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1.
Biochem Biophys Res Commun ; 666: 162-169, 2023 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-37196606

RESUMO

We have identified a corazonin G protein-coupled receptor (GPCR) gene in the tick Ixodes scapularis, which likely plays a central role in the physiology and behavior of this ectoparasite. This receptor gene is unusually large (1.133 Mb) and yields two corazonin (CRZ) receptor splice variants, where nearly half of the coding regions are exchanged: CRZ-Ra (containing exon 2, exon 3, and exon 4 of the gene) and CRZ-Rb (containing exon 1, exon 3, and exon 4 of the gene). CRZ-Ra codes for a GPCR with a canonical DRF sequence at the border of the third transmembrane helix and the second intracellular loop. The positively-charged R residue from the DRF sequence is important for coupling of G proteins after activation of a GPCR. CRZ-Rb, in contrast, codes for a GPCR with an unusual DQL sequence at this position, still retaining a negatively-charged D residue, but lacking a positively-charged R residue, suggesting different G protein coupling. Another difference between the two splice variants is that exon 2 from CRZ-Ra codes for an N-terminal signal sequence. Normally, GPCRs do not have N-terminal signal sequences, although a few mammalian GPCRs have. In the tick CRZ-Ra, the signal sequence probably assists with inserting the receptor correctly into the RER membrane. We stably transfected Chinese Hamster Ovary cells with each of the two splice variants and carried out bioluminescence bioassays that also included the use of the human promiscuous G protein G16. CRZ-Ra turned out to be selective for I. scapularis corazonin (EC50 = 10-8 M) and could not be activated by related neuropeptides like adipokinetic hormone (AKH) and AKH/corazonin-related peptide (ACP). Similarly, also CRZ-Rb could only be activated by corazonin, although about 4-fold higher concentrations were needed to activate it (EC50 = 4 x 10-8 M). The genomic organization of the tick corazonin GPCR gene is similar to that of the insect AKH and ACP receptor genes. This similar genomic organization can also be found in the human gonadotropin-releasing hormone (GnRH) receptor gene, confirming previous conclusions that the corazonin, AKH, and ACP receptor genes are the true arthropod orthologues of the human GnRH receptor gene.


Assuntos
Ixodes , Neuropeptídeos , Animais , Cricetinae , Humanos , Ixodes/genética , Ixodes/metabolismo , Células CHO , Cricetulus , Neuropeptídeos/genética , Proteínas de Insetos/genética , Receptores Acoplados a Proteínas G/genética , Sinais Direcionadores de Proteínas
2.
Appl Microbiol Biotechnol ; 103(6): 2715-2729, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30673809

RESUMO

The thermotolerant Kluyveromyces marxianus is a potential candidate for high-temperature ethanol fermentation. Although K. marxianus exhibited high ethanol productivity at 45 °C during the early fermentation stage, we observed a fermentation arrest due to the accumulated inhibitors. The stress responses of K. marxianus during high-temperature fermentation were revealed based on integration of RNA sequencing (RNA-Seq) and metabolite data. High temperature stimulated mitochondrial respiration but repressed the tricarboxylic acid (TCA) cycle, leading to increased generation of reactive oxygen species (ROS) and a lowered ratio of reduced nicotinamide adenine dinucleotide (NADH)/oxidized nicotinamide adenine dinucleotide (NAD+). Glycerol production was enhanced during the early fermentation stage, which might contribute to NADH reoxidation and ROS generation. Excess ROS could be neutralized by reduced nicotinamide adenine dinucleotide phosphate (NADPH) that might be reserved in the following ways: (1) decreased biosynthesis of branched-chain amino acids (BCAAs) reduced NADPH consumption; (2) enhanced acetic acid production increased NADPH regeneration. The degree of fatty acid unsaturation was also reduced to adapt to high temperature. In addition, stress responses were also observed after the fermentation arrest at 45 °C. Genes related to peroxidase activity, iron-sulfur cluster assembly, and flavin mononucleotide (FMN) binding were downregulated, while genes associated with DNA repair and lipid composition of the plasma were upregulated. The yeast also produced more ergosterol to deal with ethanol stress. This study gains comprehensive insights into the K. marxianus transcriptome under various stresses during high-temperature ethanol fermentation, providing rich information for further metabolic engineering towards improved stress tolerance and ethanol production.


Assuntos
Etanol/metabolismo , Fermentação , Temperatura Alta , Kluyveromyces/metabolismo , Estresse Fisiológico , Ácido Acético/metabolismo , Aminoácidos de Cadeia Ramificada/biossíntese , Sequência de Bases , Ciclo do Ácido Cítrico , Glucose/metabolismo , Kluyveromyces/genética , Engenharia Metabólica , Mitocôndrias/metabolismo , NADP/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Análise de Sequência de RNA , Transcriptoma
3.
Plant Biotechnol J ; 16(2): 558-571, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28703450

RESUMO

Cadmium (Cd) is a widespread soil contaminant threatening human health. As an ideal energy plant, sweet sorghum (Sorghum bicolor (L.) Moench) has great potential in phytoremediation of Cd-polluted soils, although the molecular mechanisms are largely unknown. In this study, key factors responsible for differential Cd accumulation between two contrasting sweet sorghum genotypes (high-Cd accumulation one H18, and low-Cd accumulation one L69) were investigated. H18 exhibited a much higher ability of Cd uptake and translocation than L69. Furthermore, Cd uptake through symplasmic pathway and Cd concentrations in xylem sap were both higher in H18 than those in L69. Root anatomy observation found the endodermal apoplasmic barriers were much stronger in L69, which may restrict the Cd loading into xylem. The molecular mechanisms underlying these morpho-physiological traits were further dissected by comparative transcriptome analysis. Many genes involved in cell wall modification and heavy metal transport were found to be Cd-responsive DEGs and/or DEGs between these two genotypes. KEGG pathway analysis found phenylpropanoid biosynthesis pathway was over-represented, indicating this pathway may play important roles in differential Cd accumulation between two genotypes. Based on these results, a schematic representation of main processes involved in differential Cd uptake and translocation in H18 and L69 is proposed, which suggests that higher Cd accumulation in H18 depends on a multilevel coordination of efficient Cd uptake and transport, including efficient root uptake and xylem loading, less root cell wall binding, and weaker endodermal apoplasmic barriers.


Assuntos
Cádmio/metabolismo , Sorghum/metabolismo , Parede Celular/genética , Parede Celular/metabolismo , Sorghum/genética , Transcriptoma/genética
4.
Ecotoxicol Environ Saf ; 145: 391-397, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28759768

RESUMO

Cadmium (Cd) pollution is a worldwide environmental problem which heavily threatens human health and food security. Sorghum, as one of the most promising energy crop, has been considered to be the source of high-quality feedstock for ethanol fuel. Ninety-six sorghum genotypes were investigated under hydroponic conditions to compare their capabilities of Cd-tolerance, accumulation and translocation for their potential in remediation of Cd contamination. Different genotypes varied largely in the tolerance to Cd stress with tolerance indexes ranked from 0.107 to 0.933. Great difference was also found in Cd uptake and accumulation with concentrations ranging from 19.0 to 202.4mg/kg in shoots and 277.0-898.3mg/kg in roots. The total amounts of Cd ranked from 6.1 to 25.8µg per plant and the highest translocation factor was over 4 times higher than the lowest one. The correlation analysis demonstrated that Cd concentration in shoot reflected the ability of Cd translocation and tolerance of sorghum, and the path coefficient analysis indicated that root biomass could be taken as a biomarker to evaluate Cd extraction ability of sorghum. The results in this study can facilitate the restoring of Cd contaminated areas by sorghum.


Assuntos
Adaptação Fisiológica , Cádmio/análise , Poluentes do Solo/análise , Sorghum/metabolismo , Biodegradação Ambiental , Biocombustíveis , Biomassa , Cádmio/metabolismo , Cádmio/toxicidade , Genótipo , Humanos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Poluentes do Solo/metabolismo , Poluentes do Solo/toxicidade , Sorghum/genética , Sorghum/crescimento & desenvolvimento , Especificidade da Espécie
5.
Biochem Biophys Res Commun ; 462(4): 358-64, 2015 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-25964087

RESUMO

Muscarinic acetylcholine receptors (mAChRs) are G protein-coupled receptors (GPCRs) that are activated by the agonists acetylcholine and muscarine and blocked by several antagonists, among them atropine. In mammals five mAChRs (m1-m5) exist of which m1, m3, and m5 are coupled to members of the Gq/11 family and m2 and m4 to members of the Gi/0 family. We have recently shown that Drosophila melanogaster and other arthropods have two mAChRs, named A and B, where the A-type has the same pharmacology as the mammalian mAChRs, while the B-type has a very low affinity to muscarine and no affinity to classical antagonists such as atropine. Here, we find that the D. melanogaster A-type mAChR is coupled to Gq/11 and D. melanogaster B-type mAChR to Gi/0. Furthermore, by comparing the second and third intracellular loops of all animal mAChRs for which the G protein coupling has been established, we could identify several amino acid residues likely to be specific for either Gq/11 or Gi/0 coupling. Using these hallmarks for specific mAChR G protein interaction we found that all protostomes with a sequenced genome have one mAChR coupled to Gq/11 and one to four mAChRs coupled to Gi/0. Furthermore, in protostomes, probably all A-type mAChRs are coupled to Gq/11 and all B-type mAChRs to G0/i.


Assuntos
Isoformas de Proteínas/metabolismo , Receptores Muscarínicos/metabolismo , Sistemas do Segundo Mensageiro , Sequência de Aminoácidos , Animais , Células CHO , Cricetinae , Cricetulus , Drosophila melanogaster , Dados de Sequência Molecular , Isoformas de Proteínas/química , Receptores Muscarínicos/química , Homologia de Sequência de Aminoácidos
6.
BMC Plant Biol ; 15: 63, 2015 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-25848810

RESUMO

BACKGROUND: microRNAs (miRNAs) are implicated in plant development processes and play pivotal roles in plant adaptation to environmental stresses. Salicornia europaea, a salt mash euhalophyte, is a suitable model plant to study salt adaptation mechanisms. S. europaea is also a vegetable, forage, and oilseed that can be used for saline land reclamation and biofuel precursor production on marginal lands. Despite its importance, no miRNA has been identified from S. europaea thus far. RESULTS: Deep sequencing was performed to investigate small RNA transcriptome of S. europaea. Two hundred and ten conserved miRNAs comprising 51 families and 31 novel miRNAs (including seven miRNA star sequences) belonging to 30 families were identified. About half (13 out of 31) of the novel miRNAs were only detected in salt-treated samples. The expression of 43 conserved and 13 novel miRNAs significantly changed in response to salinity. In addition, 53 conserved and 13 novel miRNAs were differentially expressed between the shoots and roots. Furthermore, 306 and 195 S. europaea unigenes were predicted to be targets of 41 conserved and 29 novel miRNA families, respectively. These targets encoded a wide range of proteins, and genes involved in transcription regulation constituted the largest category. Four of these genes encoding laccase, F-box family protein, SAC3/GANP family protein, and NADPH cytochrome P-450 reductase were validated using 5'-RACE. CONCLUSIONS: Our results indicate that specific miRNAs are tightly regulated by salinity in the shoots and/or roots of S. europaea, which may play important roles in salt tolerance of this euhalophyte. The S. europaea salt-responsive miRNAs and miRNAs that target transcription factors, nucleotide binding site-leucine-rich repeat proteins and enzymes involved in lignin biosynthesis as well as carbon and nitrogen metabolism may be applied in genetic engineering of crops with high stress tolerance, and genetic modification of biofuel crops with high biomass and regulatable lignin biosynthesis.


Assuntos
Chenopodiaceae/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , MicroRNAs/genética , RNA de Plantas/genética , Tolerância ao Sal/genética , Sequência de Bases , Chenopodiaceae/efeitos dos fármacos , Sequência Conservada/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Biblioteca Gênica , Redes Reguladoras de Genes/efeitos dos fármacos , MicroRNAs/metabolismo , Anotação de Sequência Molecular , Dados de Sequência Molecular , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA de Plantas/metabolismo , Reprodutibilidade dos Testes , Tolerância ao Sal/efeitos dos fármacos , Cloreto de Sódio/farmacologia , Estatística como Assunto , Transcriptoma/genética
7.
PLoS Biol ; 10(2): e1001262, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22363206

RESUMO

Cell adhesion molecules and downstream growth factor-dependent signaling are critical for brain development and synaptic plasticity, and they have been linked to cognitive function in adult animals. We have previously developed a mimetic peptide (FGL) from the neural cell adhesion molecule (NCAM) that enhances spatial learning and memory in rats. We have now investigated the cellular and molecular basis of this cognitive enhancement, using biochemical, morphological, electrophysiological, and behavioral analyses. We have found that FGL triggers a long-lasting enhancement of synaptic transmission in hippocampal CA1 neurons. This effect is mediated by a facilitated synaptic delivery of AMPA receptors, which is accompanied by enhanced NMDA receptor-dependent long-term potentiation (LTP). Both LTP and cognitive enhancement are mediated by an initial PKC activation, which is followed by persistent CaMKII activation. These results provide a mechanistic link between facilitation of AMPA receptor synaptic delivery and improved hippocampal-dependent learning, induced by a pharmacological cognitive enhancer.


Assuntos
Cognição/fisiologia , Hipocampo/citologia , Potenciação de Longa Duração/efeitos dos fármacos , Moléculas de Adesão de Célula Nervosa/farmacologia , Neurônios/efeitos dos fármacos , Receptores de AMPA/metabolismo , Transmissão Sináptica/efeitos dos fármacos , Análise de Variância , Animais , Western Blotting , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Ensaio de Imunoadsorção Enzimática , Hipocampo/fisiologia , Potenciação de Longa Duração/fisiologia , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Microscopia Eletrônica , Microscopia de Fluorescência , Neurônios/fisiologia , Técnicas de Patch-Clamp , Fosforilação , Proteína Quinase C/metabolismo , Ratos , Ratos Wistar , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Transmissão Sináptica/fisiologia
8.
J Neuroinflammation ; 11: 27, 2014 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-24490798

RESUMO

BACKGROUND: Interleukin 1 (IL-1) is implicated in neuroinflammation, an essential component of neurodegeneration. We evaluated the potential anti-inflammatory effect of a novel peptide antagonist of IL-1 signaling, Ilantide. METHODS: We investigated the binding of Ilantide to IL-1 receptor type I (IL-1RI) using surface plasmon resonance, the inhibition of Il-1ß-induced activation of nuclear factor κB (NF-κB) in HEK-Blue cells that contained an IL-1ß-sensitive reporter, the secretion of TNF-α in macrophages, protection against IL-1-induced apoptosis in neonatal pancreatic islets, and the penetration of Ilantide through the blood-brain barrier using competitive enzyme-linked immunosorbent assay (ELISA). We studied the effects of the peptide on social behavior and memory in rat models of lipopolysaccharide (LPS)- and amyloid-induced neuroinflammation, respectively, and its effect in a rat model of experimental autoimmune enchephalomyelitis. RESULTS: Ilantide bound IL-1RI, inhibited the IL-1ß-induced activation of NF-κB, and inhibited the secretion of TNF-α in vitro. Ilantide protected pancreatic islets from apoptosis in vitro and reduced inflammation in an animal model of arthritis. The peptide penetrated the blood-brain barrier. It reduced the deficits in social activity and memory in LPS- and amyloid-treated animals and delayed the development of experimental autoimmune enchephalomyelitis. CONCLUSIONS: These findings indicate that Ilantide is a novel and potent IL-1RI antagonist that is able to reduce inflammatory damage in the central nervous system and pancreatic islets.


Assuntos
Anti-Inflamatórios/uso terapêutico , Artrite/tratamento farmacológico , Encefalomielite Autoimune Experimental/tratamento farmacológico , Proteína Antagonista do Receptor de Interleucina 1/uso terapêutico , Oligopeptídeos/farmacologia , Oligopeptídeos/uso terapêutico , Animais , Animais Recém-Nascidos , Anti-Inflamatórios/farmacologia , Apoptose/efeitos dos fármacos , Artrite/induzido quimicamente , Células Cultivadas , Cerebelo/citologia , Citocinas/metabolismo , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/induzido quimicamente , Humanos , Proteína Antagonista do Receptor de Interleucina 1/química , Proteína Antagonista do Receptor de Interleucina 1/farmacologia , Lipopolissacarídeos , Masculino , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Ratos , Ratos Wistar , Comportamento Social , Transfecção , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/metabolismo
9.
Cell Mol Life Sci ; 70(17): 3231-42, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23604020

RESUMO

Muscarinic acetylcholine receptors (mAChRs) play a central role in the mammalian nervous system. These receptors are G protein-coupled receptors (GPCRs), which are activated by the agonists acetylcholine and muscarine, and blocked by a variety of antagonists. Mammals have five mAChRs (m1-m5). In this study, we cloned two structurally related GPCRs from the fruit fly Drosophila melanogaster, which, after expression in Chinese hamster ovary cells, proved to be muscarinic acetylcholine receptors. One mAChR (the A-type; encoded by gene CG4356) is activated by acetylcholine (EC50, 5 × 10(-8) M) and muscarine (EC50, 6 × 10(-8) M) and blocked by the classical mAChR antagonists atropine, scopolamine, and 3-quinuclidinyl-benzilate (QNB), while the other (the B-type; encoded by gene CG7918) is also activated by acetylcholine, but has a 1,000-fold lower sensitivity to muscarine, and is not blocked by the antagonists. A- and B-type mAChRs were also cloned and functionally characterized from the red flour beetle Tribolium castaneum. Recently, Haga et al. (Nature 2012, 482: 547-551) published the crystal structure of the human m2 mAChR, revealing 14 amino acid residues forming the binding pocket for QNB. These residues are identical between the human m2 and the D. melanogaster and T. castaneum A-type mAChRs, while many of them are different between the human m2 and the B-type receptors. Using bioinformatics, one orthologue of the A-type and one of the B-type mAChRs could also be found in all other arthropods with a sequenced genome. Protostomes, such as arthropods, and deuterostomes, such as mammals and other vertebrates, belong to two evolutionarily distinct lineages of animal evolution that split about 700 million years ago. We found that animals that originated before this split, such as cnidarians (Hydra), had two A-type mAChRs. From these data we propose a model for the evolution of mAChRs.


Assuntos
Artrópodes/genética , Artrópodes/metabolismo , Drosophila/genética , Drosophila/metabolismo , Receptores Muscarínicos/genética , Receptores Muscarínicos/metabolismo , Animais , Animais Geneticamente Modificados , Sequência de Bases , Células CHO , Cricetinae , Cricetulus , Regulação para Baixo , Humanos , Dados de Sequência Molecular , RNA Mensageiro/genética
10.
J Agric Food Chem ; 72(12): 6463-6470, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38501643

RESUMO

Eugenol, the main component of essential oil from the Syzygium aromaticum clove tree, has great potential as an alternative bioresource feedstock for biosynthesis purposes. Although eugenol degradation to ferulic acid was investigated, an efficient method for directly converting eugenol to targeted natural products has not been established. Herein we identified the inherent inhibitions by simply combining the previously reported ferulic acid biosynthetic pathway and vanillin biosynthetic pathway. To overcome this, we developed a novel biosynthetic pathway for converting eugenol into vanillin, by introducing cinnamoyl-CoA reductase (CCR), which catalyzes conversion of coniferyl aldehyde to feruloyl-CoA. This approach bypasses the need for two catalysts, namely coniferyl aldehyde dehydrogenase and feruloyl-CoA synthetase, thereby eliminating inhibition while simplifying the pathway. To further improve efficiency, we enhanced CCR catalytic efficiency via directed evolution and leveraged an artificialvanillin biosensor for high-throughput screening. Switching the cofactor preference of CCR from NADP+ to NAD+ significantly improved pathway efficiency. This newly designed pathway provides an alternative strategy for efficiently biosynthesizing feruloyl-CoA-derived natural products using eugenol.


Assuntos
Acil Coenzima A , Benzaldeídos , Vias Biossintéticas , Ácidos Cumáricos , Eugenol , Eugenol/metabolismo
11.
Biotechnol Biofuels Bioprod ; 17(1): 93, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961423

RESUMO

BACKGROUND: Polyketide synthases (PKSs) are classified into three types based on their enzyme structures. Among them, type III PKSs, catalyzing the iterative condensation of malonyl-coenzyme A (CoA) with a CoA-linked starter molecule, are important synthases of valuable natural products. However, low efficiency and byproducts formation often limit their applications in recombinant overproduction. RESULTS: Herein, a rapid growth selection system is designed based on the accumulation and derepression of toxic acyl-CoA starter molecule intermediate products, which could be potentially applicable to most type III polyketides biosynthesis. This approach is validated by engineering both chalcone synthases (CHS) and host cell genome, to improve naringenin productions in Escherichia coli. From directed evolution of key enzyme CHS, beneficial mutant with ~ threefold improvement in capability of naringenin biosynthesis was selected and characterized. From directed genome evolution, effect of thioesterases on CHS catalysis is first discovered, expanding our understanding of byproduct formation mechanism in type III PKSs. Taken together, a whole-cell catalyst producing 1082 mg L-1 naringenin in flask with E value (evaluating product specificity) improved from 50.1% to 96.7% is obtained. CONCLUSIONS: The growth selection system has greatly contributed to both enhanced activity and discovery of byproduct formation mechanism in CHS. This research provides new insights in the catalytic mechanisms of CHS and sheds light on engineering highly efficient heterologous bio-factories to produce naringenin, and potentially more high-value type III polyketides, with minimized byproducts formation.

12.
J Biol Chem ; 287(44): 37420-33, 2012 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-22955284

RESUMO

Nectins belong to a family of immunoglobulin (Ig)-like cell-adhesion molecules comprising four members, nectin-1 through nectin-4. Nectins are involved in formation of the mechanical adhesive puncta adherentia junctions of synapses. Nectins share the same overall structural topology with an extracellular region containing three Ig modules, a transmembrane region, and a cytoplasmic region. In nectin-1, the first and second Ig module in the extracellular region are necessary for the trans-interaction with nectin-3 and formation of cis-dimers, respectively. The function of the third Ig module of nectin-1 remains unknown. We here report the structure in solution of the third, membrane-proximal Ig module of mouse nectin-1 (nectin-1 Ig3) solved by means of nuclear magnetic resonance (NMR) spectroscopy. It belongs to the C1 set of the Ig superfamily. Nectin-1 Ig3 was produced as a recombinant protein and induced neurite outgrowth in primary cultures of hippocampal and cerebellar granule neurons, an effect abolished by treatment with the fibroblast growth factor receptor (FGFR) inhibitor SU5402, or by transfection with a dominant-negative FGFR1 construct. We showed by surface plasmon resonance (SPR) analysis that nectin-1 Ig3 directly interacted with various isoforms of FGFR. Nectin-1 Ig3 induced phosphorylation of FGFR1c in the same manner as the whole nectin-1 ectodomain, and promoted survival of cerebellar granule neurons induced to undergo apoptosis. Finally, we constructed a peptide, nectide, by employing in silico modeling of various FGFR ligand-binding sites. Nectide mimicked all the effects of nectin-1 Ig3. We suggest that FGFR is a downstream signaling partner of nectin-1.


Assuntos
Moléculas de Adesão Celular/fisiologia , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Sequência de Aminoácidos , Animais , Apoptose , Moléculas de Adesão Celular/química , Moléculas de Adesão Celular/metabolismo , Sobrevivência Celular , Cristalografia por Raios X , Fator 2 de Crescimento de Fibroblastos/fisiologia , Células HEK293 , Hipocampo/citologia , Humanos , Camundongos , Dados de Sequência Molecular , Nectinas , Neuritos/metabolismo , Neuritos/fisiologia , Neurônios/citologia , Neurônios/fisiologia , Fosforilação , Cultura Primária de Células , Ligação Proteica , Isoformas de Proteínas/química , Isoformas de Proteínas/metabolismo , Processamento de Proteína Pós-Traducional , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Ratos , Ratos Wistar , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/química , Receptores do Fator de Crescimento Derivado de Plaquetas/química , Transdução de Sinais , Ressonância de Plasmônio de Superfície
13.
Cytokine ; 64(1): 112-21, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23972727

RESUMO

Interleukin-4 (IL-4) is a potent antiinflammatory cytokine. However its use in the clinic is hampered by side effects. We here describe the identification of a novel synthetic peptide, termed Ph8, derived from α-helix C of IL-4, which interacts with IL-4 receptor α (IL-4Rα). Employing various cultured genetically engineered cell lines and primary lymphocytes, surface plasmon resonance, qPCR, ELISA and immunoblotting techniques we found that Ph8 bound IL-4Rα and mimicked the anti-inflammatory effects of IL-4 by inhibiting TNF-α production by macrophages in vitro. It induced phosphorylation of STAT6 65kD but inhibited phosphorylation of STAT6 110 kD induced by IL-4 in a B-cell line that expressed the type I receptor. It also inhibited the IL-4-stimulated expression of a STAT6-inducible reporter gene in cells that expressed the type II receptor. Ph8 inhibited the proliferation of Th1/2 cells and downregulated the production of IFN-γ in stimulated Th1 cells. Moreover, Ph8 did not induce any shift in Th1/Th2 profile. This is a favorable effect and it is indicating that Ph8 could block general T cell activation and inflammatory responses without further inducing the side effects generally associated with IL-4 signaling. These data collectively show that Ph8 is only a partial agonist of IL-4 mimicking its desirable properties. In agreement, Ph8 treatment of rats with collagen-induced arthritis, a Th1- and antibody- mediated disease of joint, delayed the manifestation of chronic inflammation and reduced acute inflammation in carrageenan-induced edema. Our findings indicate that Ph8 is a promising potential drug candidate for the treatment of inflammatory diseases.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Subunidade alfa de Receptor de Interleucina-4/metabolismo , Interleucina-4/farmacologia , Fragmentos de Peptídeos/farmacologia , Animais , Artrite Experimental/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Edema/tratamento farmacológico , Células HEK293 , Humanos , Interferon gama/metabolismo , Interleucina-4/análogos & derivados , Interleucina-4/química , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fragmentos de Peptídeos/química , Fosforilação/efeitos dos fármacos , Ligação Proteica , Ratos , Ratos Wistar , Fator de Transcrição STAT6/metabolismo , Células Th1/efeitos dos fármacos , Células Th1/metabolismo , Fator de Necrose Tumoral alfa/biossíntese
14.
FASEB J ; 26(10): 4174-86, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22750515

RESUMO

Neurexin-1 (NRXN1) and neuroligin-1 (NLGN1) are synaptic cell adhesion molecules that connect pre- and postsynaptic neurons at synapses and mediate signaling across the synapse, which modulates synaptic activity and determines the properties of neuronal networks. Defects in the genes encoding NLGN1 have been linked to cognitive diseases such as autism. The roles of both NRXN1 and NLGN1 during synaptogenesis have been studied extensively, but little is known about the role of these molecules in neuritogenesis, which eventually results in neuronal circuitry formation. The present study investigated the neuritogenic effect of NLGN1 in cultures of hippocampal neurons. Our results show that NLGN1, both in soluble and membrane-bound forms, induces neurite outgrowth that depends on the interaction with NRXN1ß and on activation of fibroblast growth factor receptor-1. In addition, we demonstrate that a synthetic peptide, termed neurolide, which is modeled after a part of the binding interface of NLGN1 for NRXN1ß, can bind to NRXN1ß and mimic the biological properties of NLGN1 in vitro.


Assuntos
Moléculas de Adesão Celular Neuronais/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Animais , Moléculas de Adesão Celular , Moléculas de Adesão Celular Neuronais/genética , Linhagem Celular , Células Cultivadas , Hipocampo/citologia , Humanos , Camundongos , Proteínas do Tecido Nervoso/genética , Neuritos/metabolismo , Neurônios/metabolismo , Ratos , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Ressonância de Plasmônio de Superfície
15.
Stress Biol ; 3(1): 26, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37676394

RESUMO

The thermotolerant yeast Kluyveromyces marxianus is known for its potential in high-temperature ethanol fermentation, yet it suffers from excess acetic acid production at elevated temperatures, which hinders ethanol production. To better understand how the yeast responds to acetic acid stress during high-temperature ethanol fermentation, this study investigated its transcriptomic changes under this condition. RNA sequencing (RNA-seq) was used to identify differentially expressed genes (DEGs) and enriched gene ontology (GO) terms and pathways under acetic acid stress. The results showed that 611 genes were differentially expressed, and GO and pathway enrichment analysis revealed that acetic acid stress promoted protein catabolism but repressed protein synthesis during high-temperature fermentation. Protein-protein interaction (PPI) networks were also constructed based on the interactions between proteins coded by the DEGs. Hub genes and key modules in the PPI networks were identified, providing insight into the mechanisms of this yeast's response to acetic acid stress. The findings suggest that the decrease in ethanol production is caused by the imbalance between protein catabolism and protein synthesis. Overall, this study provides valuable insights into the mechanisms of K. marxianus's response to acetic acid stress and highlights the importance of maintaining a proper balance between protein catabolism and protein synthesis for high-temperature ethanol fermentation.

16.
Neurobiol Dis ; 48(3): 533-45, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22842016

RESUMO

The fibroblast growth factor receptor (FGFR) plays a vital role in the development of the nervous system regulating a multitude of cellular processes. One of the interaction partners of the FGFR is the neural cell adhesion molecule (NCAM), which is known to play an important role in neuronal development, regeneration and synaptic plasticity. Thus, simultaneous activation of FGFR- and NCAM-mediated signaling pathways may be expected to affect processes underlying neurodegenerative diseases. We here report the identification of a peptide compound, Enreptin, capable of interacting with both FGFR and NCAM. We demonstrate that this dual specificity agonist induces phosphorylation of FGFR and differentiation and survival of primary neurons in vitro, and that these effects are inhibited by abrogation of both NCAM and FGFR signaling pathways. Furthermore, Enreptin crosses the blood-brain barrier after subcutaneous administration, enhances long-term memory in normal mice and ameliorates memory deficit in mice with induced brain inflammation. Moreover, Enreptin reduces cognitive impairment and neuronal death induced by Aß25-35 in a rat model of Alzheimer's disease, and reduces the mortality rate and clinical signs of experimental autoimmune encephalomyelitis in rats. Thus, Enreptin is an attractive candidate for the treatment of neurological diseases.


Assuntos
Memória/efeitos dos fármacos , Moléculas de Adesão de Célula Nervosa/agonistas , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Oligopeptídeos/farmacologia , Receptores de Fatores de Crescimento de Fibroblastos/agonistas , Animais , Comportamento Animal/efeitos dos fármacos , Encefalopatias/patologia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Transtornos Cognitivos/patologia , Modelos Animais de Doenças , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Neurônios/citologia , Ratos , Ratos Wistar , Ressonância de Plasmônio de Superfície
17.
Zhonghua Yi Xue Za Zhi ; 91(37): 2638-40, 2011 Oct 11.
Artigo em Zh | MEDLINE | ID: mdl-22321931

RESUMO

OBJECTIVE: To observe the efficacy and safety of fascia iliaca compartment block (FICB) with 0.2% ropivacaine in the early analgesia of children with development dislocation of the hip (DDH) undergoing Salter arthroplasty. METHODS: Approved by the hospital ethics committee, a total of 64 DDH children were divided randomly into 2 groups: group F (FICB with ropivacaine 0.2%, 1 ml/kg, max. 30 ml) and group C (FICB with 0.9% normal saline 1 ml/kg, max. 30 ml). The intra-operative doses of fentanyl, PACU (post-anesthesia care unit), CRIES pain score at 1, 4 and 24 h postoperatively, patient satisfaction score and side effects were recorded. RESULTS: The intra-operative doses of fentanyl and PACU were lower. Pain scores at 1, 4 and 24 h postoperatively were lower. And the patient satisfaction score was significantly higher in the FICB group. CONCLUSION: The administration of ropivacaine (0.2%) for FICB in the early analgesia of DDH children has the advantages of safety, precision, long-lasting and convenience.


Assuntos
Amidas/administração & dosagem , Anestésicos Locais/administração & dosagem , Fasciotomia , Luxação Congênita de Quadril/cirurgia , Bloqueio Nervoso/métodos , Criança , Pré-Escolar , Humanos , Medição da Dor , Dor Pós-Operatória , Ropivacaina
18.
Am J Transl Res ; 13(5): 5343-5349, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34150128

RESUMO

OBJECTIVE: To investigate the expression level of serum miRNA-192-5p and its clinical value in the diagnosis and care of patients with multiple myeloma (MM). METHODS: Eighty-eight patients with MM admitted to our hospital from June 2017 to April 2020 were selected as the observation group. In addition, 70 patients who received osteoporosis testing in our hospital in the corresponding period but were excluded from having MM and haematological malignancy were selected as the control group. The relative expression level of serum miRNA-192-5p was detected. The expression level of serum miRNA and its correlation with patient-related clinical parameters were compared and analyzed. The ROC curve was used to analyze its diagnostic efficacy for MM. RESULTS: The relative expression level of serum miRNA-192-5p in MM patients was remarkably lower than that in the control group (P < 0.05); the AUC area of serum miRNA-192-5p in patients with a diagnosis of MM was 0.853, with a cutoff value of 0.72, the sensitivity of 86.30%, and the specificity of 81.20%, P = 0.030. The relative expression level of miRNA-192-5p in the serum of patients with high ß2-MG and creatinine levels was markedly reduced compared to that in patients with low ß2-MG levels (P < 0.05); the relative expression level of miRNA-192-5p in the serum of patients with low hemoglobin and albumin levels was markedly reduced compared to that in patients with normal hemoglobin and albumin (P < 0.05); and there was significantly negative correlation between the relative expression level of miRNA-192-5p in the serum of MM patients and IgG and IgA levels, respectively (P < 0.05). CONCLUSION: miRNA-192-5p may serve as an auxiliary diagnostic tool in the diagnosis of MM. Furthermore, because there is certain correlation between serum miRNA-192-5p and MM progression and prognosis, it may be regarded as a novel marker for MM monitoring.

19.
Foods ; 10(7)2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34202182

RESUMO

The technology for producing bioethanol from sweet sorghum stalks by solid-state fermentation has developed rapidly in recent years, and has many similarities with traditional Chinese liquor production. However, the product from sweet sorghum stalks was lacking in volatile flavors, and the level of harmful contents were uncertain, therefore it could not be sold as liquor. In this study, the protein, fat, and tannin in the clusters and leaves of sweet sorghum were utilized to increase the content of flavor compounds in the ethanol product through the anaerobic fermentation of Saccharomyces cerevisiae. Meanwhile, the silage fermentation method was used to extend the preservation time of the raw materials and to further enhance the flavors of Fen-flavor liquor, with ethyl acetate as the characteristic flavor. The effects of different feedstock groups on ethyl acetate, ethyl lactate, methanol, acetaldehyde, acetal, fusel oil, total acid, and total ester were evaluated by analyzing the chemical composition of different parts of sweet sorghum and determined by gas chromatograph. The effect of different fermentation periods on the volatile flavor of sweet sorghum Baijiu was evaluated. The yield of the characteristic volatile flavor was increased by the extension of the fermentation time. Sweet sorghum Baijiu with a high ester content can be used as a flavoring liquor, blended with liquor with a shorter fermentation period to prepare the finished Fen-flavor Baijiu, conforming to the Chinese national standard for sale.

20.
J Agric Food Chem ; 69(9): 2816-2825, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33629856

RESUMO

Engineering an artificial microbial community for natural product production is a promising strategy. As mono- and dual-culture systems only gave non-detectable or minimal chlorogenic acid (CGA) biosynthesis, here, a polyculture of three recombinant Escherichia coli strains, acting as biosynthetic modules of caffeic acid (CA), quinic acid (QA), and CGA, was designed and used for de novo CGA biosynthesis. An influx transporter of 3-dehydroshikimic acid (DHS)/shikimic acid (SA), ShiA, was introduced into the QA module-a DHS auxotroph. The QA module proportion in the polyculture and CGA production were found to be dependent on ShiA expression, providing an alternative approach for controlling microbial community composition. The polyculture strategy avoids metabolic flux competition in the biosynthesis of two CGA precursors, CA and QA, and allows production improvement by balancing module proportions. The performance of this polyculture approach was superior to that of previously reported approaches of de novo CGA production.


Assuntos
Ácido Clorogênico , Microbiota , Escherichia coli/genética , Engenharia Metabólica , Ácido Quínico
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