas Sanguíneas/genética , Proteínas Sanguíneas/metabolismo , Células HEK293 , Humanos , Mutagênese Sítio-Dirigida , Mutação de Sentido Incorreto , Ligação Proteica , Domínios Proteicos , Receptores de Grelina/genética , Receptores de Grelina/metabolismo
14.
Sensors (Basel) ; 21(7)2021 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-33916484

RESUMO

A compensation method for nonlinear vibration of a silicon micro resonant sensor is proposed and evaluated to be effective through simulation and experimental analysis. Firstly, the parameter characterization model of the silicon micro resonant sensor is established, which presents significant nonlinearity because of the nonlinear vibration of the resonant beam. A verification circuit is devised to imitate the nonlinear behavior of the model by matching the simulation measurement error of the frequency offset produced by the circuit block with the theoretical counterparts obtained from the model. Secondly, the principle of measurement error compensation is studied, and the compensation method dealing with nonlinear characteristics of the resonant beam is proposed by introducing a compensation beam and corresponding differential operations. The measurement error, compensation rate, and measurement residual between the two scenarios that use single beam and double beams, respectively, are derived and are compared with their simulation and experimental counterparts. The results coincide with the predicted trend, which verifies the effectiveness of the compensation method.

15.
Angew Chem Int Ed Engl ; 60(46): 24467-24472, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34519413

RESUMO

Heteroaromatic-conjugated aromatic molecules have inspired numerous interests in rechargeable batteries like Li-ion batteries, but were limited by low conductivity and easy dissolution in electrolytes. Herein, we immobilize a nitrogen-rich aromatic molecule tricycloquinazoline (TQ) and CuO4 unit into a two-dimensional (2D) conductive metal-organic framework (MOF) to unlock their potential for Li+ storage. TQ was identified redox activity with Li+ for the first time. With a synergistic effect of TQ and CuO4 unit, the 2D conductive MOF, named Cu-HHTQ (HHTQ=2,3,7,8,12,13-hexahydroxytricycloquinazoline), can facilitate the Li+ /e- transport and ensure a resilient electrode, resulting in a high capacity of 657.6 mAh g-1 at 600 mA g-1 with extraordinary high-rate capability and impressive cyclability. Our findings highlight an efficient strategy of constructing electrode materials for energy storage with combining multiple redox-active moieties into conductive MOFs.

16.
Plant Biotechnol J ; 18(1): 222-238, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31207065

RESUMO

Suberin acts as stress-induced antipathogen barrier in the root cell wall. CYP86A1 encodes cytochrome P450 fatty acid ω-hydroxylase, which has been reported to be a key enzyme for suberin biosynthesis; however, its role in resistance to fungi and the mechanisms related to immune responses remain unknown. Here, we identified a disease resistance-related gene, GbCYP86A1-1, from Gossypium barbadense cv. Hai7124. There were three homologs of GbCYP86A1 in cotton, which are specifically expressed in roots and induced by Verticillium dahliae. Among them, GbCYP86A1-1 contributed the most significantly to resistance. Silencing of GbCYP86A1-1 in Hai7124 resulted in severely compromised resistance to V. dahliae, while heterologous overexpression of GbCYP86A1-1 in Arabidopsis improved tolerance. Tissue sections showed that the roots of GbCYP86A1-1 transgenic Arabidopsis had more suberin accumulation and significantly higher C16-C18 fatty acid content than control. Transcriptome analysis revealed that overexpression of GbCYP86A1-1 not only affected lipid biosynthesis in roots, but also activated the disease-resistant immune pathway; genes encoding the receptor-like kinases (RLKs), receptor-like proteins (RLPs), hormone-related transcription factors, and pathogenesis-related protein genes (PRs) were more highly expressed in the GbCYP86A1-1 transgenic line than control. Furthermore, we found that when comparing V. dahliae -inoculated and noninoculated plants, few differential genes related to disease immunity were detected in the GbCYP86A1-1 transgenic line; however, a large number of resistance genes were activated in the control. This study highlights the role of GbCYP86A1-1 in the defence against fungi and its underlying molecular immune mechanisms in this process.


Assuntos
Parede Celular , Resistência à Doença/genética , Gossypium/genética , Doenças das Plantas/genética , Imunidade Vegetal , Verticillium/patogenicidade , Regulação da Expressão Gênica de Plantas , Gossypium/imunologia , Gossypium/microbiologia , Doenças das Plantas/microbiologia , Proteínas de Plantas , Plantas Geneticamente Modificadas
17.
Cancer Cell Int ; 20(1): 553, 2020 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-33298041

RESUMO

BACKGROUND: Recent studies suggest that long noncoding RNAs (lncRNAs) play an important role in tumorigenesis. As a newly identified lncRNA, the role of XIST in colorectal cancer (CRC) has not been established. Here, we sought to characterize the role of XIST and its associated regulatory network in CRC cells. METHODS: Expression of XIST mRNA, miR-497-5p, and forkhead box k1 (FOXK1) in CRC cells and tissues were detected using quantitative real-time polymerase chain reaction (qRT-PCR). Proliferation and apoptosis of CRC cells were determined using the CCK-8 cell counting assay and flow cytometry. The rate of cell migration and invasion was determined using a transwell assay. The relationships between XIST, miR-497-5p, and FOXK1 were predicted and confirmed using a dual-luciferase reporter assay. Expression of FOXK1 protein was quantified by Western blot. RESULTS: XIST and FOXK1 expression were significantly upregulated in CRC tissues and cell lines, while miR-497-5p expression was downregulated. XIST knockdown significantly suppressed CRC cell proliferation, migration, and invasion. Silencing of XIST also reversed the downregulation of miR-497-5p and upregulation of FOXK1. Moreover, blocking XIST expression was shown to inhibit CRC tumor growth in vivo and the effects were antagonized by the loss of miR-497-5p. miR-497-5p was shown to act as a sponge of XIST and also targeted FOXK1 in CRC cells. CONCLUSIONS: XIST was shown to promote the malignancy of CRC cells by competitively binding to miR-497-5p, resulting in an increase in FOXK1 expression. These results suggest that targeting of XIST may represent a possible treatment for CRC.

18.
Amino Acids ; 51(4): 619-626, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30604098

RESUMO

The insulin superfamily is a group of homologous proteins that are further divided into the insulin family and relaxin family according to their distinct receptors. All insulin superfamily members contain three absolutely conserved disulfide linkages and a nonchiral Gly residue immediately following the first B-chain cysteine. The functionality of this conserved Gly residue in the insulin family has been studied by replacing it with natural L-amino acids or the corresponding unnatural D-amino acids. However, such analysis has not been conducted on relaxin family members. In the present study, we conducted chiral mutagenesis on the conserved B11Gly of the chimeric relaxin family peptide R3/I5, which is an efficient agonist for receptor RXFP3 and RXFP4. Similar to the effects on insulin family foldability, L-Ala or L-Ser substitution completely abolished the in vitro refolding of a recombinant R3/I5 precursor; whereas, D-Ala or D-Ser substitution had no detrimental effect on refolding of a semi-synthetic R3/I5 precursor, suggesting that the conserved Gly residue controls the foldability of relaxin family members. In contrast to the effect on insulin family activity, D-Ala or D-Ser replacement had no detrimental effect on the binding and activation potencies of the mature R3/I5 towards both RXFP3 and RXFP4, suggesting that the conserved Gly residue is irrelevant to the relaxin family's activity. The present study revealed functionality of the conserved B-chain Gly residue for a relaxin family peptide for the first time, providing an overview of its contribution to foldability and activity of the insulin superfamily.


Assuntos
Glicina/metabolismo , Insulina/metabolismo , Fragmentos de Peptídeos/metabolismo , Proteínas/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Peptídeos/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Relaxina/metabolismo , Glicina/química , Glicina/genética , Humanos , Insulina/química , Insulina/genética , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Ligação Proteica , Dobramento de Proteína , Proteínas/química , Proteínas/genética , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Relaxina/química , Relaxina/genética
19.
Pediatr Res ; 86(5): 595-602, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31261369

RESUMO

BACKGROUND: Decreased expression of the renal aquaporin (AQP) protein family is associated with hydronephrosis in adult humans and animals. However, the expression of AQPs, especially subtypes AQP1-3, which play a core role in the urinary concentration function, in hydronephrotic human fetuses is not clear. The aim of this study is to investigate the expression of the AQP1-3 in normal and hydronephrotic human fetal kidneys. METHODS: Twenty-one normal and six hydronephrotic kidney (HK) samples were harvested from abortive fetuses. Meanwhile, seven normal adult human kidney samples were collected as positive controls. Quantitative real-time PCR, western blotting, and immunohistochemistry were used to analyze the expression of AQP1-3. RESULTS: Both the protein and messenger mRNA expression levels of AQP1-3 increased with gestational age in the normal fetuses, but the levels were significantly lower than those in the adult tissues and significantly higher than those in the hydronephrotic fetuses at the same gestational age. CONCLUSIONS: The increased expression of AQP1-3 with gestational age in the fetal kidney may indicate maturation of the urinary concentrating ability. The lower expression of AQP1-3 in HKs may reflect a maturation obstacle with regard to urinary concentration in human hydronephrotic fetuses.


Assuntos
Aquaporina 1/metabolismo , Aquaporina 3/metabolismo , Feto/metabolismo , Hidronefrose/metabolismo , Rim/metabolismo , Aquaporina 1/genética , Aquaporina 3/genética , Estudos de Casos e Controles , Humanos , Rim/embriologia , RNA Mensageiro/genética
20.
Proc Natl Acad Sci U S A ; 113(41): E6007-E6015, 2016 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-27671658

RESUMO

Shape-programmable matter is a class of active materials whose geometry can be controlled to potentially achieve mechanical functionalities beyond those of traditional machines. Among these materials, magnetically actuated matter is particularly promising for achieving complex time-varying shapes at small scale (overall dimensions smaller than 1 cm). However, previous work can only program these materials for limited applications, as they rely solely on human intuition to approximate the required magnetization profile and actuating magnetic fields for their materials. Here, we propose a universal programming methodology that can automatically generate the required magnetization profile and actuating fields for soft matter to achieve new time-varying shapes. The universality of the proposed method can therefore inspire a vast number of miniature soft devices that are critical in robotics, smart engineering surfaces and materials, and biomedical devices. Our proposed method includes theoretical formulations, computational strategies, and fabrication procedures for programming magnetic soft matter. The presented theory and computational method are universal for programming 2D or 3D time-varying shapes, whereas the fabrication technique is generic only for creating planar beams. Based on the proposed programming method, we created a jellyfish-like robot, a spermatozoid-like undulating swimmer, and an artificial cilium that could mimic the complex beating patterns of its biological counterpart.

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