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Advanced Science (Weinheim,... Sep 2023Harmful algal blooms (HABs), which are promoted by eutrophication and intensified by global warming, occur worldwide. Allelochemicals, which are natural chemicals...
Harmful algal blooms (HABs), which are promoted by eutrophication and intensified by global warming, occur worldwide. Allelochemicals, which are natural chemicals derived from plants or microbes, are emerging weapons to eliminate these blooms. However, the cost and technical challenges have limited the discovery of novel antialgal allelochemicals. Herein, the decomposition of agricultural straws is manipulated by white-rot fungi and achieved elevated antialgal efficiency. The transcriptomic analysis reveals that nutrient limitation activated fungal decomposition. By using a comparative nontarget metabolomics approach, a new type of allelochemical sphingosines (including sphinganine, phytosphingosine, sphingosine, and N-acetylsphingosine) is identified. These novel natural algaecides exhibit superior antialgal capability, with as high as an order of magnitude lower effective concentration on blooming species than other prevalent allelochemicals. The co-expression relationship between transcriptomic and metabolomic results indicate that sphinganine is strongly correlated with the differentially expressed lignocellulose degradation unigenes. The algal growth suppression is triggered by the activation of programmed cell death, malfunction of algal photosystem and antioxidant system, the disruption on CO assimilation and light absorption. The sphingosines reported here are a new category of allelochemicals in addition to the well-known antialgal natural chemicals, which are potential species-specific agents for HABs control identified by multi-omics methodology.
Topics: Sphingosine; Herbicides; Pheromones; Fungi
PubMed: 37400420
DOI: 10.1002/advs.202300569 -
Insects Nov 2023In eastern North America, apple orchards are often attacked by several species of tortricid moths (Lepidoptera), including , , , and . Sex pheromones are routinely used...
In eastern North America, apple orchards are often attacked by several species of tortricid moths (Lepidoptera), including , , , and . Sex pheromones are routinely used to monitor male moth populations. Adding plant volatiles to monitoring traps could increase the capture of moths of both sexes and improve the effectiveness of mating disruption systems. This study sought to quantify the attraction of adults of four tortricid moth species to five olfactory treatments, namely (1) Pherocon CM L2-P, (2) Pherocon Megalure CM 4K Dual (=Megalure), (3) Megalure + benzaldehyde, (4) TRE 2266 (linalool oxide + ()-4,8-dimethyl-1,3,7-nonatriene (DMNT)), and (5) TRE 2267 (linalool oxide + DMNT + benzaldehyde), in non-mating disrupted commercial apple orchards in Massachusetts. The commercial lure Megalure was attractive to both sexes of and . The addition of benzaldehyde to TRE 2266 or to Megalure significantly increased the capture of male during the mid and late season of 2021. Only when benzaldehyde was added to TRE 2266 did the latter lure attract in 2020 and 2021. The greatest number of tortricid moths (all four species combined) was captured by TRE 2267. This finding highlights the opportunity to enhance the attractiveness of a commercial lure through the addition of benzaldehyde, an aromatic compound, to Megalure. The potential of these additional volatiles to detect moths in a mating-disrupted orchard and/or remove female moths as a component of a management system is discussed.
PubMed: 37999083
DOI: 10.3390/insects14110884 -
Bio-protocol Oct 2023The cell cycle is a vital process of cell division that is required to sustain life. Since faithful cell division is critical for the proper growth and development of an...
The cell cycle is a vital process of cell division that is required to sustain life. Since faithful cell division is critical for the proper growth and development of an organism, the study of the cell cycle becomes a fundamental research objective. has been an excellent unicellular system for unraveling the secrets of cell division, and the process of synchronization in budding yeast has been standardized. Cell synchronization is a crucial step of cell cycle analysis, where cells in a culture at different stages of the cell cycle are arrested to the same phase and, upon release, they progress synchronously. The cellular synchronization of is easily achieved by a pheromone or other chemicals like hydroxyurea treatment; however, such methodologies seem to be ineffective in synchronizing cells of multimorphic fungi such as . is a human pathogen that can grow in yeast, pseudohyphal, and hyphal forms; these forms differ in morphology as well as cell cycle progression. More importantly, upon subjecting to DNA replication inhibitors for synchronization, develops hyphal structures and grows asynchronously. Therefore, here we describe a simple and easy method to synchronize cells in the G1 phase and the subsequent analysis of cell cycle progression by using flow cytometry.
PubMed: 37900111
DOI: 10.21769/BioProtoc.4848 -
Proceedings of the National Academy of... Sep 2023Chemical signals from conspecifics are essential in insect group formation and maintenance. Migratory locusts use the aggregation pheromone 4-vinylanisole (4VA),...
Chemical signals from conspecifics are essential in insect group formation and maintenance. Migratory locusts use the aggregation pheromone 4-vinylanisole (4VA), specifically released by gregarious locusts, to attract and recruit conspecific individuals, leading to the formation of large-scale swarms. However, how 4VA contributes to the transition from solitary phase to gregarious phase remains unclear. We investigated the occurrence of locust behavioral phase changes in the presence and absence of 4VA perception. The findings indicated that solitary locusts require crowding for 48 and 72 h to adopt partial and analogous gregarious behavior. However, exposure to increased concentrations of 4VA enabled solitary locusts to display behavioral changes within 24 h of crowding. Crowded solitary locusts with RNAi knockdown of , the specific olfactory receptor for 4VA, failed to exhibit gregarious behaviors. Conversely, the knockdown of in gregarious locusts resulted in the appearance of solitary behavior. Additionally, a multi-individual behavioral assay system was developed to evaluate the interactions among locust individuals, and four behavioral parameters representing the inclination and conduct of social interactions were positively correlated with the process of crowding. Our data indicated that exposure to 4VA accelerated the behavioral transition from solitary phase to gregarious phase by enhancing the propensity toward proximity and body contact among conspecific individuals. These results highlight the crucial roles of 4VA in the behavioral phase transition of locusts. Furthermore, this study offers valuable insights into the mechanisms of behavioral plasticity that promote the formation of locust swarms and suggests the potential for 4VA application in locust control.
Topics: Grasshoppers; Animal Communication; Behavior, Animal; Receptors, Odorant; Styrenes
PubMed: 37669362
DOI: 10.1073/pnas.2306659120 -
International Journal of Molecular... Sep 2023Receptor-interference (Receptor-i) is a novel technology used to identify bioactive peptides as agonists or antagonists against a specific receptor, primarily targeting...
Receptor-interference (Receptor-i) is a novel technology used to identify bioactive peptides as agonists or antagonists against a specific receptor, primarily targeting G-protein-coupled receptors (GPCRs). Using Receptor-i methodology, we targeted the pheromone biosynthesis activating neuropeptide receptor (PBAN-R) of the red imported fire ant (). Based on previous studies, we selected four bioactive peptides cyclized with two cysteines: CVKLGSHFC, CIQQGSHFC, CERVGSHFC, and CMARYMSAC, and we conducted small-scale feeding bioassays, measuring fire ant worker mortality. All peptides reduced ant survival; however, CMARYMSAC (MARY) and CIQQGSHFC (IQQG) were the most effective and were selected for feeding trials against large, fully functional fire ant field colonies containing queen, brood, and up to 8000 workers. At the end of the experiment, day 84, synthetic peptide MARY killed over 80% of the workers and two of four queens. IQQG killed over 70% of the workers and three of four queens. The surviving two MARY queens lost an average of 21% of their starting weight. The surviving IQQG queen lost 31% of its weight. In contrast, control colony queens gained an average of 11% of their starting weight. These results provide proof-of-concept for the Receptor-i technology and will synergize applications to other agricultural and medical pests.
Topics: Animals; Ants; Peptides; Agriculture; Biological Assay; Cysteine; Insecticides
PubMed: 37762281
DOI: 10.3390/ijms241813978 -
Cell Jul 2023Ants communicate via large arrays of pheromones and possess expanded, highly complex olfactory systems, with antennal lobes in the brain comprising up to ∼500...
Ants communicate via large arrays of pheromones and possess expanded, highly complex olfactory systems, with antennal lobes in the brain comprising up to ∼500 glomeruli. This expansion implies that odors could activate hundreds of glomeruli, which would pose challenges for higher-order processing. To study this problem, we generated transgenic ants expressing the genetically encoded calcium indicator GCaMP in olfactory sensory neurons. Using two-photon imaging, we mapped complete glomerular responses to four ant alarm pheromones. Alarm pheromones robustly activated ≤6 glomeruli, and activity maps for the three pheromones inducing panic alarm in our study species converged on a single glomerulus. These results demonstrate that, rather than using broadly tuned combinatorial encoding, ants employ precise, narrowly tuned, and stereotyped representations of alarm pheromones. The identification of a central sensory hub glomerulus for alarm behavior suggests that a simple neural architecture is sufficient to translate pheromone perception into behavioral outputs.
Topics: Animals; Ants; Brain; Odorants; Pheromones; Smell; Behavior, Animal
PubMed: 37321218
DOI: 10.1016/j.cell.2023.05.025 -
PloS One 2023Organic volatiles produced by fruits can result in overestimation of sweetness by humans, but it is unknown if a comparable phenomenon occurs in other species. Honey...
Organic volatiles produced by fruits can result in overestimation of sweetness by humans, but it is unknown if a comparable phenomenon occurs in other species. Honey bees collect nectar of varying sweetness at different flowering plants. Bees discriminate sugar concentration and generally prefer higher concentrations; they encounter floral volatiles as they collect nectar, suggesting that they, like humans, could be susceptible to sweetness enhancement by odorant. In this study, limonene, linalool, geraniol, and 6-methyl-5-hepten-2-ol were tested for their ability to alter behaviors related to perception of sweetness by honey bees. Honey bees were tested in the laboratory using proboscis extension response-based assays and in the field using feeder-based assays. In the laboratory assays, 6-methyl-5-hepten-2-ol and geraniol, but neither linalool nor limonene, significantly increased responses to low concentrations of sucrose compared with no odorant conditions in 15-day and 25-day-old adult worker honey bees, but not in 35-day-old bees. Limonene reduced responding in 15-day-old bees, but not in the older bees. There was no odorant-based difference in performance in field assays comparing geraniol and limonene with a no odorant control. The interaction of the tested plant volatiles with sucrose concentration revealed in laboratory testing is therefore unlikely to be a major determinant of nectar choice by honey bees foraging under natural conditions. Because geraniol is a component of honey bee Nasonov gland pheromone as well as a floral volatile, its impact on responses in the laboratory may reflect conveyance of different information than the other odorants tested.
Topics: Humans; Bees; Animals; Plant Nectar; Odorants; Limonene; Sucrose; Perception
PubMed: 38150461
DOI: 10.1371/journal.pone.0290129 -
Frontiers in Physiology 2023Farnesol was identified 20 years ago in a search for quorum sensing molecules (QSM), but there is still uncertainty regarding many aspects of its mode of action...
Farnesol was identified 20 years ago in a search for quorum sensing molecules (QSM), but there is still uncertainty regarding many aspects of its mode of action including whether it employs farnesol transport mechanisms other than diffusion. Based on the structural similarity between farnesol and the farnesylated portion of the pheromone, we explored the effects of ploidy and mating type locus () on the antifungal activity of exogenous farnesol. We approached this question by examining five and five haploid strains with regard to their farnesol sensitivity in comparison to six heterozygous diploids. We examined the haploid and diploid strains for percent cell death after exposure of exponentially growing cells to 0-200 µM farnesol. The heterozygous ( /α) diploids were tolerant of exogenous farnesol whereas the and α haploids were on average 2- and 4-times more sensitive, respectively. In the critical range from 10-40 µM farnesol their cell death values were in the ratio of 1:2:4. Very similar results were obtained with two matched sets of , α, and /α strains. We propose that the observed dependence of farnesol is based on differentially regulated mechanisms of entry and efflux which determine the actual cellular concentration of farnesol. The mechanisms by which pathogens such as tolerate the otherwise lethal effects of farnesol embrace a wide range of physiological functions, including type, ubiquinone type (UQ6-UQ9), energy availability, and aerobic/anaerobic status.
PubMed: 38054042
DOI: 10.3389/fphys.2023.1207567 -
International Journal of Molecular... Nov 2023Pheromone-binding proteins (PBPs) play important roles in binding and transporting sex pheromones. However, the genes identified in coleopteran insects and their...
Pheromone-binding proteins (PBPs) play important roles in binding and transporting sex pheromones. However, the genes identified in coleopteran insects and their information sensing mechanism are largely unknown. (Coleoptera: Curculionidae) is a major insect pest of bamboo plantations. In this study, a novel gene, , from was functionally characterized. was more abundantly expressed in the antennae of both sexes than other body parts, and its expression level was significantly male-biased. Fluorescence competitive binding assays showed that CbuqPBP2 exhibited the strongest binding affinity to dibutyl phthalate ( = 6.32 μM), followed by styrene ( = 11.37 μM), among twelve volatiles. CbuqPBP2, on the other hand, showed high binding affinity to linalool ( = 10.55), the main volatile of host plant . Furthermore, molecular docking also demonstrated the strong binding ability of CbuqPBP2 to dibutyl phthalate, styrene, and linalool, with binding energy values of -5.7, -6.6, and -6.0 kcal/mol, respectively, and hydrophobic interactions were the prevailing forces. The knockdown of expression via RNA interference significantly reduced the electroantennography (EAG) responses of male adults to dibutyl phthalate and styrene. In conclusion, these results will be conducive to understanding the olfactory mechanisms of and promoting the development of novel strategies for controlling this insect pest.
Topics: Female; Animals; Male; Carrier Proteins; Coleoptera; Weevils; Pheromones; Dibutyl Phthalate; Molecular Docking Simulation; Styrenes; Insect Proteins; Moths; Receptors, Odorant; Protein Binding
PubMed: 38069247
DOI: 10.3390/ijms242316925 -
Bioengineering (Basel, Switzerland) Jul 2023A wealth of causal relationships exists in biological systems, both causal brain networks and causal protein signaling networks are very classical causal biological...
A wealth of causal relationships exists in biological systems, both causal brain networks and causal protein signaling networks are very classical causal biological networks (CBNs). Learning CBNs from biological signal data reliably is a critical problem today. However, most of the existing methods are not excellent enough in terms of accuracy and time performance, and tend to fall into local optima because they do not take full advantage of global information. In this paper, we propose a parallel ant colony optimization algorithm to learn causal biological networks from biological signal data, called PACO. Specifically, PACO first maps the construction of CBNs to ants, then searches for CBNs in parallel by simulating multiple groups of ants foraging, and finally obtains the optimal CBN through pheromone fusion and CBNs fusion between different ant colonies. Extensive experimental results on simulation data sets as well as two real-world data sets, the fMRI signal data set and the Single-cell data set, show that PACO can accurately and efficiently learn CBNs from biological signal data.
PubMed: 37627794
DOI: 10.3390/bioengineering10080909