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Archives of Iranian Medicine Jul 2014Maize is a member of the Poaceae family, capable of producing large amounts of pollen grains which may constitute important allergens in spring and summer. The aim of...
BACKGROUND
Maize is a member of the Poaceae family, capable of producing large amounts of pollen grains which may constitute important allergens in spring and summer. The aim of this study was to determine the protein content of maize pollen and its allergenicity in guinea pigs.
METHODS
The morphology of maize pollens was determined using light microscopy and scanning electron microscopy. The size of separated proteins was obtained by SDS-PAGE. A group of animals were immunized with maize pollen extract and the others were kept as control. After 40 days, the skin prick test was done in animals after blood sampling for counting the eosinophils. The allergenisity of proteins was identified by immunoblotting of transferred bonds using sera from sensitized guinea pigs.
RESULTS
Pollen grains showed a spherical, monoporate structure with the scabrate exine surface. The SDS-PAGE indicated a major band of about 50 kD.We also showed increase in flare and wheal diameter following skin prick test in sensitized guinea pigs along with an elevated number of eosinophils. The presence of group 13 allergen (Zea m13) with molecular weight of ~ 50 kD was found in immunoblotting results.
CONCLUSION
This study showed one protein in maize pollen extract that could be considered as an allergen belonging to group 13 of allergen categories. However, further investigations should be scheduled for precise analysis of the proteins. This allergen can be used for diagnostic or therapeutic purposes (vaccination approaches) in allergic asthma patients.
Topics: Allergens; Animals; Guinea Pigs; Immunization; Iran; Microscopy, Electron, Scanning; Pollen; Skin Tests; Zea mays
PubMed: 24979562
DOI: No ID Found -
American Journal of Botany Dec 2017Apertures in pollen grains are key structures of the wall, involved in pollen tube germination and exchanges with the environment. Aperture types in angiosperms are...
PREMISE OF THE STUDY
Apertures in pollen grains are key structures of the wall, involved in pollen tube germination and exchanges with the environment. Aperture types in angiosperms are diverse, but pollen with one and three apertures (including monosulcate and tricolpate, respectively) are the two most common types. Here, we investigate the phylogenetic distribution in angiosperms of pollen with many round, scattered apertures called pantoporate pollen.
METHODS
We constructed a morphological data set with species producing pantoporate pollen and representative angiosperm species with other pollen types, sampled from every angiosperm order, with a total of 1260 species distributed in 330 families. This data set was analyzed with parsimony to characterize the phylogenetic distribution of pantoporate pollen in angiosperms.
KEY RESULTS
We show that pantoporate pollen is distributed throughout most of the angiosperm tree, including early diverging angiosperms, monocots, and eudicots. However, this pollen type is usually restricted to a few species in a given group, and is seldom fixed at large taxonomical scales, with a few notable exceptions.
CONCLUSIONS
Pantoporate pollen evolved many times during angiosperm history, but the persistence of this morphology in the long term is infrequent. This distribution pattern could indicate conflicting short-term and long-term selective pressures, pantoporate pollen being selected in the short run, but eliminated in the long run. Biological hypotheses supporting this scenario are discussed, in the context of both theoretical and empirical data on pollen biology.
Topics: Biological Evolution; Magnoliopsida; Models, Genetic; Pollen
PubMed: 29217673
DOI: 10.3732/ajb.1700289 -
Applied Spectroscopy Mar 2013Fourier transform infrared photoacoustic spectroscopy (FT-IR-PAS) has been applied to the problem of identifying pollen samples. One hundred measurements were made on a...
Fourier transform infrared photoacoustic spectroscopy (FT-IR-PAS) has been applied to the problem of identifying pollen samples. One hundred measurements were made on a set of pollen samples comprising five families and ten species. Chemometric analysis of the resulting spectra showed evidence of clustering. Construction of a spectral library allowed pollens in the set to be correctly identified as the first match on the basis of photoacoustic spectra at the species (99%) or family (100%) level.
Topics: Cluster Analysis; Plants; Pollen; Principal Component Analysis; Spectroscopy, Fourier Transform Infrared
PubMed: 23452500
DOI: 10.1366/12-06622 -
Annals of Botany Sep 2011For the Solanaceae-type self-incompatibility, also possessed by Rosaceae and Plantaginaceae, the specificity of self/non-self interactions between pollen and pistil is... (Review)
Review
BACKGROUND
For the Solanaceae-type self-incompatibility, also possessed by Rosaceae and Plantaginaceae, the specificity of self/non-self interactions between pollen and pistil is controlled by two polymorphic genes at the S-locus: the S-locus F-box gene (SLF or SFB) controls pollen specificity and the S-RNase gene controls pistil specificity.
SCOPE
This review focuses on the work from the authors' laboratory using Petunia inflata (Solanaceae) as a model. Here, recent results on the identification and functional studies of S-RNase and SLF are summarized and a protein-degradation model is proposed to explain the biochemical mechanism for specific rejection of self-pollen tubes by the pistil.
CONCLUSIONS
The protein-degradation model invokes specific degradation of non-self S-RNases in the pollen tube mediated by an SLF, and can explain compatible versus incompatible pollination and the phenomenon of competitive interaction, where SI breaks down in pollen carrying two different S-alleles. In Solanaceae, Plantaginaceae and subfamily Maloideae of Rosaceae, there also exist multiple S-locus-linked SLF/SFB-like genes that potentially function as the pollen S-gene. To date, only three such genes, all in P. inflata, have been examined, and they do not function as the pollen S-gene in the S-genotype backgrounds tested. Interestingly, subfamily Prunoideae of Rosaceae appears to possess only a single SLF/SFB gene, and competitive interaction, observed in Solanaceae, Plantaginaceae and subfamily Maloideae, has not been observed. Thus, although the cytotoxic function of S-RNase is an integral part of SI in Solanaceae, Plantaginaceae and Rosaceae, the function of SLF/SFB may have diverged. This highlights the complexity of the S-RNase-based SI mechanism. The review concludes by discussing some key experiments that will further advance our understanding of this self/non-self discrimination mechanism.
Topics: Organ Specificity; Petunia; Plant Proteins; Pollen; Ribonucleases; Self-Incompatibility in Flowering Plants
PubMed: 21193481
DOI: 10.1093/aob/mcq253 -
Proceedings of the National Academy of... Apr 1995
Topics: Cell Communication; Cytoskeleton; Plant Development; Plant Physiological Phenomena; Plants; Pollen; Reproduction; Signal Transduction
PubMed: 7724518
DOI: 10.1073/pnas.92.8.3077 -
Materials Horizons Apr 2023Spores and pollens refer to the reproductive cells of seed plants and asexually reproducing sporophytes, exhibiting a natural core-shell structure and exquisite surface... (Review)
Review
Spores and pollens refer to the reproductive cells of seed plants and asexually reproducing sporophytes, exhibiting a natural core-shell structure and exquisite surface morphology. They possess extraordinary dimensional homogeneity, porosity, amphiphilicity and adhesion. Their sporopollenin exine layer endows them with chemically stable, UV resistant, and biocompatible properties, which can also be facilely functionalized due to sufficient groups on the surface. The unique characteristics of spores and pollens have facilitated a wide range of applications in drug carriers, biological imaging, food science, microrobotics, environmental purification, flexible electronics, cell scaffolds, 3D printing materials and biological detection. This review showcases the common structural composition and physicochemical properties of spores and pollens, describes the extraction and processing methods, and summarizes the recent research on their applications in various fields. Following these sections, this review analyzes the existing challenges in spores and pollen research and provides a future outlook.
Topics: Pollen; Spores
PubMed: 36637068
DOI: 10.1039/d2mh01236g -
Pakistan Journal of Biological Sciences... Jan 2021<b>Background and Objective:</b> Date-Palm trees (<i>Phoenix dactylifera</i> L.) are the most abundant crop in Saudi Arabia. Date Palm Pollen...
<b>Background and Objective:</b> Date-Palm trees (<i>Phoenix dactylifera</i> L.) are the most abundant crop in Saudi Arabia. Date Palm Pollen (DPP) are considered an important allergens. The reasons for the increase in susceptibility to allergy are not clear. This investigation aimed to link the size, shape, moisture contents and biogenic contents of the collected pollens to susceptibility. <b>Materials and Methods:</b> Pollens were collected from three different regions in the Kingdom. Date palm pollen sizes were determined in wet and dry states by Microtrac. A microscope with a camera was used to image the forms of date palm pollens. The biogenic amines were determined after extraction using HPLC. Data were analyzed by one-way analysis of variance (ANOVA), using SPSS version 16.0. <b>Results:</b> There was a variation in the sizes of pollens from different regions ranging between 3.3-704 μm. Most pollen grains are spherical. The concentrations of six biogenic amines were detected in all samples but with different concentrations. They included B-phenyl ethylamine, Putrescine, Cadaverine, Histamine, Tyramine and Spermidine. <b>Conclusion:</b> The shape and size of the pollen grains studied were variable and will not facilitate deep penetration into the respiratory system but their biogenic contents were very high and suggested to cause allergy.
Topics: Analysis of Variance; Chromatography, High Pressure Liquid; Humans; Particulate Matter; Phoeniceae; Pollen; Respiratory System; Rhinitis, Allergic, Seasonal; Saudi Arabia
PubMed: 34486317
DOI: 10.3923/pjbs.2021.326.334 -
The Plant Cell Sep 2008Many plants have a genetically determined self-incompatibility system in which the rejection of self pollen grains is controlled by alleles of an S locus. A common...
Many plants have a genetically determined self-incompatibility system in which the rejection of self pollen grains is controlled by alleles of an S locus. A common feature of these S loci is that separate pollen- and style-expressed genes (pollen S and style S, respectively) determine S allele identity. The long-held view has been that pollen S and style S must be a coevolving gene pair in order for allelic recognition to be maintained as new S alleles arise. In at least three plant families, the Solanaceae, Rosaceae, and Plantaginaceae, the style S gene has long been known to encode an extracellular ribonuclease called the S-RNase. Pollen S in these families has more recently been identified and encodes an F-box protein known as either SLF or SFB. In this perspective, we describe the puzzling evolutionary relationship that exists between the SLF/SFB and S-RNase genes and show that in most cases cognate pairs of genes are not coevolving in the expected manner. Because some pollen S genes appear to have arisen much more recently than their style S cognates, we conclude that either some pollen S genes have been falsely identified or that there is a major problem with our understanding of how the S locus evolves.
Topics: Alleles; F-Box Proteins; Fertility; Gene Expression Regulation, Plant; Plant Proteins; Pollen; Pollination; Ribonucleases
PubMed: 18776062
DOI: 10.1105/tpc.108.060327 -
International Journal of Molecular... 2012Since the primordial of humanity, pollen has been considered a good source of nutrients and energy. Its promising healing properties have also been referred to. The...
Since the primordial of humanity, pollen has been considered a good source of nutrients and energy. Its promising healing properties have also been referred to. The present study aimed to characterize, for the first time, eight commercial pollens from Portugal and Spain available on the market studying the legislation on labeling, pollinic origin, physicochemical and microbiological analyses and identification of yeasts. Eleven botanical families were found amongst the samples. The most abundant family and the most dominant pollen was Cistaceae. The moisture content, ash, a(w), pH, reducing sugars, carbohydrates, proteins, lipids and energy were analyzed and the specific parameters were within the specifications required by some countries with legislation regarding these parameters. Microbiologically commercial pollen showed acceptable safety for the commercial quality and hygiene. All samples showed negative results for toxigenic species. The microorganisms studied were aerobic mesophiles, yeasts and moulds, coliforms, Escherichia coli, Staphylococcus aureus, Salmonella and sulfite-reducing Clostridium. During the work, six yeasts species were isolated from pollen, with Rhodotorula mucilaginosa being the most abundant, as it was present in four samples.
Topics: Animals; Bees; Dietary Supplements; Food Labeling; Pollen; Yeasts
PubMed: 23109845
DOI: 10.3390/ijms130911173 -
Annals of Agricultural and... 2000In this study, pollen grains were identified by use of Durham sampler in the atmosphere of Balikesir in 1996 and 1997. During these two years, a total of 17,256 pollen...
In this study, pollen grains were identified by use of Durham sampler in the atmosphere of Balikesir in 1996 and 1997. During these two years, a total of 17,256 pollen grains per cm(2) were recorded. A total of 8,576 pollen grains per cm(2) were identified in 1996 and a total of 8,680 pollen grains per cm(2) in 1997. Pollen fall in the years 1996-1997 comprised grains belonging to 50 taxa and unidentified pollen grains. Of these 50 taxa, 30 belonged to arboreal and 20 to non-arboreal plants. Total pollen grains consisted of 70.92% grains from arboreal plants, 24.87% grains from non-arboreal plants and 4.21% unidentified pollen grains. In the region investigated, Pinus spp., Cupressaceae/Taxaceae, Gramineae, Platanus spp., Quercus spp., Olea spp., Salix spp., Urticaceae, Moraceae, Plantago spp., Chenopodiaceae/Amaranthaceae, Ailanthus spp., Juglans spp., Carpinus spp. and Rosaceae released the greatest amounts of pollens. During the study period, the pollen fall reached its highest level in May.
Topics: Air Pollutants; Cell Count; Plant Cells; Plant Stems; Plants; Pollen; Species Specificity; Time; Turkey
PubMed: 10865238
DOI: No ID Found