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Journal of Experimental Botany Feb 2015Sieve tubes serve as transport conduits for photo-assimilates and other resources in angiosperms and are profitable targets for piercing-sucking insects such as aphids.... (Review)
Review
Sieve tubes serve as transport conduits for photo-assimilates and other resources in angiosperms and are profitable targets for piercing-sucking insects such as aphids. Sieve-tube sap also contains significant amounts of proteins with diverse functions, for example in signalling, metabolism, and defence. The identification of salivary proteases in Acyrthosiphon pisum led to the hypothesis that aphids might be able to digest these proteins and by doing so suppress plant defence and access additional nitrogen sources. Here, the scarce knowledge of proteases in aphid saliva is briefly reviewed. In order to provide a better platform for discussion, we conducted a few tests on in vitro protease activity and degradation of sieve-tube sap proteins of Cucurbita maxima by watery saliva. Inhibition of protein degradation by EDTA indicates the presence of different types of proteases (e.g. metalloproteses) in saliva of A. pisum. Proteases in the watery saliva from Macrosiphum euphorbiae and A. pisum were able to degrade the most abundant phloem protein, which is phloem protein 1. Our results provide support for the breakdown of sieve-element proteins by aphid saliva in order to suppress/neutralize the defence responses of the plant and to make proteins of sieve-tube sap accessible as a nitrogen source, as is discussed in detail. Finally, we discuss whether glycosylation of sieve-element proteins and the presence of protease inhibitors may confer partial protection against the proteolytic activity of aphid saliva.
Topics: Animals; Aphids; Peptide Hydrolases; Phloem; Plant Proteins; Proteolysis; Saliva
PubMed: 25540441
DOI: 10.1093/jxb/eru487 -
Protein and Peptide Letters 2018Arthropods such as scorpion, snake, insects, and spider as well as the marine animals like sea anemone and cone snails are venomous animals producing venoms with a... (Review)
Review
BACKGROUND
Arthropods such as scorpion, snake, insects, and spider as well as the marine animals like sea anemone and cone snails are venomous animals producing venoms with a complex mixture of peptide, poly peptides and small proteins. The disulfide rich peptides isolated from these animals are potent substances which specifically and selectively modulate different ion channels. The significant characteristics of these distinctive pharmacologically potent compounds highlights the molecular details of their peptide-ion channels interactions as well as provides the opportunities for the development of novel and natural therapeutic agents to treat various diseases including neurological disorders also. A good deal is going into the understanding of their therapeutic applications by unrevealing their mode of action.
CONCLUSION
In this review, an attempt is made to summarizes the molecular behavior of these venom peptides, their pattern of interactions that how molecular simulation studies are used to investigate the dynamic interaction between these peptides and ion channels, structural prediction of peptide channel complex and calculation of binding free energy.
Topics: Computer Simulation; Ion Channels; Models, Molecular; Peptides; Protein Binding; Thermodynamics; Venoms
PubMed: 29921195
DOI: 10.2174/0929866525666180619095245 -
Oral Diseases Oct 2015Fluid and electrolyte secretions are vital for all epithelia and when aberrant lead to numerous pathophysiological conditions. Electrolyte transport across epithelia... (Review)
Review
Fluid and electrolyte secretions are vital for all epithelia and when aberrant lead to numerous pathophysiological conditions. Electrolyte transport across epithelia generates the osmotic force for fluid movement and is mediated by several membrane proteins expressed on both apical and basolateral poles of epithelial cells. Sodium and chloride are crucial for regulation of fluid secretion, thus regulating salivary volume. Bicarbonate (HCO3-), on the other hand, is the major pH buffer; hence, aberrant HCO3- secretion is a major factor in diseases such as cystic fibrosis (CF) causing altered mucin hydration and solubilization. Here, the structure-function mechanisms of the major membrane transporters involved in salivary duct electrolyte transport are reviewed focusing on transepithelial movement of Cl(-) and HCO3-.
Topics: Animals; Aquaporins; Bicarbonates; Chlorides; Cystic Fibrosis Transmembrane Conductance Regulator; Epithelium; Humans; Ion Transport; Membrane Transport Proteins; Potassium Channels; Saliva; Salivary Ducts; Sodium-Bicarbonate Symporters; Sodium-Hydrogen Exchangers; Sodium-Potassium-Chloride Symporters; Sodium-Potassium-Exchanging ATPase; Sulfate Transporters
PubMed: 24164806
DOI: 10.1111/odi.12201 -
Journal of Separation Science Oct 2021Human whole saliva is a bodily fluid that can be obtained easily by noninvasive techniques. Specimens can be collected by the patient also at home in order to monitor... (Review)
Review
Human whole saliva is a bodily fluid that can be obtained easily by noninvasive techniques. Specimens can be collected by the patient also at home in order to monitor health status and variations of several analytes of clinical interest. The contributions to whole saliva include secretions from salivary glands and, among others, from the gingival crevicular fluid that derives from the epithelial mucosa. Therefore, saliva is currently a relevant diagnostic fluid for many substances, including steroids, nonpeptide hormones, therapeutic drugs, and drugs of abuse. This review at first briefly describes the different contributions to whole saliva. A section illustrates the procedures for the collection, handling, and storage of salivary specimens. Another section describes the present use of whole saliva for diagnostic purposes and its specific utilization for the diagnosis of several local and systemic diseases. The final sections illustrate the future opportunities offered by various not conventional techniques with a focus on the most recent -omic investigations. It describes the various issues that have to be taken into account to avoid false positives and negatives, such as the strength of the experimental plan, the adequacy of the number of samples under study, and the proper choice of controls.
Topics: Biomarkers; Humans; Proteome; Proteomics; Saliva
PubMed: 34350708
DOI: 10.1002/jssc.202100384 -
Methods in Molecular Biology (Clifton,... 2024Infection experiments with Galleria mellonella enable the measurement of virulence that is mediated by secretion systems and their effector proteins in vivo. G....
Infection experiments with Galleria mellonella enable the measurement of virulence that is mediated by secretion systems and their effector proteins in vivo. G. mellonella has an innate immune system and shares similarities with the complex host environment of mammals. Unlike other invertebrate model systems, experiments can be performed at mammalian body temperature. Here, we describe the systemic infection of G. mellonella with Pseudomonas aeruginosa with and without functional secretion systems. A Kaplan-Meier curve is constructed showing the percent survival of animals over time.
Topics: Animals; Bodily Secretions; Body Temperature; Models, Biological; Pseudomonas aeruginosa; Sepsis; Mammals
PubMed: 37930555
DOI: 10.1007/978-1-0716-3445-5_38 -
Annual Review of Microbiology Sep 2019The Apicomplexa phylum includes a large group of obligate intracellular protozoan parasites responsible for important diseases in humans and animals. is a widespread... (Review)
Review
The Apicomplexa phylum includes a large group of obligate intracellular protozoan parasites responsible for important diseases in humans and animals. is a widespread parasite with considerable versatility, and it is capable of infecting virtually any warm-blooded animal, including humans. This outstanding success can be attributed at least in part to an efficient and continuous sensing of the environment, with a ready-to-adapt strategy. This review updates the current understanding of the signals governing the lytic cycle of , with particular focus on egress from infected cells, a key step for balancing survival, multiplication, and spreading in the host. We cover the recent advances in the conceptual framework of regulation of microneme exocytosis that ensures egress, motility, and invasion. Particular emphasis is given to the trigger molecules and signaling cascades regulating exit from host cells.
Topics: Actomyosin; Animals; Bodily Secretions; Calcium Signaling; Cell Adhesion; Cell Movement; Host-Parasite Interactions; Humans; Molecular Motor Proteins; Organelles; Protozoan Proteins; Signal Transduction; Toxoplasma
PubMed: 31500539
DOI: 10.1146/annurev-micro-020518-120235 -
Current Allergy and Asthma Reports Oct 2018IgE is a key player in multiple inflammatory airway diseases. Ample literature demonstrates its presence in mucosa of patients with allergic rhinitis (AR), local... (Review)
Review
PURPOSE OF REVIEW
IgE is a key player in multiple inflammatory airway diseases. Ample literature demonstrates its presence in mucosa of patients with allergic rhinitis (AR), local allergic rhinitis (LAR), asthma, or chronic rhinosinusitis with nasal polyposis (CRSwNP).
RECENT FINDINGS
Current evidence shows that high-affinity IgE in blood stream of allergic individuals derives mainly from the mucosae. Also, mucosal synthesis of IgE can occur in the absence of systemic atopy, and may be relevant in atopic and non-atopic phenotypes of rhinitis as demonstrated in LAR. Specific IgE (sIgE) detection varies depending on technique used for sample collection and its measurement. sIgE detection is highly specific for diagnosis of LAR. Moreover, measurement of sIgE in secretions could be useful in monitoring response to allergen-specific immunotherapy in both AR and LAR phenotypes. This review will focus on recent developments in the role of IgE in respiratory diseases, and the clinical implications of its measurement in secretions.
Topics: Bodily Secretions; Diagnostic Techniques and Procedures; Humans; Immunoglobulin E; Respiratory Mucosa; Rhinitis, Allergic
PubMed: 30317418
DOI: 10.1007/s11882-018-0821-7 -
Nanoscale Jan 2018Cowpea mosaic virus (CPMV) is a plant virus which is being extensively investigated as a drug delivery and vaccine nanocarrier for parenteral administration. However, to...
Cowpea mosaic virus (CPMV) is a plant virus which is being extensively investigated as a drug delivery and vaccine nanocarrier for parenteral administration. However, to date little is known about the suitability of plant-based nanocarriers for oral delivery. In this study, the colloidal (i.e. aggregation), physical (i.e. denaturation) and chemical (i.e. digestion of the polypeptides) stability of CPMV and its empty virus-like particles (eVLPs) in conditions resembling the gastrointestinal fluids were evaluated. The nanoparticles were incubated in various simulated gastric and intestinal fluids and in pig gastric and intestinal fluids. CPMV and eVLPs had similar stabilities. In simulated gastric media, they were stable at pH ≥ 2.5. At lower pH destabilisation of the particle structure occurred, which, in turn, rendered the polypeptides extremely sensitive to pepsin digestion. However, both CPMV and eVLPs were stable in simulated intestinal fluids, in pig gastric fluids and in pig intestinal fluids. Thus CPMV, despite being a protein-based nanoparticle, was much more resistant to the harsh GI conditions than soluble proteins. Remarkably, both CPMV and eVLPs incubated in pig gastric and intestinal fluids were not subject to protein adsorption, with no formation of a detectable protein corona. The lack of a protein corona on CPMV and eVLP surfaces in GI fluids would imply that, if orally administered, these nanoparticles could maintain their native surface characteristics; thus, their biological interactions would remain predictable and unchanged. In summary, CPMV and eVLPs can be considered promising nanocarriers for applications requiring oral delivery, given their chemical, physical and colloidal stability and lack of protein adsorption from the environment in most of the tested conditions.
Topics: Animals; Comovirus; Drug Carriers; Gastric Juice; Hydrogen-Ion Concentration; Intestinal Secretions; Nanoparticles; Peptides; Protein Corona; Swine
PubMed: 29231944
DOI: 10.1039/c7nr07182e -
Free Radical Biology & Medicine Jun 2015In multicellular organisms, some cells are given the task of secreting huge quantities of proteins. To comply with their duty, they generally equip themselves with a... (Review)
Review
In multicellular organisms, some cells are given the task of secreting huge quantities of proteins. To comply with their duty, they generally equip themselves with a highly developed endoplasmic reticulum (ER) and downstream organelles in the secretory pathway. These professional secretors face paramount proteostatic challenges in that they need to couple efficiency and fidelity in their secretory processes. On one hand, stringent quality control (QC) mechanisms operate from the ER onward to check the integrity of the secretome. On the other, the pressure to secrete can be overwhelming, as for instance on antibody-producing cells during infection. Maintaining homeostasis is particularly hard when the products to be released contain disulfide bonds, because oxidative folding entails production of reactive oxygen species. How are redox homeostasis ("redoxtasis") and proteostasis maintained despite the massive fluxes of cargo proteins traversing the pathway? Here we describe recent findings on how ERp44, a multifunctional chaperone of the secretory pathway, can modulate these processes integrating protein QC, redoxtasis, and calcium signaling.
Topics: Amino Acid Sequence; Animals; Endoplasmic Reticulum; Homeostasis; Humans; Immunoglobulins; Membrane Proteins; Molecular Chaperones; Molecular Sequence Data; Oxidation-Reduction; Protein Folding; Secretory Pathway; Sequence Homology, Amino Acid
PubMed: 25744412
DOI: 10.1016/j.freeradbiomed.2015.02.020 -
Reproduction in Domestic Animals =... Apr 2017Peroxidation damage to spermatozoa and seminal plasma has an important role in sperm quality. Thus, the objective of this study was to determine the levels of lipid and...
Peroxidation damage to spermatozoa and seminal plasma has an important role in sperm quality. Thus, the objective of this study was to determine the levels of lipid and protein oxidation in spermatozoa and seminal plasma of Asian elephants (Elephas maximus) with varying percentage of progressive motility. Lipid and protein oxidation was measured by the thiobarbituric acid-reactive species (TBARS) assay and the 2, 4-dinitrophenylhydrazine (DNPH) carbonyl groups assay, respectively. Fresh semen samples were collected from Asian elephants and classified according to the percentage of motile spermatozoa into good (>60%) and poor (≤20%) motility. Results revealed that seminal plasma malondialdehyde (MDA) and seminal plasma protein carbonyls (PCs) were significantly higher in poor motility than in good motility (p < .05). The MDA and PC levels in seminal plasma were negatively correlated with the percentages of progressive motility (p < .05). In addition, the negative correlation between sperm concentration and seminal plasma MDA level was investigated (p < .05). The sperm viability was also negatively correlated with sperm PC level (p < .05). This study indicated that lipid and protein oxidation has deleterious effect on semen quality of Asian elephants.
Topics: Animals; Elephants; Lipid Peroxidation; Lipids; Male; Malondialdehyde; Protein Carbonylation; Proteins; Semen; Spermatozoa
PubMed: 28058745
DOI: 10.1111/rda.12900