[Morphological study of sexual reproductive disorders in Ligusticum chuanxiong].

Chuanxiong Rhizoma is a well-known Sichuan-specific herbal medicine. Its original plant, Ligusticum chuanxiong, has been cultivated asexually for a long time. L. chuanxiong has sexual reproductive disorders, which restricts its germplasm innovation. However, there is little research on the reproductive system of L. chuanxiong. This study is based on a comparative anatomical research approach, using morphological dissection, paraffin sectioning, staining and compression, and combined with scanning electron microscopy technology, to observe and compare the flowers, fruits, and seeds at various stages of reproductive growth of L. chuanxiong and its wild relative L. sinense. The results showed that the meiosis of pollen mother cells is abnormal in L. chuanxiong anthers, and the size and number of microspores are uneven and inconsistent in the tetrad stage. tapetum cells are not completely degenerated during anther development. During the pollen ripening stage, there are fine cracks in the anther wall, while most anthers could not release pollen normally. The surface of mature pollen grains is concave and partially deformed, and the pollens are all inactive and cannot germinate in vitro. The starch, polysaccharides, and lipids in the pollen were insufficient. The filaments of L. chuanxiong are short at the flowering stage and recurved downward. Double-hanging fruits were observed in the fruiting stage, being wrinkled; with shriveled seeds. Compared with L. sinense at the same stage, the anthers of L. sinense developed normally, and the pollen grains are vigorous and can germinate in vitro. The double-hanging fruits of L. sinense are full and normal; at the flowering period, the filaments are long and erect, significantly higher than the stigma. Mature blastocysts are visible in the ovary of both L. chuanxiong and L. sinense, and there is no significant difference in stigmas. The conclusion is that during the development of L. chuanxiong stamens, the meiosis of pollen mother cells is abnormal, and tetrad, tapetum, filament and other pollen structures develop abnormally. L. chuanxiong has the characteristic of male infertility, which is an important reason for its sexual reproductive disorders.

Pollen diet diversity across bee lineages varies with lifestyle rather than colony size.

The shift to a pollen diet and the evolution of more highly organized societies, i.e., eusocial, were key milestones in bee diversification over their evolutionary history, culminating in a high dependence on feeding broods with a large variety of floral resources. Here, we hypothesized that obligatory eusocial bees have a wider diet diversity than their relatives with solitary lifestyles, and this would be related to colony size. To test both hypotheses, we surveyed diet breadth data (palynological analysis) based on the Shannon-Wiener index (H') for 85 bee taxa. We also obtained colony size for 47 eusocial bee species. These data were examined using phylogenetic comparative methods. The results support the generalist strategy as a derived trait for the bee taxa evaluated here. The dietary diversity of eusocial bees (H': 2.1, on average) was 67.5% higher than that of noneusocial bees (H': 1.21, on average). There was, however, no relationship between diet breadth and colony size, indicating that smaller colonies can harvest a pollen variety as diverse as larger colonies. Taken together, these results provide new insights into the impact of lifestyle on the diversity of collected pollen. Furthermore, this work sheds light on an advantage of living in more highly structured societies irrespective of the size of the colony.

Acyl-CoA synthetase 1 plays an important role on pollen development and male fertility in tomato.

The development of pollen is critical to male reproduction in flowering plants. Acyl-CoA synthetase (ACOS) genes play conserved functions in regulating pollen development in various plants. Our previous work found that knockout of the SlACOS1 gene in tomato might decrease fruit setting. The current study further revealed that SlACOS1 was important to pollen development and male fertility. The SlACOS1 gene was preferentially expressed in the stamen of the flower with the highest expression at the tetrad stage of anther development. Mutation of the SlACOS1 gene by the CRISPR/Cas9-editing system reduced pollen number and viability as well as fruit setting. The tapetum layer exhibited premature degradation and the pollen showed abnormal development appearing irregular, shriveled, or anucleate in Slacos1 mutants at the tetrad stage. The fatty acid metabolism in anthers was significantly impacted by mutation of the SlACOS1 gene. Furthermore, targeted fatty acids profiling using GC-MS found that contents of most fatty acids except C18:1 and C18:2 were reduced. Yeast complementation assay demonstrated that the substrate preferences of SlACOS1 were C16:0 and C18:0 fatty acids. Male fertility of Slacos1 mutant could be slightly restored by applying exogenous palmitic acid, a type of C16:0 fatty acid. Taken together, SlACOS1 played important roles on pollen development and male fertility by regulating the fatty acid metabolism and the development of tapetum and tetrad. Our findings will facilitate unraveling the mechanism of pollen development and male fertility in tomato.

[TWO CASES OF ALLERGIC VULVOVAGINITIS DIAGNOSED BY DIRECT MICROSCOPIC URINE SEDIMENT EXAMINATION].

Cedar pollen is known as a typical allergen that causes various allergic symptoms in the nasal mucosa, conjunctiva, and skin. However, inflammation of the vulvar mucosa due to sensitization to cedar pollen is not well-known. We experienced two cases in which the detection of cedar pollen during microscopic urine sediment examination led to the diagnosis of allergic vulvovaginitis caused by cedar pollen. The cases involved a 4-year-old girl and a 10-year-old girl. In both cases, the patients presented with chief complaints of pruritis in the vulva and insomnia due to frequent urination during the season of cedar pollen dissemination. Both patients were afebrile. No inflammatory skin changes such as erythema, swelling, or non-purulent discharge from mucous membranes of the vulva were observed. Microscopic urine sediment examination revealed large amounts of shed cedar pollen. The patients' conditions improved after treatment with oral antihistamines and instruction to dry their underwear indoors. Follow-up blood tests revealed high levels of specific anti-IgE antibodies to cedar pollen, thus confirming a diagnosis of allergic vulvovaginitis due to cedar pollen. Cedar pollen can cause allergic vulvovaginitis. Microscopic urine sediment examination is useful, and when combined with specific IgE antibody testing, leads to an appropriate diagnosis. This disease should also be considered in patients with complaints of vulvar discomfort during the season of cedar pollen dissemination.

Chemical Composition and Nutritional Value of Royal Jelly Samples Obtained from Honey Bee (Apis mellifera) Hives Fed on Oak and Rapeseed Pollen Patties.

Young workers, i.e., nurse honey bees, synthesize and secrete royal jelly to feed the brood and queen. Since royal jelly is a protein-rich substance, the quality of royal jelly may be influenced by the consumption of feed with varying protein content. We tested whether honey bee (Apis mellifera) colonies compensates for the nutritional quality to produce royal jelly by feeding different pollen patties made of oak or rapeseed pollen. After harvesting royal jelly, we examined the chemical composition including proximate nutrients, amino acids, proteins, fatty acids, and minerals of royal jelly samples obtained from two treatments. The results revealed that pollen patties with different nutritional levels did not influence the nutritional composition except for the crude fat. The levels of 10-HDA, which serves as an indicator of the royal jelly quality, showed no significant difference between the oak and rapeseed treatments, with values of 1.9 and 2.1 g/100 g, respectively. However, we found some differences in the protein intensity, particularly the MRJP3 precursor, MRJP3-like, and glucose oxidase. This study suggests that honey bees may have mechanisms to compensate for nutritional standards to meet the brood's and queen's nutritional requirements during bee pollen collection, preserving bee bread and royal jelly secretion.

Comprehensive Embryological Analyses of Common Buckwheat (Fagopyrym esculentum Moench).

Knowledge of detailed reproductive biology of cultivated species is important as requirements for fruit and seed production allow the development of effective management strategies and a sustainable use. Embryological processes of common buckwheat (Fagopyrum esculentum Moench) are difficult to interpret due to the influence of genetic determinants, i.e., dimorphic heterostyly resulting in the production of long- and short-styled flowers, and environmental predisposition, i.e., sensitivity of ovules to thermal stress. Furthermore, the situation is complicated by overproduction of flowers and depletion of resources as the plant ages. Herein we provide protocols that allow to visualize both basic and more specific embryological features and also disturbances in sexual reproduction of common buckwheat resulting from external and internal factors. All stages of plant material fixation, preparation, staining, and observation are described and explained in detail. Technical tips and pictures of properly prepared microscopic sections are also provided.

Flower opening dynamics, pollen-ovule ratio, stigma receptivity and stigmatic pollen germination (in-vivo) in Chaenomeles speciosa (Sweet) Nakai.

Although Chaenomeles is widely used in horticulture, traditional Chinese medicine and landscape greening, insufficient research has hindered its breeding and seed selection. This study investigated the floral phenology, floral organ characteristics, palynology, and breeding systems of Chaenomeles speciosa (Sweet) Nakai. The floral characteristics of C. speciosa were observed both visually and stereoscopically. The microstructures of the flower organs were observed using scanning electron microscopy. Pollen stainability was determined using triphenyl tetrazolium chloride staining. Stigma receptivity was determined using the benzidine-H2O2 method and the post-artificial pollination pollen germination method. The breeding system was assessed based on the outcrossing index and pollen-ovule ratio. The flowers of C. speciosa were bisexual with a flowering period from March to April. The flowering periods of single flowers ranged from 8 to 19 d, and those of single plants lasted 18-20 d. The anthers were cylindrical, with the base attached to the filament, and were split longitudinally to release pollen. The flower had five styles, with a connate base. The ovaries had five carpels and five compartments. The inverted ovules were arranged in two rows on the placental axis. The stigma of C. speciosa was dry and had many papillary protrusions. In the early flowering stage (1-2 d of flowering), the pollen exhibited high stainability (up to 84.24%), but all stainability was lost at 7 d of flowering. Storage at - 20 °C effectively delayed pollen inactivation. The stigma receptivity of C. speciosa lasted for approximately 7 days, and the breeding system was classified as outcrossing with partial self-compatibility.

Gamma irradiation and ozone application as preservation methods for longer-term storage of bee pollen.

Bee pollen is a healthy product with a good nutritional profile and therapeutic properties. Its high moisture content, however, promotes the growth of bacteria, molds, and yeast during storage commonly result in product degradation. Therefore, the aim of this study is to assess the effectiveness of gamma irradiation (GI) and ozone (OZ) as bee pollen preservation methods for longer storage time, as well as whether they are influenced by pollen species. To do that, GI at a dosage of 2.5, 5.0, and 7.5 kGy was applied at a rate of 0.68 kGy/h and OZ application at a concentration of 0.01, 0.02, and 0.03 g/m3 was applied for one time for 6 h, to Egyptian clover and maize bee pollen, then stored at ambient temperature for 6 months. We then determined the total phenolic content (TPC) and antioxidant activity of treated and non-treated pollen samples at 0, 3, and 6 months of storage. Total bacteria, mold, and yeast count were also evaluated at 0, 2, 4, and 6 months. Statistical analyses revealed that, TPC, antioxidant, and microbial load of both clover and maize pollen samples were significantly (p < 0.05) affected by both treatment and storage time and their interaction. Both methods were extremely effective at preserving the antioxidant properties of pollen samples after 6 months of storage at room temperature. Furthermore, the highest concentrations of both GI and OZ applications completely protected pollen samples from mold and yeast while decreasing bacterial contamination. GI at the highest dose (7.5 KGy) was found to be more effective than other GI doses and OZ application in preserving biologically active compounds and lowering the microbial count of pollen samples for 6 months. As a result, we advise beekeepers to use GI at this dose for longer-term storage.

Pollen and sub-pollen particles: External interactions shaping the allergic potential of pollen.

Pollen allergies, such as allergic rhinitis, are triggered by exposure to airborne pollen. They are a considerable global health burden, with their numbers expected to rise in the coming decades due to the advent of climate change and air pollution. The relationships that exist between pollens, meteorological, and environmental conditions are complex due to a lack of clarity on the nature and conditions associated with these interactions; therefore, it is challenging to describe their direct impacts on allergenic potential clearly. This article attempts to review evidence pertaining to the possible influence of meteorological factors and air pollutants on the allergic potential of pollen by studying the interactions that pollen undergoes, from its inception to atmospheric traversal to human exposure. This study classifies the evidence based on the nature of these interactions as physical, chemical, source, and biological, thereby simplifying the complexities in describing these interactions. Physical conditions facilitating pollen rupturing for tree, grass, and weed pollen, along with their mechanisms, are studied. The effects of pollen exposure to air pollutants and their impact on pollen allergenic potential are presented along with the possible outcomes following these interactions, such as pollen fragmentation (SPP generation), deposition of particulate matter on pollen exine, and modification of protein levels in-situ of pollen. This study also delves into evidence on plant-based (source and biological) interactions, which could indirectly influence the allergic potential of pollen. The current state of knowledge, open questions, and a brief overview of future research directions are outlined and discussed. We suggest that future studies should utilise a multi-disciplinary approach to better understand this complex system of pollen interactions that occur in nature.

A novel strategy for the quality control of carbonized Typhae pollen using colorimeter, liquid chromatography-mass spectrometry, and efficacy evaluation coupled with multivariate statistical analysis.

In this study, a novel quality control strategy was proposed, aiming to establish a multivariate specification for the processing step by exploring the correlation between colors, chemical components, and hemostatic effects of the carbonized Typhae pollen (CTP) using multivariate statistical analysis. The CTP samples were stir-fried at different durations. Afterward, the colorimeter and LC-MS techniques were applied to characterize the CTP samples, followed by the determination of bleeding time and clotting time using mice to evaluate their hemostatic effect. Then, principal component analysis, hierarchical cluster analysis, and multi-block partial least squares were used for data analysis on colors, chemical components, and their correlation with the hemostatic effect. Consequently, 13 critical quality attributes (CQAs) of CTP were identified via multivariate statistical analysis-L*, a*, b*, 3,4-dihydroxybenzoic acid, 4-hydroxybenzoic acid, 3-hydroxybenzoic acid, quercetin-3-O-glucoside, azelaic acid, kaempferol-3-O-glucoside, quercetin, naringenin, kaempferol, and isorhamnetin. The multivariate specification method involving the 13 CQAs was developed and visualized in the latent variable space of the partial least squares model, indicating that the proposed method was successfully applied to assess the quality of CTP and the degree of carbonization. Most importantly, this study offers a novel insight into the control of processing for carbonized Chinese herbal medicines.

Revisiting a pollen-transmitted ilarvirus previously associated with angular mosaic of grapevine.

We report the characterization of a novel tri-segmented RNA virus infecting Mercurialis annua, a common crop weed and model species in plant science. The virus, named "Mercurialis latent virus" (MeLaV) was first identified in a mixed infection with the recently described Mercurialis orthotospovirus 1 (MerV1) on symptomatic plants grown in glasshouses in Lausanne (Switzerland). Both viruses were found to be transmitted by Thrips tabaci, which presumably help the inoculation of infected pollen in the case of MeLaV. Complete genome sequencing of the latter revealed a typical ilarviral architecture and close phylogenetic relationship with members of the Ilarvirus subgroup 1. Surprisingly, a short portion of MeLaV replicase was found to be identical to the partial sequence of grapevine angular mosaic virus (GAMV) reported in Greece in the early 1990s. However, we have compiled data that challenge the involvement of GAMV in angular mosaic of grapevine, and we propose alternative causal agents for this disorder. In parallel, three highly-conserved MeLaV isolates were identified in symptomatic leaf samples in The Netherlands, including a herbarium sample collected in 1991. The virus was also traced in diverse RNA sequencing datasets from 2013 to 2020, corresponding to transcriptomic analyses of M. annua and other plant species from five European countries, as well as metaviromics analyses of bees in Belgium. Additional hosts are thus expected for MeLaV, yet we argue that infected pollen grains have likely contaminated several sequencing datasets and may have caused the initial characterization of MeLaV as GAMV.

Pollen chemical and mechanical defences restrict host-plant use by bees.

Plants produce an array of chemical and mechanical defences that provide protection against many herbivores and pathogens. Putatively defensive compounds and structures can even occur in floral rewards: for example, the pollen of some plant taxa contains toxic compounds or possesses conspicuous spines. Yet little is known about whether pollen defences restrict host-plant use by bees. In other words, do bees, like other insect herbivores, tolerate the defences of their specific host plants while being harmed by non-host defences? To answer this question, we compared the effects of a chemical defence from Lupinus (Fabaceae) pollen and a putative mechanical defence (pollen spines) from Asteraceae pollen on larval survival of nine bee species in the tribe Osmiini (Megachilidae) varying in their pollen-host use. We found that both types of pollen defences reduce larval survival rate in some bee species. These detrimental effects were, however, mediated by host-plant associations, with bees being more tolerant of the pollen defences of their hosts, relative to the defences of plant taxa exploited by other species. This pattern strongly suggests that bees are adapted to the pollen defences of their hosts, and that host-plant use by bees is constrained by their ability to tolerate such defences.

Method to develop a regional guide for the allergenic potential of tree pollen.

Allergic rhinitis, caused by airborne pollen, is a common disease with a great impact on the quality of life for patients and high costs for society. Prevention of high pollen concentrations in the air is relevant for creating a safe environment for allergic patients. Due to climate change, the heat in cities during the summer is a recurring problem. The local climate can be improved by using the cooling properties of trees, providing shade and cooling by evapotranspiration. When deciding which tree species will be planted, it is important to take into account the allergenicity of the pollen that the tree produces. Available guides, used all over the world, on the allergenicity of pollen are very divers in content and interpretation and not applicable for the Netherlands. In this study a method is described to develop a guide for the allergenic potential of tree pollen in a region, in this case the Netherlands. For the most common tree species in the Netherlands the scientific knowledge on the allergenicity of the pollen was collected, followed by an inventory on regional pollen abundance. Subsequently, the sensitization pattern in a patient group with possible inhalation allergy was analyzed. Based on these data allergenicity of the tree pollen was classified into five classes. Eight tree species/genera of the 61 most planted tree species in the Netherlands are considered to have a very strong to moderate allergenic potential. We propose to use this methodology to develop regional-specific guides classifying the allergenic potential of tree pollen.

[Study on allergen components of birch pollen in Beijing area].

Objective:To explore the allergen components of birch pollen in the Beijing area and interpret its clinical significance. Methods:A total of 58 patients with birch pollen allergy were included in the cross-sectional study and divided into allergic rhinitis（AR） and allergic asthma（AA） groups according to clinical manifestations. Concentration of birch pollen allergen sIgE, as well as Bet v 1, Bet v 2, Bet v 4 and Bet v 6 sIgE were detected by ImmunoCAP immunolinked immunoassay. Differences of sIgE concentration of birch pollen allergen component in AR and AA were analyzed. Results:There were 44（75.9%） cases of AR and 14（24.1%） cases of AA were enrolled. All the 18 patients with spring pollen allergy were AR patients without AA. There were 40 cases with both spring and autumn pollen allergy, of which 26 cases（65%） were AR and 14 cases（35%） were AA. The sIgE of birch pollen allergen was level 2 or above in all subjects. 94.8% were positive for any four allergen components. 77.6% were mono-sensitized to any allergen component while 17.2% were dual-sensitized. The positive rate of Bet v 1 and/or Bet v 2 was 93.1%. The positive rates of four protein components were: Bet v 1（82.8%）, Bet v 2（29.3%）, Bet v 6（1.7%）, Bet v 4（0%）. sIgE of birch pollen was positively correlated with sIgE level of Betv 1（r=0.898, P<0.001）. The sIgE concentration of Bet v2 in AA group was significantly higher than that in AR group（[4.34±14.35] kUA/L vs [1.56±3.26] kUA/L, P<0.05）. There was no significant difference in other components. Conclusion:Bet v 1 is the main allergen component of birch pollen in the Beijing area, and Bet v 1 plus Bet v 2 can diagnose more than 90% of birch pollen allergy.

Heterogeneity of sensitization profiles and clinical phenotypes among patients with seasonal allergic rhinitis in Southern European countries-The @IT.2020 multicenter study.

BACKGROUND: Pollen allergy poses a significant health and economic burden in Europe. Disease patterns are relatively homogeneous within Central and Northern European countries. However, no study broadly assessed the features of seasonal allergic rhinitis (SAR) across different Southern European countries with a standardized approach. OBJECTIVE: To describe sensitization profiles and clinical phenotypes of pollen allergic patients in nine Southern European cities with a uniform methodological approach. METHODS: Within the @IT.2020 multicenter observational study, pediatric and adult patients suffering from SAR were recruited in nine urban study centers located in seven countries. Clinical questionnaires, skin prick tests (SPT) and specific IgE (sIgE) tests with a customized multiplex assay (Euroimmun Labordiagnostika, Lübeck, Germany) were performed. RESULTS: Three hundred forty-eight children (mean age 13.1 years, SD: 2.4 years) and 467 adults (mean age 35.7 years SD: 10.0 years) with a predominantly moderate to severe, persistent phenotype of SAR were recruited. Grass pollen major allergenic molecules (Phl p 1 and/or Phl p 5) ranged among the top three sensitizers in all study centers. Sensitization profiles were very heterogeneous, considering that patients in Rome were highly poly-sensitized (sIgE to 3.8 major allergenic molecules per patient), while mono-sensitization was prominent and heterogeneous in other cities, such as Marseille (sIgE to Cup a 1: n = 55/80, 68.8%) and Messina (sIgE to Par j 2: n = 47/82, 57.3%). Co-sensitization to perennial allergens, as well as allergic comorbidities also broadly varied between study centers. CONCLUSIONS: In Southern European countries, pollen allergy is heterogeneous in terms of sensitization profiles and clinical manifestations. Despite the complexity, a unique molecular, multiplex, and customized in-vitro IgE test detected relevant sensitization in all study centers. Nevertheless, this geographical diversity in pollen allergic patients imposes localized clinical guidelines and study protocols for clinical trials of SAR in this climatically complex region.

The material basis of bitter constituents in Carbonized Typhae Pollen, based on the integration strategy of constituent analysis, taste sensing system and molecular docking.

The discovery of bitter constituents is of great significance to the exploration of medicinal substances for they have potential physiological effects. Carbonized Typhae Pollen (CTP), which is a typical example of carbonized Traditional Chinese Medicine (TCM), has a bitter taste and hemostatic effect after carbonized processing. The objective of this study is to elucidate the material basis of bitter constituents in CTP. Firstly, the constituents of CTP extracts with 7 different solvents were characterized by UPLC-Q-TOF-MS. Then, multivariate statistical analysis was used to visualize the CTP extracts from 7 solvents. A total of 37 constituents were tentatively identified and 17 constituents were considered as the key constituents in differentiating 7 different solvent extracts. Subsequently, the bitter evaluation of extracts from different polar parts was investigated by using an electronic tongue. As a result, the order of bitterness of the extracts was as follows: ethanol > methanol > water > n-butyl alcohol > petroleum ether > butyl acetate > isopropanol. There were statistically significant differences in the bitter degree of extracts. By correlation analysis of bitter information and chemical constituents with partial least squares regression (PLSR), 8 potential bitterness constituents were discovered, including phenylalanine, valine, chlorogenic acid, isoquercitrin, palmitic acid, citric acid, quercetin-3-O-(2-α-L-rhamnosyl)-rutinoside, and typhaneoside. Additionally, molecular docking analysis was conducted to reveal the interaction of these constituents with the bitter taste receptor. The docking result showed that these constituents could be embedded well into the active pocket of T2R46 and had significant affinity interactions with critical amino acid residues by forming hydrogen bonds. This study provided a reliable theoretical basis for future research on biological activity of bitterness substances.

Three Artemisia pollens trigger the onset of allergic rhinitis via TLR4/MyD88 signaling pathway.

OBJECTIVE: The prevalence of allergic rhinitis is high, making it a relatively common chronic condition. Countless patients suffer from seasonal Allergic rhinitis (AR). The objective of this investigation is to examine the potential involvement of common pollen allergens in seasonal allergic rhinitis, and study the proposed mechanism of Toll-like receptor 4 (TLR4)/Myeloid differentiation primary response gene 88 (MyD88) signaling pathway in the induction of AR. METHOD: A mouse AR model (sensitized group) was constructed with pollen extracts and ovalbumin (OVA) of Artemisia annua (An), Artemisia argyi (Ar) and Artemisia Sieversiana (Si), and thereafter, AR symptom score was performed. After successful modeling, mouse serum and nasal mucosa tissues were extracted for subsequent experiments. The expression levels of immunoglobulin E (IgE), Interleukin (IL)-4, IL-5, IL-13 and Tumor Necrosis Factor-α (TNF-α) in serum were detected using Enzyme-linked immunosorbent assay (ELISA); Hematoxylin-eosin (H&E) staining methods were used to observe the pathological changes of the nasal mucosal tissue; Utilizing immunohistochemistry (IHC) staining, the expression levels of TLR4, MyD88 and Nuclear factor kappa B (NF-κB) p65 in mouse nasal mucosa were quantified; The mRNA and protein expression levels of TLR4, MyD88 and NF-κB p65 in nasal mucosa of sensitized mice were detected with Quantitative reverse transcription PCR (qRT-PCR) and Western Blot. Finally, the in vitro culture of Human nasal mucosal epithelial cells (HNEpC) cells was conducted, and cells were treated with 200 µg/ml Artemisia annua pollen extract and OVA for 24 h. Western Blot assay was used to detect the expression level of TLR4, MyD88 and NF-κB p65 proteins before and after HNEpC cells were treated with MyD88 inhibitor ST-2825. RESULT: On the second day after AR stimulation, the mice showed obvious AR symptoms. H&E results showed that compared to the control group, the nasal mucosal tissue in the sensitized group was significantly more inflamed. Furthermore, ELISA assay showed increased expression levels of IgE, IL-4, IL-5, IL-13 and TNF-α in serum of mice induced by OVA and Artemisia annua pollen, Artemisia argyi pollen and Artemisia Sieversiana pollen than those of the control group. However, the expression level of IL-2 was lower than that of the control group (P < 0.05). Using Immunohistochemistry staining visually observed the expression levels of TLR4, MyD88 and NF-κB p65 in mouse nasal mucosa tissues and quantitatively analyzed. The expression levels of TLR4, MyD88 and NF-κB p65 in the sensitized group were higher than those in the control group, and the differences were statistically significant (P < 0.05). The results from qRT-PCR and Western Blot showed that the mRNA and protein expression levels of TLR4, MyD88 and NF-κB p65 in nasal mucosa of the sensitized group were significantly higher than those in the control group (P < 0.05). Finally, HNEpC cells were cultured in vitro and analyzed using Western Blot. The expression levels of TLR4, MyD88 and NF-κB p65 in OVA and An groups were significantly increased (P < 0.05). After ST-2825 treatment, TLR4 protein expression was significantly increased (P < 0.05) and MyD88 and NF-κB p65 protein expression were significantly decreased (P < 0.05). CONCLUSION: To sum up, the occurrence and development of AR induced by OVA and pollen of Artemisia annua, Artemisia argyi and Artemisia Sieversiana were related to TLR4/MyD88 signal pathway.

The R2R3 MYB gene TaMYB305 positively regulates anther and pollen development in thermo-sensitive male-sterility wheat with Aegilops kotschyi cytoplasm.

MAIN CONCLUSION: The loss of TaMYB305 function down-regulated the expression of jasmonic acid synthesis pathway genes, which may disturb the jasmonic acid synthesis, resulting in abnormal pollen development and reduced fertility. The MYB family, as one of the largest transcription factor families found in plants, regulates plant development, especially the development of anthers. Therefore, it is important to identify potential MYB transcription factors associated with pollen development and to study its role in pollen development. Here, the transcripts of an R2R3 MYB gene TaMYB305 from KTM3315A, a thermo-sensitive cytoplasmic male-sterility line with Aegilops kotschyi cytoplasm (K-TCMS) wheat, was isolated. Quantitative real-time PCR (qRT-PCR) and promoter activity analysis revealed that TaMYB305 was primarily expressed in anthers. The TaMYB305 protein was localized in the nucleus, as determined by subcellular localization analysis. Our data demonstrated that silencing of TaMYB305 was related to abnormal development of stamen, including anther indehiscence and pollen abortion in KAM3315A plants. In addition, TaMYB305-silenced plants exhibited alterations in the transcriptional levels of genes involved in the synthesis of jasmonic acid (JA), indicating that TaMYB305 may regulate the expression of genes related to JA synthesis and play an important role during anther and pollen development of KTM3315A. These results provide novel insight into the function and molecular mechanism of R2R3-MYB genes in pollen development.

Comprehensive analysis of neonicotinoids in Chinese commercial honey and pollen: A corresponding health risk assessment for non-targeted organisms.

Neonicotinoids are broad-spectrum and highly effective insecticides that work by affecting neural activity in insects. Neonicotinoids are systemic pesticides that are absorbed by plants, transported, and accumulated in plant tissues, including nectar and pollen. Currently, there is a lack of a comprehensive assessment of the level of neonicotinoid contamination and the associated health risks to non-targeted organisms in commercial honey and pollen produced in China. This study collected 160 batches of honey and 26 batches of pollen from different regions and plant sources in China, analyzed the residue patterns of neonicotinoid pesticides, and comprehensively evaluated the exposure risks to non-targeted organisms including bees (adults and larvae) and humans. Furthermore, this study addresses this imperative by establishing a high-throughput, rapid, and ultra-sensitive indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) based on broad-spectrum monoclonal antibodies to detect and quantify neonicotinoids, with validation conducted using the LC-MS/MS method. The findings indicated that 59.4 % of honey samples contained at least one of eight neonicotinoids, and the ic-ELISA rapid detection and calculation method could detect all the samples containing neonicotinoids. Additionally, the dietary risk assessment for humans and honeybees indicates that the consumption of a specific quantity of honey may not pose a health risk to human due to neonicotinoid intake. However, the Risk Quotient values for imidacloprid to adult bees and bee larvae, as well as clothianidin to bee larvae, were determined to be 2.22, 5.03, and 1.01, respectively-each exceeding 1. This highlights the elevated risk of acute toxicity posed by imidacloprid and clothianidin residues to honey bees. The study bears significant implications for the safety evaluation of non-targeted organisms in the natural food chain. Moreover, it provides scientific guidance for protecting the diversity and health of the ecosystem.

Investigating the longstanding mystery of stigma length differences between morphs of distylous plants.

Longer stigmas in short-styled morphs of distylous plants have been considered an adaptive characteristic that increases intermorph pollen deposition. The greater pollen deposition in short-styled stigmas may be a by-product of their longer length, making deposition effectiveness comparison between morphs unfeasible. Thus, investigating which morph has the relatively most efficient stigma (i.e., pollen deposition per unit length) can boost our understanding of the adaptive significance of longer stigmas. Here, we compared pollen deposition between morphs relative to stigma length and assessed whether short-styled stigmas are more, less, or equally effective in receiving pollen grains per unit length. We reviewed the literature to characterize the extent of sigma length differences between morphs using the two most speciose distylous genera as model systems: Palicourea and Psychotria (Rubiaceae). Then, we conducted a between-morph comparison of raw and relative pollen depositions in a Palicourea rigida population. We confirmed that short-styled stigmas were longer than long-styled stigmas in both Palicourea (194.31% longer) and Psychotria (52.59% longer) flowers. Furthermore, in the focal Pal. rigida, although short-styled stigmas were 268.04% longer and received 97.04% more pollen grains than long-styled stigmas, the relative pollen deposition had a reverse pattern, with short-styled stigmas being two-times less efficient in receiving pollen. Our results indicate that the longer length of the short-styled stigmas may have a compensatory effect, increasing the chances of pollen grains reaching the stigma and probably maintaining disassortative intermorph pollination in distylous plants.