ABSTRACT
Effector proteins secreted by bacteria that infect mammalian and plant cells often subdue eukaryotic host cell defenses by simultaneously affecting multiple targets. However, instances when a bacterial effector injected in the competing bacteria sabotage more than a single target have not been reported. Here, we demonstrate that the effector protein, LtaE, translocated by the type IV secretion system from the soil bacterium Lysobacter enzymogenes into the competing bacterium, Pseudomonas protegens, affects several targets, thus disabling the antibacterial defenses of the competitor. One LtaE target is the transcription factor, LuxR1, that regulates biosynthesis of the antimicrobial compound, orfamide A. Another target is the sigma factor, PvdS, required for biosynthesis of another antimicrobial compound, pyoverdine. Deletion of the genes involved in orfamide A and pyoverdine biosynthesis disabled the antibacterial activity of P. protegens, whereas expression of LtaE in P. protegens resulted in the near-complete loss of the antibacterial activity against L. enzymogenes. Mechanistically, LtaE inhibits the assembly of the RNA polymerase complexes with each of these proteins. The ability of LtaE to bind to LuxR1 and PvdS homologs from several Pseudomonas species suggests that it can sabotage defenses of various competitors present in the soil or on plant matter. Our study thus reveals that the multi-target effectors have evolved to subdue cell defenses not only in eukaryotic hosts but also in bacterial competitors.
Subject(s)
Bacterial Proteins , Lysobacter , Pseudomonas , Type IV Secretion Systems , Pseudomonas/genetics , Pseudomonas/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Lysobacter/genetics , Lysobacter/metabolism , Type IV Secretion Systems/genetics , Type IV Secretion Systems/metabolism , Gene Expression Regulation, Bacterial , Oligopeptides/metabolism , Oligopeptides/genetics , Trans-Activators/genetics , Trans-Activators/metabolism , Repressor Proteins/genetics , Repressor Proteins/metabolism , Sigma Factor/genetics , Sigma Factor/metabolismABSTRACT
Delta-opioid receptor protein (OPRD1) is one of the potential targets for treating pain. The presently available opioid agonists are known to cause unnecessary side effects. To discover a novel opioid agonist, our research group has synthesized a chimeric peptide MCRT and proved its potential activity through in vivo analysis. Non-synonymous SNPs (nsSNPs) missense mutations affect the functionality and stability of proteins leading to diseases. The current research was focused on understanding the role of MCRT in restoring the binding tendency of OPRD1 nsSNPs missense mutations on dynamic nature in comparison with Deltorphin-II and morphiceptin. The deleterious effects of nsSNPs were analyzed using various bioinformatics tools for predicting structural, functional, and oncogenic influence. The shortlisted nine nsSNPs were predicted for allergic reactions, domain changes, post-translation modification, multiple sequence alignment, secondary structure, molecular dynamic simulation (MDS), and peptide docking influence. Further, the docked complex of three shortlisted deleterious nsSNPs was analyzed using an MDS study, and the highly deleterious shortlisted nsSNP A149T was further analyzed for higher trajectory analysis. MCRT restored the binding tendency influence caused by nsSNPs on the dynamics of stability, functionality, binding affinity, secondary structure, residues connection, motion, and folding of OPRD1 protein.
Subject(s)
Molecular Docking Simulation , Molecular Dynamics Simulation , Mutation, Missense , Polymorphism, Single Nucleotide , Protein Binding , Receptors, Opioid, delta , Receptors, Opioid, delta/genetics , Receptors, Opioid, delta/chemistry , Receptors, Opioid, delta/metabolism , Humans , Computer Simulation , Amino Acid Sequence , Oligopeptides/chemistry , Oligopeptides/genetics , Oligopeptides/pharmacologyABSTRACT
Insects have about 50 neuropeptide genes and about 70 genes, coding for neuropeptide G protein-coupled receptors (GPCRs). An important, but small family of evolutionarily related insect neuropeptides consists of adipokinetic hormone (AKH), corazonin, and AKH/corazonin-related peptide (ACP). Normally, insects have one specific GPCR for each of these neuropeptides. The tick Ixodes scapularis is not an insect, but belongs to the subphylum Chelicerata, which comprises ticks, scorpions, mites, spiders, and horseshoe crabs. Many of the neuropeptides and neuropeptide GPCRs occurring in insects, also occur in chelicerates, illustrating that insects and chelicerates are evolutionarily closely related. The tick I. scapularis is an ectoparasite and health risk for humans, because it infects its human host with dangerous pathogens during a blood meal. Understanding the biology of ticks will help researchers to prevent tick-borne diseases. By annotating the I. scapularis genome sequence, we previously found that ticks contain as many as five genes, coding for presumed ACP receptors. In the current paper, we cloned these receptors and expressed each of them in Chinese Hamster Ovary (CHO) cells. Each expressed receptor was activated by nanomolar concentrations of ACP, demonstrating that all five receptors were functional ACP receptors. Phylogenetic tree analyses showed that the cloned tick ACP receptors were mostly related to insect ACP receptors and, next, to insect AKH receptors, suggesting that ACP receptor genes and AKH receptor genes originated by gene duplications from a common ancestor. Similar duplications have probably occurred for the ligand genes, during a process of ligand/receptor co-evolution. Interestingly, chelicerates, in contrast to all other arthropods, do not have AKH or AKH receptor genes. Therefore, the ancestor of chelicerates might have lost AKH and AKH receptor genes and functionally replaced them by ACP and ACP receptor genes. For the small family of AKH, ACP, and corazonin receptors and their ligands, gene losses and gene gains occur frequently between the various ecdysozoan clades. Tardigrades, for example, which are well known for their survival in extreme environments, have as many as ten corazonin receptor genes and six corazonin peptide genes, while insects only have one of each, or none.
Subject(s)
Insect Hormones , Ixodes , Neuropeptides , Oligopeptides , Pyrrolidonecarboxylic Acid , Receptors, G-Protein-Coupled , Animals , Neuropeptides/metabolism , Neuropeptides/genetics , Insect Hormones/metabolism , Insect Hormones/genetics , Ixodes/metabolism , Ixodes/genetics , Receptors, G-Protein-Coupled/metabolism , Receptors, G-Protein-Coupled/genetics , Oligopeptides/metabolism , Oligopeptides/genetics , Oligopeptides/chemistry , Pyrrolidonecarboxylic Acid/analogs & derivatives , Pyrrolidonecarboxylic Acid/metabolism , Phylogeny , Amino Acid Sequence , Cricetulus , CHO Cells , Insect Proteins/genetics , Insect Proteins/metabolism , Receptors, Neuropeptide/metabolism , Receptors, Neuropeptide/geneticsABSTRACT
BACKGROUND: Protease 3C (3Cpro) is the only protease encoded in the human hepatitis A virus genome and is considered as a potential target for antiviral drugs due to its critical role in the viral life cycle. Additionally, 3Cpro has been identified as a potent inducer of ferroptosis, a newly described type of cell death. Therefore, studying the molecular mechanism of 3Cpro functioning can provide new insights into viral-host interaction and the biological role of ferroptosis. However, such studies require a reliable technique for producing the functionally active recombinant enzyme. OBJECTIVE: Here, we expressed different modified forms of 3Cpro with a hexahistidine tag on the N- or C-terminus to investigate the applicability of immobilized metal Ion affinity chromatography (IMAC) for producing 3Cpro. METHODS: We expressed the proteins in Escherichia coli and purified them using IMAC, followed by gel permeation chromatography. The enzymatic activity of the produced proteins was assayed using a specific chromogenic substrate. RESULTS: Our findings showed that the introduction and position of the hexahistidine tag did not affect the activity of the enzyme. However, the yield of the target protein was highest for the variant with seven C-terminal residues replaced by a hexahistidine sequence. CONCLUSION: We demonstrated the applicability of our approach for producing recombinant, enzymatically active 3Cpro.
Subject(s)
3C Viral Proteases , Chromatography, Affinity , Escherichia coli , Histidine , Oligopeptides , Histidine/genetics , Histidine/metabolism , Histidine/chemistry , 3C Viral Proteases/chemistry , 3C Viral Proteases/metabolism , Humans , Oligopeptides/genetics , Oligopeptides/chemistry , Oligopeptides/metabolism , Escherichia coli/genetics , Escherichia coli/metabolism , Viral Proteins/genetics , Viral Proteins/chemistry , Viral Proteins/metabolism , Viral Proteins/isolation & purification , Recombinant Proteins/genetics , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism , Recombinant Proteins/isolation & purification , Recombinant Proteins/biosynthesis , Hepatitis A Virus, Human/genetics , Hepatitis A Virus, Human/chemistry , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/isolation & purification , Recombinant Fusion Proteins/metabolism , Recombinant Fusion Proteins/biosynthesis , Cysteine Endopeptidases/genetics , Cysteine Endopeptidases/chemistry , Cysteine Endopeptidases/metabolism , Gene ExpressionABSTRACT
The acquisition of nutrients from host plants by phytopathogenic fungi is critically important for their invasion success. Melampsora larici-populina, an obligate biotrophic pathogenic fungus, causes the poplar leaf rust disease and can severely damage host poplar plants. Previously, we found that oligopeptide transporters (OPTs) have undergone a convergent expansion, which might reflect adaptation to a phytoparasitic lifestyle. Here, we used various methods to evaluate this hypothesis, including conserved motif identification, positive selection signal mining, expression pattern clustering analysis, and neutral selection tests. The motif composition of the five clades in the OPT family differed, and positive selection was observed during clade differentiation. This suggests that OPTs in these five clades may be functionally differentiated, which would increase the range of transported substrates and promote the absorption of more types of nitrogen compounds from the hosts. According to clustering analysis of gene expression patterns, the expression of most genes from the two expanded clades (clade 2 and 4) was up-regulated during the infection of poplar trees, indicating that the expansion of OPTs likely occurred to promote the uptake of oligopeptides from host poplar plants. The MellpOPT4g gene was determined to be under significant balancing selection based on the neutral selection tests, suggesting that it plays a role in the pathogenic process. In conclusion, these three observations provide preliminary evidence supporting our hypothesis, as they indicate that the expansion of OPTs in M. larici-populina has aided the ability of this pathogen to acquire nutrients from host plants.
Subject(s)
Basidiomycota , Fungal Proteins , Oligopeptides , Plant Diseases , Populus , Populus/genetics , Populus/parasitology , Populus/microbiology , Oligopeptides/metabolism , Oligopeptides/genetics , Basidiomycota/genetics , Basidiomycota/pathogenicity , Basidiomycota/metabolism , Plant Diseases/parasitology , Plant Diseases/microbiology , Plant Diseases/genetics , Fungal Proteins/genetics , Fungal Proteins/metabolism , Membrane Transport Proteins/genetics , Membrane Transport Proteins/metabolism , Phylogeny , Adaptation, Physiological/genetics , Gene Expression Regulation, Fungal , Selection, GeneticABSTRACT
Heterogeneity in gene expression is common among clonal cells in bacteria, although the sources and functions of variation often remain unknown. Here, we track cellular heterogeneity in the bacterium Pseudomonas aeruginosa during colony growth by focusing on siderophore gene expression (pyoverdine versus pyochelin) important for iron nutrition. We find that the spatial position of cells within colonies and non-genetic yet heritable differences between cell lineages are significant sources of cellular heterogeneity, while cell pole age and lifespan have no effect. Regarding functions, our results indicate that cells adjust their siderophore investment strategies along a gradient from the colony center to its edge. Moreover, cell lineages with below-average siderophore investment benefit from lineages with above-average siderophore investment, presumably due to siderophore sharing. Our study highlights that single-cell experiments with dual gene expression reporters can identify sources of gene expression variation of interlinked traits and offer explanations for adaptive benefits in bacteria.
Subject(s)
Gene Expression Regulation, Bacterial , Phenols , Pseudomonas aeruginosa , Siderophores , Siderophores/metabolism , Pseudomonas aeruginosa/genetics , Pseudomonas aeruginosa/metabolism , Oligopeptides/metabolism , Oligopeptides/genetics , Iron/metabolism , Thiazoles/metabolismABSTRACT
Short interfering RNA (siRNA) therapeutics have soared in popularity due to their highly selective and potent targeting of faulty genes, providing a non-palliative approach to address diseases. Despite their potential, effective transfection of siRNA into cells requires the assistance of an accompanying vector. Vectors constructed from non-viral materials, while offering safer and non-cytotoxic profiles, often grapple with lackluster loading and delivery efficiencies, necessitating substantial milligram quantities of expensive siRNA to confer the desired downstream effects. We detail the recombinant synthesis of a diverse series of coiled-coil supercharged protein (CSP) biomaterials systematically designed to investigate the impact of two arginine point mutations (Q39R and N61R) and decahistidine tags on liposomal siRNA delivery. The most efficacious variant, N8, exhibits a twofold increase in its affinity to siRNA and achieves a twofold enhancement in transfection activity with minimal cytotoxicity in vitro. Subsequent analysis unveils the destabilizing effect of the Q39R and N61R supercharging mutations and the incorporation of C-terminal decahistidine tags on α-helical secondary structure. Cross-correlational regression analyses reveal that the amount of helical character in these mutants is key in N8's enhanced siRNA complexation and downstream delivery efficiency.
Subject(s)
Histidine , Liposomes , Oligopeptides , RNA, Small Interfering , RNA, Small Interfering/chemistry , RNA, Small Interfering/genetics , RNA, Small Interfering/administration & dosage , Histidine/chemistry , Histidine/genetics , Humans , Liposomes/chemistry , Oligopeptides/chemistry , Oligopeptides/genetics , Transfection/methods , Protein Structure, SecondaryABSTRACT
Ginseng oligopeptides are naturally occurring small-molecule peptides extracted from ginseng that exhibit positive effects on health and longevity. However, the current industrial production of ginseng oligopeptides primarily relies on plant extraction and chemical synthesis. In this study, we proposed a novel genetic engineering approach to produce active ginseng peptides through multicopy tandem insertion (5 and 15 times). The recombinant ginseng peptides were successfully produced from engineered Bacillus subtilis with an increasing yield from 356.55 to 2900 mg/L as the repeats multiple. Additionally, an oxidative stress-induced aging model caused by H2O2 was established to evaluate whether the recombinant ginseng peptides, without enzymatic hydrolysis into individual peptides, also have positive effects on antiaging. The results demonstrated that all two kinds of recombinant ginseng peptides could also delay cellular aging through various mechanisms, such as inhibiting cell cycle arrest, suppressing the expression of pro-inflammatory factors, and enhancing cellular antioxidant capacity.
Subject(s)
Bacillus subtilis , Panax , Bacillus subtilis/genetics , Bacillus subtilis/metabolism , Panax/chemistry , Hydrogen Peroxide/metabolism , Oxidative Stress , Oligopeptides/genetics , Oligopeptides/pharmacology , Oligopeptides/metabolismABSTRACT
The restoration of the function of p53 in tumors is a therapeutic strategy for the highly frequent mutation of the TP53 tumor suppressor gene. P460 is a wild-type peptide derived from the p53 C-terminus and has been proven to be capable of restoring the tumor suppressor function of p53. The poor accumulation of drugs in tumors is a serious hindrance to tumor treatment. For enhancing the activity of P460, the tumor-targeting sequence Arg-Gly-Asp-Arg (RGDR, C-end rule peptide) was introduced into the C-terminus of P460 to generate the new peptide P462. P462 presented better activity than P460 in inhibiting the proliferation of cancer cells and increasing the number of tumor cells undergoing apoptosis. Cell adhesion analysis and tumor imaging results revealed that P462 showed more specific and extensive binding with tumor cells and greater accumulation in tumors than the wild-type peptide. Importantly, treatment with P462 was more efficacious than that with P460 in vivo and was associated with considerably improved tumor-homing activity. This study highlights the importance of the roles of the tumor-homing sequence RGDR in the enhancement in cell attachment and tumor accumulation. The results of this work indicate that P462 could be a novel drug candidate for tumor treatment.
Subject(s)
Antineoplastic Agents , Apoptosis , Tumor Suppressor Protein p53 , Animals , Humans , Mice , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Apoptosis/drug effects , Cell Adhesion/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Mice, Inbred BALB C , Mice, Nude , Neoplasms/drug therapy , Neoplasms/metabolism , Neoplasms/genetics , Neoplasms/pathology , Oligopeptides/pharmacology , Oligopeptides/chemistry , Oligopeptides/metabolism , Oligopeptides/genetics , Peptides/pharmacology , Peptides/metabolism , Peptides/chemistry , Tumor Suppressor Protein p53/metabolism , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/chemistry , Xenograft Model Antitumor AssaysABSTRACT
Introduction: Candida albicans is an opportunistic pathogenic fungus, which frequently causes systemic or local fungal infections in humans. The evolution of its drug-resistant mutants necessitate an urgent development of novel antimicrobial agents. Results: Here, we explored the antimicrobial activity and inhibitory mechanisms of X33 antimicrobial oligopeptide (X33 AMOP) against C. albicans. The oxford cup test results showed that X33 AMOP had strong inhibitory activity against C. albicans, and its MIC and MFC were 0.625 g/L and 2.5 g/L, respectively. Moreover, SEM and TEM showed that X33 AMOP disrupted the integrity of cell membrane. The AKP, ROS, H2O2 and MDA contents increased, while the reducing sugar, soluble protein, and pyruvate contents decreased after the X33 AMOP treatment. This indicated that X33 AMOP could damage the mitochondrial integrity of the cells, thereby disrupting the energy metabolism by inducing oxidative stress in C. albicans. Furthermore, transcriptome analysis showed that X33 AMOP treatment resulted in the differential expression of 1140 genes, among which 532 were up-regulated, and 608 were down-regulated. These DEGs were related to protein, nucleic acid, and carbohydrate metabolism, and their expression changes were consistent with the changes in physiological characteristics. Moreover, we found that X33 AMOP could effectively inhibit the virulence attributes of C. albicans by reducing phospholipase activity and disrupting hypha formation. Discussion: These findings provide the first-ever detailed reference for the inhibitory mechanisms of X33 AMOP against C. albicans and suggest that X33 AMOP is a potential drug candidate for treating C. albicans infections.
Subject(s)
Anti-Infective Agents , Candida albicans , Humans , Hydrogen Peroxide/pharmacology , Hydrogen Peroxide/metabolism , Antifungal Agents/pharmacology , Gene Expression Profiling , Anti-Infective Agents/pharmacology , Oligopeptides/geneticsABSTRACT
NAP (NAPVSIPQ, drug candidate name, davunetide) is the neuroprotective fragment of activity-dependent neuroprotective protein (ADNP). Recent studies identified NAPVSIP as a Src homology 3 (SH3) domain-ligand association site, responsible for controlling signalling pathways regulating the cytoskeleton. Furthermore, the SIP motif in NAP/ADNP was identified as crucial for direct microtubule end-binding protein interaction facilitating microtubule dynamics and Tau microtubule interaction, at the microtubule end-binding protein site EB1 and EB3. Most de novo ADNP mutations reveal heterozygous STOP or frameshift STOP aberrations, driving the autistic/intellectual disability-related ADNP syndrome. Here, we report for the first time on a de novo missense mutation, resulting in ADNP containing NAPVISPQE instead of NAPVSIPQQ, in a child presenting developmental hypotonia, possibly associated with inflammation affecting food intake in early life coupled with fear of peer interactions and suggestive of a novel case of the ADNP syndrome. In silico modelling showed that the mutation Q (polar side chain) to E (negative side chain) affected the electrostatic characteristics of ADNP (reducing, while scattering the electrostatic positive patch). Comparison with the most prevalent pathogenic ADNP mutation, p.Tyr719*, indicated a further reduction in the electrostatic patch. Previously, exogenous NAP partially ameliorated deficits associated with ADNP p.Tyr719* mutations in transfected cells and in CRISPR/Cas9 genome edited cell and mouse models. These findings stress the importance of the NAP sequence in ADNP and as a future putative therapy for the ADNP syndrome.
Subject(s)
Nerve Tissue Proteins , Point Mutation , Mice , Animals , Nerve Tissue Proteins/genetics , Oligopeptides/genetics , Oligopeptides/metabolism , Oligopeptides/therapeutic use , Microtubules/metabolism , Homeodomain Proteins/genetics , Homeodomain Proteins/metabolismABSTRACT
The introduction of clinical exome sequencing (ES) has provided a unique opportunity to decrease the diagnostic odyssey for patients living with a rare genetic disease (RGD). ES has been shown to provide a diagnosis in 29%-57% of patients with a suspected RGD, with as many as 70% remaining undiagnosed. There is a need to advance the clinical model of care by more formally integrating approaches that were previously considered research into an enhanced diagnostic workflow. We developed an Exome Clinic, which set out to evaluate a workflow for improving the diagnostic yield of ES for patients with an undiagnosed RGD. Here, we report the outcomes of 47 families who underwent clinical ES in the first year of the clinic. The diagnostic yield from clinical ES was 40% (19/47). Families who remained undiagnosed after ES had the opportunity for follow-up studies that included phenotyping and candidate variant segregation in relatives, genomic matchmaking, and ES reanalysis. This enhanced diagnostic workflow increased the diagnostic yield to 55% (26/47), predominantly through the resolution of variants and genes of uncertain significance. We advocate that this approach be integrated into mainstream clinical practice and highlight the importance of a coordinated translational approach for patients with RGD.
Subject(s)
Genomics , Rare Diseases , Humans , Exome Sequencing , Canada , Rare Diseases/diagnosis , Rare Diseases/genetics , Oligopeptides/genetics , Genetic TestingABSTRACT
The adipokinetic hormone/corazonin-related peptide (ACP) is an insect neuropeptide structurally intermediate between corazonin (CRZ) and adipokinetic hormone (AKH). Unlike the AKH and CRZ signaling systems that are widely known for their roles in the mobilization of energy substrates and stress responses, respectively, the main role of ACP and its receptor (ACPR) remains unclear in most arthropods. The current study aimed to localize the distribution of ACP in the nervous system and provide insight into its physiological roles in the disease vector mosquito, Aedes aegypti. Immunohistochemical analysis and fluorescence in situ hybridization localized the ACP peptide and transcript within a number of cells in the central nervous system, including two pairs of laterally positioned neurons in the protocerebrum of the brain and a few ventrally localized neurons within the pro- and mesothoracic regions of the fused thoracic ganglia. Further, extensive ACP-immunoreactive axonal projections with prominent blebs and varicosities were observed traversing the abdominal ganglia. Given the prominent enrichment of ACPR expression within the abdominal ganglia of adult A. aegypti mosquitoes as determined previously, the current results indicate that ACP may function as a neurotransmitter and/or neuromodulator facilitating communication between the brain and posterior regions of the nervous system. In an effort to elucidate a functional role for ACP signaling, biochemical measurement of energy substrates in female mosquitoes revealed a reduction in abdominal fat body in response to ACP that matched the actions of AKH, but interestingly, a corresponding hypertrehalosaemic effect was only found in response to AKH since ACP did not influence circulating carbohydrate levels. Comparatively, both ACP and AKH led to a significant increase in haemolymph carbohydrate levels in male mosquitoes while both peptides had no influence on their glycogen stores. Neither ACP nor AKH influenced circulating or stored lipid levels in both male and female mosquitoes. Collectively, these results reveal ACP signaling in mosquitoes may have complex sex-specific actions, and future research should aim to expand knowledge on the role of this understudied neuropeptide.
Subject(s)
Aedes , Insect Hormones , Neuropeptides , Humans , Animals , Male , Female , Aedes/genetics , Aedes/metabolism , In Situ Hybridization, Fluorescence , Mosquito Vectors , Phylogeny , Insect Hormones/genetics , Insect Hormones/metabolism , Pyrrolidonecarboxylic Acid/metabolism , Oligopeptides/genetics , Oligopeptides/metabolism , Neuropeptides/genetics , Neuropeptides/metabolism , CarbohydratesABSTRACT
The balance between cell proliferation and differentiation in the cambium defines the formation of plant vascular tissues. As cambium cells proliferate, subsets of daughter cells differentiate into xylem or phloem. TDIF-PXY/TDR signaling is central to this process. TDIF, encoded by CLE41 and CLE44, activates PXY/TDR receptors to maintain proliferative cambium. Light and water are necessary for photosynthesis; thus, vascular differentiation must occur upon light perception to facilitate the transport of water and minerals to the photosynthetic tissues. However, the molecular mechanism controlling vascular differentiation in response to light remains elusive. In this study we show that the accumulation of PIF transcription factors in the dark promotes TDIF signaling and inhibits vascular cell differentiation. On the contrary, PIF inactivation by light leads to a decay in TDIF activity, which induces vascular cell differentiation. Our study connects light to vascular differentiation and highlights the importance of this crosstalk to fine-tune water transport.
Subject(s)
Arabidopsis Proteins , Arabidopsis , Arabidopsis/metabolism , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Cell Differentiation , Gene Expression Regulation, Plant , Oligopeptides/genetics , Water , Xylem/metabolismABSTRACT
The bacterial agent of Lyme disease, Borrelia burgdorferi, relies on an intricate gene regulatory network to transit between the disparate Ixodes tick vector and mammalian host environments. We recently reported that a B. burgdorferi mutant lacking a transcriptionally active intergenic region of lp17 displayed attenuated murine tissue colonization and pathogenesis due to altered expression of multiple antigens. In this study, a more detailed characterization of the putative regulatory factor encoded by the intergenic region was pursued. In cis complemented strains featuring mutations aimed at eliminating potential protein translation were capable of full tissue colonization, suggesting that the functional product encoded by the intergenic region is not a protein as previously predicted. In trans complementation of the intergenic region resulted in elevated transcription of the sequence compared to wild type and was found to completely abolish infectivity in both immunocompetent "and immunodeficient mice. Quantitative analysis of transcription of the intergenic region by wild-type B. burgdorferi showed it to be highly induced during murine infection relative to in vitro culture. Lastly, targeted deletion of this intergenic region resulted in significant changes to the transcriptome, including genes with potential roles in transmission and host adaptation. The findings reported herein strongly suggest that this segment of lp17 serves a potentially critical role in the regulation of genes required for adaptation and persistence of the pathogen in a mammalian host.
Subject(s)
Borrelia burgdorferi , Ixodes , Lyme Disease , Animals , Arthropod Proteins/genetics , Arthropod Proteins/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Borrelia burgdorferi/genetics , Borrelia burgdorferi/metabolism , DNA, Intergenic/genetics , Host Adaptation , Ixodes/microbiology , Lyme Disease/genetics , Lyme Disease/metabolism , Lyme Disease/microbiology , Mice , Oligopeptides/genetics , Oligopeptides/metabolismABSTRACT
Xylanases are widely used in the degradation of lignocellulose and are important industrial enzymes. Therefore, increasing the catalytic activity of xylanases can improve their efficiency and performance. In this study, we introduced the C-terminal proline-rich oligopeptide of the rumen-derived XynA into XylR, a GH10 family xylanase. The optimum temperature and pH of the fused enzyme (XylR-Fu) were consistent with those of XylR; however, its catalytic efficiency was 2.48-fold higher than that of XylR. Although the proline-rich oligopeptide did not change the enzyme hydrolysis mode, the amount of oligosaccharides released from beechwood xylan by XylR-Fu was 17% higher than that released by XylR. This increase may be due to the abundance of proline in the oligopeptide, which plays an important role in substrate binding. Furthermore, circular dichroism analysis indicated that the proline-rich oligopeptide might increase the rigidity of the overall structure, thereby enhancing the affinity to the substrate and catalytic activity of the enzyme. Our study shows that the proline-rich oligopeptide enhances the catalytic efficiency of GH10 xylanases and provides a better understanding of the C-terminal oligopeptide-function relationships. This knowledge can guide the rational design of GH10 xylanases to improve their catalytic activity and provides clues for further applications of xylanases in industry.
Subject(s)
Endo-1,4-beta Xylanases , Proline , Animals , Endo-1,4-beta Xylanases/genetics , Endo-1,4-beta Xylanases/metabolism , Enzyme Stability , Oligopeptides/genetics , Substrate Specificity , Xylans/metabolismABSTRACT
BACKGROUND: Autoimmune thyroid diseases (AITDs) are chronic autoimmune diseases specific to thyroid and mainly include Graves' disease (GD) and Hashimoto' thyroiditis (HT). The adaptive immunoreactivity of CD4+ T cells plays a crucial role in the pathogenesis of AITDs, but very little has been known about its changes in disease status. METHODS: We collected peripheral CD4+ T cells from 12 GD patients, including 6 newly diagnosed GD (NGD) and 6 refractory GD (RGD) patients, 6 HT patients and 6 healthy controls, and examined the gene expression profiles and colon types of T cells receptor (TCR) ß chain complementarity determining region 3 (CDR3) using high-throughput sequencing. RESULTS: The TCR repertoire were significantly expanded in AITDs groups, and some TCR genes were expressed more preferentially in AITDs group than in the healthy control group, including TRBV15 (P = 0.001), TRBV4-2 (P = 0.003), TRBV9 (P = 0.007), TRBV3-2 (P = 0.012), TRBV7-8 (P = 0.015), TRBV25-1 (P = 0.019), TRBV12-4 (P = 0.019) and TRBV27 (P = 0.02) in GD patients as well as TRBV29-1 (P = 0.004), TRBV12-4 (P = 0.004), TRBV6-5 (P = 0.011), TRBV7-2 (P = 0.012), TRBV27 (P = 0.012), TRBV9 (P = 0.031) and TRBV4-2 (P = 0.032) in HT patients. Moreover, subgroup analysis showed that the difference in the TCR spectrum between the normal group and NGD was not obvious, but a large number of differential genes appeared in the RGD group. CONCLUSION: TCR spectrum has changed in patients with AITDs with expanded repertoire and many upregulated TRBV genes. Moreover, this difference is not apparent in GD patients at the initial stage, but as the disease progresses, the differences in TCR profiles became more pronounced.
Subject(s)
Autoimmune Diseases , Graves Disease , Hashimoto Disease , Autoimmune Diseases/genetics , Graves Disease/genetics , Graves Disease/pathology , Hashimoto Disease/genetics , High-Throughput Nucleotide Sequencing , Humans , Oligopeptides/genetics , Receptors, Antigen, T-Cell/geneticsABSTRACT
The intestine is a central regulator of metabolic homeostasis. Dietary inputs are absorbed through the gut, which senses their nutritional value and relays hormonal information to other organs to coordinate systemic energy balance. However, the gut-derived hormones affecting metabolic and behavioral responses are poorly defined. Here we show that the endocrine cells of the Drosophila gut sense nutrient stress through a mechanism that involves the TOR pathway and in response secrete the peptide hormone allatostatin C, a Drosophila somatostatin homolog. Gut-derived allatostatin C induces secretion of glucagon-like adipokinetic hormone to coordinate food intake and energy mobilization. Loss of gut Allatostatin C or its receptor in the adipokinetic-hormone-producing cells impairs lipid and sugar mobilization during fasting, leading to hypoglycemia. Our findings illustrate a nutrient-responsive endocrine mechanism that maintains energy homeostasis under nutrient-stress conditions, a function that is essential to health and whose failure can lead to metabolic disorders.
Subject(s)
Drosophila Proteins/metabolism , Eating/physiology , Energy Metabolism/physiology , Gastrointestinal Hormones/metabolism , Homeostasis , Nutrients/metabolism , Somatostatin/metabolism , Animals , Animals, Genetically Modified , Drosophila Proteins/genetics , Drosophila melanogaster/genetics , Drosophila melanogaster/metabolism , Eating/genetics , Energy Metabolism/genetics , Enteroendocrine Cells/metabolism , Gastrointestinal Hormones/genetics , Gene Knockout Techniques , Humans , Hypoglycemia/genetics , Hypoglycemia/metabolism , Insect Hormones/genetics , Insect Hormones/metabolism , Oligopeptides/genetics , Oligopeptides/metabolism , Pyrrolidonecarboxylic Acid/analogs & derivatives , Pyrrolidonecarboxylic Acid/metabolism , Receptors, G-Protein-Coupled/genetics , Receptors, G-Protein-Coupled/metabolism , Signal Transduction/genetics , Somatostatin/genetics , Survival AnalysisABSTRACT
Animals properly perform sexual behaviors by using multiple sensory cues. However, neural mechanisms integrating multiple sensory cues and regulating motivation for sexual behaviors remain unclear. Here, we focused on peptidergic neurons, terminal nerve gonadotropin-releasing hormone (TN-GnRH) neurons, which receive inputs from various sensory systems and co-express neuropeptide FF (NPFF) in addition to GnRH. Our behavioral analyses using knockout medaka of GnRH (gnrh3) and/or NPFF (npff) demonstrated that some sexual behavioral repertoires were delayed, not disrupted, in gnrh3 and npff single knockout males, while the double knockout appeared to alleviate the significant defects that were observed in single knockouts. We also found anatomical evidence to show that both neuropeptides modulate the sexual behavior-controlling brain areas. Furthermore, we demonstrated that NPFF activates neurons in the preoptic area via indirect pathway, which is considered to induce the increase in motivation for male sexual behaviors. Considering these results, we propose a novel mechanism by which co-existing peptides of the TN-GnRH neurons, NPFF, and GnRH3 coordinately modulate certain neuronal circuit for the control of behavioral motivation. Our results may go a long way toward understanding the functional significance of peptidergic neuromodulation in response to sensory information from the external environments.
Subject(s)
Gonadotropin-Releasing Hormone/physiology , Oligopeptides/physiology , Oryzias , Pyrrolidonecarboxylic Acid/analogs & derivatives , Sexual Behavior, Animal/physiology , Amino Acid Sequence , Animals , Base Sequence , Brain/metabolism , Brain Chemistry , Female , Gene Knockout Techniques , Gonadotropin-Releasing Hormone/analysis , Gonadotropin-Releasing Hormone/genetics , Male , Neurons/chemistry , Neurons/physiology , Oligopeptides/analysis , Oligopeptides/genetics , Phylogeny , Pyrrolidonecarboxylic Acid/analysis , Sequence AlignmentABSTRACT
ETHNOPHARMACOLOGICAL RELEVANCE: As a traditional Chinese formula, Liujunzi Decoction (LJZD) originated from the Yi Xue Zheng Zhuan, and has a promising effect in treating chemotherapy-induced anorexia (CIA). AIM OF THE STUDY: The present study aims to investigate whether LJZD acts on interleukin-6 (IL-6)/leptin mediated janus kinase (JAK)-signal transducer and activator of transcription (STAT) signaling pathway that regulates hypothalamus anorexigenic and orexigenic peptides to ameliorate CIA, and also elucidates the potential mechanism by metabolomic analysis. MATERIALS AND METHODS: Network pharmacology analyses were conducted to screen out potential targets and pathways. The CIA rat model was established via an intraperitoneal injection of cisplatin. The histological changes of gastric antrum, liver and ileum were observed by HE staining. The serum levels of leptin, ghrelin, IL-6 and growth differentiation factor 15 (GDF15) were measured by ELISA. The JAK1/2 and STAT levels in gastric antrum and hypothalamus were detected by Western blot. The transcriptions of gastric antrum and hypothalamus IL-6R mRNA, and hypothalamus cocaine- and amphetamine-regulated transcript (CART), pro-opiomelanocortin (POMC), thyrotropin-releasing hormone (TRH), upregulated orexigenic peptides neuropeptide Y (NPY), and agouti-related protein (AGRP) mRNA were assessed by RT-qPCR. The blood samples of control, model and high dose LJZD groups were analyzed by metabolomic. RESULTS: Network pharmacology highlighted the IL-6/leptin mediated JAK-STAT signaling pathway, which regulated downstream anorexigenic and orexigenic peptides in hypothalamus. LJZD ameliorated CIA via stimulating food intake and water consumption in rats. Cisplatin-induced gastric antrum, liver, ileum injuries were ameliorated, serum leptin level reduction was elevated, and ghrelin, IL-6, GDF15 level increases were decreased after LJZD treatments. In gastric antrum and hypothalamus, LJZD inhibited cisplatin-induced activation of JAK-STAT signaling pathway, downregulated the transcriptions of downstream anorexigenic peptides CART, POMC, TRH, and upregulated orexigenic peptides NPY, AGRP in hypothalamus. Importantly, the effect of LJZD in treating CIA might partly relate to the improvements of 23 abnormal metabolites. CONCLUSION: This study implies that inhibiting JAK-STAT signaling pathway, regulating the expressions of anorexigenic and orexigenic peptides, and mediating various metabolic pathways might be potential mechanisms of LJZD's effect against CIA.