Scholarly Works, Entomology

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The Chemistry of the Defensive Secretions of Three Species of Millipedes in the Genus Brachycybe
Banks, Paige; Funkhouser, Emma M.; Macias, Angie M.; Lovett, Brian; Meador, Shelby; Hatch, Arden; Garraffo, H. Martin; Cartwright, Kaitie C.; Kasson, Matt T.; Marek, Paul E.; Jones, Tappey H.; Mevers, Emily (Springer, 2024-06-10)
Millipedes have long been known to produce a diverse array of chemical defense agents that deter predation. These compounds, or their precursors, are stored in high concentration within glands (ozadenes) and are released upon disturbance. The subterclass Colobognatha contains four orders of millipedes, all of which are known to produce terpenoid alkaloids—spare the Siphonophorida that produce terpenes. Although these compounds represent some of the most structurally-intriguing millipede-derived natural products, they are the least studied class of millipede defensive secretions. Here, we describe the chemistry of millipede defensive secretions from three species of Brachycybe: Brachycybe producta, Brachycybe petasata, and Brachycybe rosea. Chemical investigations using mass spectrometry-based metabolomics, chemical synthesis, and 2D NMR led to the identification of five alkaloids, three of which are new to the literature. All identified compounds are monoterpene alkaloids with the new compounds representing indolizidine (i.e. hydrogosodesmine) and quinolizidine alkaloids (i.e. homogosodesmine and homo-hydrogosodesmine). The chemical diversity of these compounds tracks the known species phylogeny of this genus, rather than the geographical proximity of the species. The indolizidines and quinolizidines are produced by non-sympatric sister species, B. producta and B. petasata, while deoxybuzonamine is produced by another set of non-sympatric sister species, B. rosea and Brachycybe lecontii. The fidelity between the chemical diversity and phylogeny strongly suggests that millipedes generate these complex defensive agents de novo and begins to provide insights into the evolution of their biochemical pathways.
Neuromodulating Alkaloids from Millipede Defensive Secretions
Menegatti, Carla; Wood, Jared S.; Banks, Paige; Knott, Kenneth; Briganti, Jonathan S.; Briganti, Anthony J.; McNally, Samuel V. G.; Marek, Paul E.; Brown, Anne M.; Jones, Tappey H.; Williamson, R. Thomas; Mevers, Emily (American Chemical Society, 2024)
Millipedes have long been known to produce structurally diverse chemical defenses, including hydrogen cyanide, terpenoid alkaloids, and oxidized aromatics. Although the hydrogen cyanide and oxidized aromatic producing millipedes have been well studied, less than 10% of the terpenoid alkaloid producers have been chemically investigated. Several previous studies have shown that alkaloids disorient predators, but their biochemical target is currently unknown. Herein, we investigated the defensive secretions of a colobognath millipede, Ischnocybe plicata, and elucidated the constitution, absolute configuration, and conformation of four new highly oxidized terpenoid alkaloids, termed ischnocybines, using a range of analytical techniques. The ischnocybines are actively secreted from the defensive glands and were shown to disorient ants, a likely common predator. Evaluation of the ischnocybines in a panel of neuroreceptors revealed that ischnocybine A possesses potent (Ki 13.6 nM) and selective (100-fold) binding affinity for sigma-1, an orphan neuroreceptor, over sigma-2. These molecules represent the most complex alkaloids to be discovered from millipedes and provide the first potential insights into a biochemical target responsible for their defensive properties.
Success takes time: History and current status of biological control of purple loosestrife in the United States
Endriss, Stacy B.; Nuzzo, Victoria; Blossey, Bernd (2022)
Purple loosestrife (Lythrum salicaria, Lythraceae) is a long-lived forb that has negatively affected North American wetlands for decades. Following the introduction of purple loosestrife from Eurasia in the early 1800s, populations gradually spread across North America, eventually leading to the decline of many native birds, plants, and amphibians. Land managers recognized the widespread ecological harm caused by purple loosestrife and called for sustainable control methods, realizing that traditional methods such as chemical treatments had failed to produce desirable outcomes. In response, research to assess biological control options for purple loosestrife began in 1986 in Europe. This biological control program represented one of the first times a plant was targeted for biological control because of its harm to flora and fauna rather than because of its negative impacts to agriculture. This work led to the release of four host-specific insects: two leaf-feeding beetles (Galerucella calmariensis and Galerucella pusilla; both Coleoptera: Chrysomelidae) and a root-feeding weevil (Hylobius transversovittatus; Coleoptera: Curculionidae) in 1992, followed in 1994 by a flower-feeding weevil (Nanophyes marmoratus; Coleoptera: Curculionidae). The Galerucella leaf-feeding beetles now appear to be widely established and abundant. Data on the abundance and distribution of the root-feeding and flowering-feeding weevils remain sparse. The effect of these insects may vary from site to site, but in many regions across North America, such as the Pacific Northwest, the Great Lakes Region, and the Northeast, biological control of purple loosestrife is now highly effective and economical. For example, long-term data collected from New York document that these insects reduce the density, height, and flower production of purple loosestrife, which in turn allows an increase in native plant diversity. This is the ultimate goal of weed management. Many biological control success stories are anecdotal, and purple loosestrife is one of the first examples for which we have strong evidence that control of invasive plants by insects can result in native plant recovery.
Identifying Integrated Pest Management Resource Needs Among Virginia Master Gardeners
Frank, Daniel; Blevins, Stephanie (Oxford University Press, 2024-07-20)
Two survey questionnaires distributed to Master Gardener (MG) volunteers in Virginia provide valuable insights into their awareness, understanding, and utilization of integrated pest management (IPM). Survey responses reveal a varied level of familiarity with IPM, with a notable percentage of respondents lacking knowledge of the term and differing perceptions of its focus on non-chemical or chemical pest control methods. While respondents generally recommended IPM solutions more than half the time, factors limiting their decision to do so included comfort level, limited understanding or knowledge, lack of training, lack of client interest, and lack of resources. The survey results highlight an agreement among respondents regarding the adequacy of state Cooperative Extension Service materials in addressing IPM. Pest management guides, websites, and fact sheets were the IPM resources most frequently used and perceived as effective. Respondents expressed a preference for fact sheets as the top resource material to enhance public training programs, followed by other multimedia content. Moreover, the survey results provide insights into the specific pest-related needs of Virginia MGs, revealing their priorities in terms of arthropod, vertebrate pest, plant disease, and weed resource topics. Overall, the data from the surveys offers a comprehensive understanding of MG perspectives on IPM, identifying areas for program improvement and providing guidance for the development of targeted resources to enhance MG knowledge and facilitate more effective public outreach.
New state records of Aculops ailanthi (Lin, Jin, and Kuang) (Acariformes: Trombidiformes: Prostigmata: Eriophyidae), in USA; a pest or biological control agent of Ailanthus altissima (Mill.) Swingle?
Bielski, Jason; Pfeiffer, Douglas G.; Ochoa, Ron; Brown, Alexander; Ulsamer, Andrew (Entomological Society of Washington, 2024-08-22)
We report the first detections of Aculops ailanthi Lin, Jin, and Kuang (1997) (Acariformes: Trombidiformes: Prostigmata: Eriophyidae) from Montgomery County, Virginia, and Wayne County, Michigan, USA; the fourth and fifth states to report this non-gall forming rust mite on Ailanthus altissima (Mill.) Swingle. We initially became aware of the pest in Virginia due to severe symptomology on greenhouse-cultivated Ai. altissima. In Michigan, similar observations from a field survey led to the mites' discovery. We tentatively identified the pest as an eriophyid mite of unknown species. Samples from both states were sent to USDA-ARS for identification and, using scanning electron microscopy, confirmed the species as A. ailanthi based on the morphological features. Moreover, we describe the impacts that high populations of A. ailanthi can have on Ai. altissima in greenhouse settings and potential use as a biological control agent. Field observations from Michigan are encouraging that A. ailanthi can affect Ai. altissima outside of greenhouse settings.
From ecological menace to roadside attraction: 28 years of evidence support successful biocontrol of purple loosestrife
Blossey, Bernd; Nuzzo, Victoria; Endriss, Stacy B. (Wiley, 2024-12-03)
Introduction and spread of non-native plants provide ecologists and evolutionary biologists with abundant scientific opportunities. However, land managers charged with preventing ecological impacts face financial and logistical challenges to reduce threats by introduced species. The available toolbox (chemical, mechanical, or biological) is also rather limited. Failure to permanently suppress introduced species by mechanical and chemical treatments may result in biocontrol programs using host-specific insect herbivores. Regardless of the chosen method, long-term assessment of management outcomes on both the target species and associated biota should be an essential component of management programs. However, data to assess whether management results in desirable outcomes beyond short-term reductions of the target plant are limited. Here, we use implementation of a biocontrol program targeting a widespread wetland invader, Lythrum salicaria (purple loosestrife), in North America to track outcomes on the target plant over more than two decades in New York State. After extensive testing, two leaf-feeding beetles (Galerucella calmariensis and Galerucella pusilla; hereafter “Galerucella”), a root-feeding weevil (Hylobius transversovittatus) and a flower-feeding weevil (Nanophyes marmoratus), were approved for field releases. We used a standardized monitoring protocol to record insect abundance and L. salicaria stem densities and heights in 1-m2 permanent quadrats at 33 different wetlands and followed sites for up to 28 years. As part of this long-term monitoring, in 20 of these wetlands, we established a factorial experiment releasing either no insects (control), only root feeders, only leaf beetles, or root and leaf feeders. We documented reduced L. salicaria occupancy and stem densities following insect releases over time, irrespective of site-specific differences in starting plant communities or L. salicaria abundance. We could not complete our factorial experiment because dispersal of leaf beetles to root-feeder-only and control sites within 5 years invalidated our experimental controls. Our data show that it took time for significant changes to occur, and short-term studies may provide misleading results, as L. salicaria stem densities initially increased before significantly decreasing. Several decades after insect releases, prerelease predictions of significant purple loosestrife declines have been confirmed.
Online toolkits for collaborative and inclusive global research in urban evolutionary ecology
Savage, Amy M.; Willmott, Meredith J.; Moreno-Garcia, Pablo; Jagiello, Zuzanna; Li, Daijiang; Malesis, Anna; Miles, Lindsay S.; Roman-Palacios, Cristian; Salazar-Valenzuela, David; Verrelli, Brian C.; Winchell, Kristin M.; Alberti, Marina; Bonilla-Bedoya, Santiago; Carlen, Elizabeth; Falvey, Cleo; Johnson, Lauren; Martin, Ella; Kuzyo, Hanna; Marzluff, John; Munshi-South, Jason; Phifer-Rixey, Megan; Stadnicki, Ignacy; Szulkin, Marta; Zhou, Yuyu; Gotanda, Kiyoko M. (Wiley, 2024-06-25)
Urban evolutionary ecology is inherently interdisciplinary. Moreover, it is a field with global significance. However, bringing researchers and resources together across fields and countries is challenging. Therefore, an online collaborative research hub, where common methods and best practices are shared among scientists from diverse geographic, ethnic, and career backgrounds would make research focused on urban evolutionary ecology more inclusive. Here, we describe a freely available online research hub for toolkits that facilitate global research in urban evolutionary ecology. We provide rationales and descriptions of toolkits for: (1) decolonizing urban evolutionary ecology; (2) identifying and fostering international collaborative partnerships; (3) common methods and freely-available datasets for trait mapping across cities; (4) common methods and freely-available datasets for cross-city evolutionary ecology experiments; and (5) best practices and freely available resources for public outreach and communication of research findings in urban evolutionary ecology. We outline how the toolkits can be accessed, archived, and modified over time in order to sustain long-term global research that will advance our understanding of urban evolutionary ecology.
Genomic Epidemiology of Rift Valley Fever Virus Involved in the 2018 and 2022 Outbreaks in Livestock in Rwanda
Nsengimana, Isidore; Juma, John; Roesel, Kristina; Gasana, Methode N.; Ndayisenga, Fabrice; Muvunyi, Claude M.; Hakizimana, Emmanuel; Hakizimana, Jean N.; Eastwood, Gillian; Chengula, Augustino A.; Bett, Bernard; Kasanga, Christopher J.; Oyola, Samuel O. (MDPI, 2024-07-17)
Rift Valley fever (RVF), a mosquito-borne transboundary zoonosis, was first confirmed in Rwanda’s livestock in 2012 and since then sporadic cases have been reported almost every year. In 2018, the country experienced its first large outbreak, which was followed by a second one in 2022. To determine the circulating virus lineages and their ancestral origin, two genome sequences from the 2018 outbreak, and thirty-six, forty-one, and thirty-eight sequences of small (S), medium (M), and large (L) genome segments, respectively, from the 2022 outbreak were generated. All of the samples from the 2022 outbreak were collected from slaughterhouses. Both maximum likelihood and Bayesian-based phylogenetic analyses were performed. The findings showed that RVF viruses belonging to a single lineage, C, were circulating during the two outbreaks, and shared a recent common ancestor with RVF viruses isolated in Uganda between 2016 and 2019, and were also linked to the 2006/2007 largest East Africa RVF outbreak reported in Kenya, Tanzania, and Somalia. Alongside the wild-type viruses, genetic evidence of the RVFV Clone 13 vaccine strain was found in slaughterhouse animals, demonstrating a possible occupational risk of exposure with unknown outcome for people working in meat-related industry. These results provide additional evidence of the ongoing wide spread of RVFV lineage C in Africa and emphasize the need for an effective national and international One Health-based collaborative approach in responding to RVF emergencies.
Hybridization between Aedes aegypti and Aedes mascarensis mosquitoes leads to disruption of male sex determination
Liang, Jiangtao; Kang, Lin; Michalak, Pawel; Sharakhov, Igor V. (Springer Nature, 2024-07-22)
Understanding the sex determination pathway and its disruptions in mosquitoes is critical for the effective control of disease vectors through genetic manipulations based on sex separation. When male hybrids of Aedes aegypti females and Ae. mascarensis males are backcrossed to Ae. aegypti females, a portion of the backcross progeny manifests as males with abnormal sexual differentiation. We discovered a significant correlation between pupal abnormalities and the feminization of subsequent adults exemplified by the relative abundance of ovarian and testicular tissues. All intersex individuals were genetic males as they expressed a male determining factor, Nix. Further, our analysis of the sex-specific splicing of doublesex and fruitless transcripts demonstrated the presence of both male and female splice variants indicating that sex determination is disrupted. A comparative transcriptomic analysis revealed similar expression levels of most female-associated genes in reproductive organs and carcasses between intersexual males and normal females. Moreover, intersexes had largely normal gene expression in testes but significant gene downregulation in male accessory glands when compared with normal males. We conclude that evolving hybrid incompatibilities between Ae. aegypti and Ae. mascarensis involve disruption of sex determination and are accompanied by changes in gene expression associated with sexual differentiation.
A naturally derived biomaterial formulation for improved menstrual care
Bataglioli, Rogerio Aparecido; Kaur, Harsimran; Muller, John; Geddes, Elizabeth; Champine, Carrie; Hsu, Bryan B. (Cell Press, 2024-07-10)
Adequately managing menstruation is an important factor in the overall quality of life for women. With a growing discussion of the global need for its improvement, it is clear that better management of menstruation can positively influence social, educational, and professional outcomes. Herein, we describe a biopolymer-based formulation that gels blood in a mechanism alternative to coagulation. We first tested several biopolymer mixtures with blood and quantified increases in viscosity, finding that high-molecular-weight alginate in combination with glycerol could rapidly absorb and gel blood. We then demonstrated that this powder could be deployed both as a traditional menstrual pad filler and as an additive to menstrual cups to reduce leakage and spillage, respectively. Finally, we include an antimicrobial polymer to impair the growth of Staphylococcus aureus, a bacterium associated with toxic shock syndrome. Collectively, our work describes a biodegradable formulation derived from renewable resources that can improve menstrual care.
Ecology and geography of Cache Valley virus assessed using ecological niche modeling
Muller, John A.; López, Krisangel; Escobar, Luis E.; Auguste, A. Jonathan (2024-06-26)
Background: Cache Valley virus (CVV) is an understudied Orthobunyavirus with a high spillover transmission potential due to its wide geographical distribution and large number of associated hosts and vectors. Although CVV is known to be widely distributed throughout North America, no studies have explored its geography or employed computational methods to explore the mammal and mosquito species likely participating in the CVV sylvatic cycle. Methods: We used a literature review and online databases to compile locality data for CVV and its potential vectors and hosts. We linked location data points with climatic data via ecological niche modeling to estimate the geographical range of CVV and hotspots of transmission risk. We used background similarity tests to identify likely CVV mosquito vectors and mammal hosts to detect ecological signals from CVV sylvatic transmission. Results: CVV distribution maps revealed a widespread potential viral occurrence throughout North America. Ecological niche models identified areas with climate, vectors, and hosts suitable to maintain CVV transmission. Our background similarity tests identified Aedes vexans, Culiseta inornata, and Culex tarsalis as the most likely vectors and Odocoileus virginianus (white-tailed deer) as the most likely host sustaining sylvatic transmission. Conclusions: CVV has a continental-level, widespread transmission potential. Large areas of North America have suitable climate, vectors, and hosts for CVV emergence, establishment, and spread. We identified geographical hotspots that have no confirmed CVV reports to date and, in view of CVV misdiagnosis or underreporting, can guide future surveillance to specific localities and species.
Free ride without raising a thumb: A citizen science project reveals the pattern of active ant hitchhiking on vehicles and its ecological implications
Hsu, Feng-Chuan; Hsu, Gen-Chang; Lee, Ching-Chen; Lin, Chung-Chi; Ho, Chuan-Kai; Yang, Chin-Cheng Scotty (Wiley, 2024-04)
1. Species hitchhiking on human transportation objects such as vehicles can facilitate long-distance dispersal of organisms, allowing increased probabilities of successful biological invasions. In Taiwan, there have been observations of ants actively moving onto motor vehicles (defined as ‘ant hitchhiking’ hereafter), yet no study has explored this phenomenon. 2. Here, we provide the first qualitative and quantitative report on ant hitchhiking behaviour using citizen science data. From 2017 to 2023, 52 cases of ant hitchhiking on vehicles were reported (at least three cases with queen[s] and another eight cases with brood), attributed to nine species. Seven of the nine species were exotic/invasive. Arboreal or semi-arboreal ant species, particularly the exotic black cocoa ant (Dolichoderus thoracicus), accounted for over half of the reported cases. The parking duration of the vehicles on which the ants hitchhiked ranged from several hours to over a month (30 cases occurred within a day). Moreover, more cases were reported in the warmer seasons (spring and summer) than in the colder seasons (fall and winter). 3. To our knowledge, this study represents the first effort to profile active ant hitchhiking on vehicles. We encourage future studies to examine the abiotic and biotic factors that determine the success of hitchhiking events to better predict the spread of exotic/invasive ants and to develop effective management strategies for preventing their biological invasions.
Influence of Fungicide Application on Rhizosphere Microbiota Structure and Microbial Secreted Enzymes in Diverse Cannabinoid-Rich Hemp Cultivars
Xu, Junhuan; Knight, Tyson; Boone, Donchel; Saleem, Muhammad; Finley, Sheree J.; Gauthier, Nicole; Ayariga, Joseph A.; Akinrinlola, Rufus; Pulkoski, Melissa; Britt, Kadie; Tolosa, Tigist; Rosado-Rivera, Yara I.; Iddrisu, Ibrahim; Thweatt, Ivy; Li, Ting; Zebelo, Simon; Burrack, Hannah; Thiessen, Lindsey; Hansen, Zachariah; Bernard, Ernest; Kuhar, Thomas; Samuel-Foo, Michelle; Ajayi, Olufemi S. (MDPI, 2024-05-28)
Microbes and enzymes play essential roles in soil and plant rhizosphere ecosystem functioning. However, fungicides and plant root secretions may impact the diversity and abundance of microbiota structure and enzymatic activities in the plant rhizosphere. In this study, we analyzed soil samples from the rhizosphere of four cannabinoid-rich hemp (Cannabis sativa) cultivars (Otto II, BaOx, Cherry Citrus, and Wife) subjected to three different treatments (natural infection, fungal inoculation, and fungicide treatment). DNA was extracted from the soil samples, 16S rDNA was sequenced, and data were analyzed for diversity and abundance among different fungicide treatments and hemp cultivars. Fungicide treatment significantly impacted the diversity and abundance of the hemp rhizosphere microbiota structure, and it substantially increased the abundance of the phyla Archaea and Rokubacteria. However, the abundances of the phyla Pseudomonadota and Gemmatimonadetes were substantially decreased in treatments with fungicides compared to those without fungicides in the four hemp cultivars. In addition, the diversity and abundance of the rhizosphere microbiota structure were influenced by hemp cultivars. The influence of Cherry Citrus on the diversity and abundance of the hemp rhizosphere microbiota structure was less compared to the other three hemp cultivars (Otto II, BaOx, and Wife). Moreover, fungicide treatment affected enzymatic activities in the hemp rhizosphere. The application of fungicides significantly decreased enzyme abundance in the rhizosphere of all four hemp cultivars. Enzymes such as dehydrogenase, dioxygenase, hydrolase, transferase, oxidase, carboxylase, and peptidase significantly decreased in all the four hemp rhizosphere treated with fungicides compared to those not treated. These enzymes may be involved in the function of metabolizing organic matter and degrading xenobiotics. The ecological significance of these findings lies in the recognition that fungicides impact enzymes, microbiota structure, and the overall ecosystem within the hemp rhizosphere.
Solving the 250-year-old mystery of the origin and global spread of the German cockroach, Blattella germanica
Tang, Qian; Vargo, Edward L.; Ahmad, Intan; Jiang, Hong; Varadínová, Zuzana Kotyková; Dovih, Pilot; Kim, Dongmin; Bourguignoni, Thomas; Booth, Warren; Schall, Coby; Mukha, Dmitry V.; Rheindt, Frank E.; Evans, Theodore A. (National Academy of Sciences, 2024-05-20)
The origin of the German cockroach, Blattella germanica, is enigmatic, in part because it is ubiquitous worldwide in human-built structures but absent from any natural habitats. The first historical records of this species are from ca. 250 years ago (ya) from central Europe (hence its name). However, recent research suggests that the center of diversity of the genus is Asian, where its closest relatives are found. To solve this paradox, we sampled genome-wide markers of 281 cockroaches from 17 countries across six continents. We confirm that B. germanica evolved from the Asian cockroach Blattella asahinai approximately 2,100 ya, probably by adapting to human settlements in India or Myanmar. Our genomic analyses reconstructed two primary global spread routes, one older, westward route to the Middle East coinciding with various Islamic dynasties (~1,200 ya), and another younger eastward route coinciding with the European colonial period (~390 ya). While Europe was not central to the early domestication and spread of the German cockroach, European advances in long-distance transportation and temperature-controlled housing were likely important for the more recent global spread, increasing chances of successful dispersal to and establishment in new regions. The global genetic structure of German cockroaches further supports our model, as it generally aligns with geopolitical boundaries, suggesting regional bridgehead populations established following the advent of international commerce.
Widespread Circulation of Tick-Borne Viruses in Virginia—Evidence of Exposure to Heartland, Bourbon, and Powassan Viruses in Wildlife and Livestock
Garba, Ahmed; Riley, Jennifer; Lahmers, Kevin K.; Eastwood, Gillian (MDPI, 2024-04-30)
Emerging tick-borne viruses such as Powassan virus (POWV), Bourbon virus (BRBV), and Heartland virus (HRTV), whilst rare, can cause severe health problems in humans. While limited clinical cases have been reported thus far in Virginia, the presence of tick-borne viruses poses a serious health threat, and the extent of their prevalence in Virginia is unknown. Here, we sought evidence of POWV, BRBV, and HRTV exposure in Virginia via a serological assessment of wildlife and livestock. Wildlife in Virginia were found to be seropositive against POWV (18%), BRBV (8%), and HRTV (5%), with western and northern regions of the state having a higher prevalence. Multiple wildlife species were shown to have been exposed to each virus examined. To a lesser extent, cattle also showed exposure to tick-borne viruses, with seroprevalences of 1%, 1.2%, and 8% detected in cattle against POWV, BRBV, and HRTV, respectively. Cross-reactivity against other known circulating mosquito-borne flaviviruses was ruled out. In conclusion, there is widespread exposure to tick-borne viruses in western and northern Virginia, with exposure to a diverse range of animal populations. Our study provides the first confirmation that HRTV is circulating in the Commonwealth. These findings strengthen the existing evidence of emerging tick-borne viruses in Virginia and highlight the need for public health vigilance to avoid tick bites.
Comparing Entomology-Themed Outreach Events: Annual Festivals and Open Houses in the United States
Wycoff, Stephanie Blevins; Frank, Daniel L.; Weaver, Michael J. (MDPI, 2024-05-07)
Over the past several decades, there has been a growing prevalence of entomology-themed outreach events, which seek to educate the public about insects and other arthropods, fostering a greater appreciation and understanding of these often misunderstood organisms. In 2016, a comparative analysis was initiated to identify science institutions across the United States engaged in providing annual entomology-themed outreach events to the public. Utilizing literature reviews and online searches, several science institutions were identified and subsequently contacted to partake in a survey regarding their events. The survey received a response rate of 93%. Results from the survey offered valuable insights into these entomology-themed outreach events, including records of attendance, event structures, funding sources, popular exhibits, and the impacts on attendees, hosting institutions, and local communities. While the majority of these events have remained in place since the survey, many have experienced significant disruptions due to the COVID-19 pandemic, prompting some to adapt to innovative online formats and virtual experiences. Despite these challenges, the commitment to entomological outreach continues today, highlighting the resilience and adaptability of the entomology community.
Two Nested Inversions in the X Chromosome Differentiate the Dominant Malaria Vectors in Europe, Anopheles atroparvus and Anopheles messeae
Soboleva, Evgenia S.; Kirilenko, Kirill M.; Fedorova, Valentina S.; Kokhanenko, Alina A.; Artemov, Gleb N.; Sharakhov, Igor V. (MDPI, 2024-04-26)
The Maculipennis subgroup of malaria mosquitoes includes both dominant malaria vectors and non-vectors in Eurasia. Understanding the genetic factors, particularly chromosomal inversions, that differentiate Anopheles species can provide valuable insights for vector control strategies. Although autosomal inversions between the species in this subgroup have been characterized based on the chromosomal banding patterns, the number and positions of rearrangements in the X chromosome remain unclear due to the divergent banding patterns. Here, we identified two large X chromosomal inversions, approximately 13 Mb and 10 Mb in size, using fluorescence in situ hybridization. The inversion breakpoint regions were mapped by hybridizing 53 gene markers with polytene chromosomes of An. messeae. The DNA probes were designed based on gene sequences from the annotated An. atroparvus genome. The two nested inversions resulted in five syntenic blocks. Only two small syntenic blocks, which encompass 181 annotated genes in the An. atroparvus genome, changed their position and orientation in the X chromosome. The analysis of the An. atroparvus genome revealed an enrichment of gene ontology terms associated with immune system and mating behavior in the rearranged syntenic blocks. Additionally, the enrichment of DNA transposons was found in sequences homologous to three of the four breakpoint regions. This study demonstrates the successful application of the physical genome mapping approach to identify rearrangements that differentiate species in insects with polytene chromosomes.
The probability of chromatin to be at the nuclear lamina has no systematic effect on its transcription level in fruit flies
Afanasyev, Alexander Y.; Kim, Yoonjin; Tolokh, Igor S.; Sharakhov, Igor V.; Onufriev, Alexey V. (2024-05-06)
Background: Multiple studies have demonstrated a negative correlation between gene expression and positioning of genes at the nuclear envelope (NE) lined by nuclear lamina, but the exact relationship remains unclear, especially in light of the highly stochastic, transient nature of the gene association with the NE. Results: In this paper, we ask whether there is a causal, systematic, genome-wide relationship between the expression levels of the groups of genes in topologically associating domains (TADs) of Drosophila nuclei and the probabilities of TADs to be found at the NE. To investigate the nature of this possible relationship, we combine a coarse-grained dynamic model of the entire Drosophila nucleus with genome-wide gene expression data; we analyze the TAD averaged transcription levels of genes against the probabilities of individual TADs to be in contact with the NE in the control and lamins-depleted nuclei. Our findings demonstrate that, within the statistical error margin, the stochastic positioning of Drosophila melanogaster TADs at the NE does not, by itself, systematically affect the mean level of gene expression in these TADs, while the expected negative correlation is confirmed. The correlation is weak and disappears completely for TADs not containing lamina-associated domains (LADs) or TADs containing LADs, considered separately. Verifiable hypotheses regarding the underlying mechanism for the presence of the correlation without causality are discussed. These include the possibility that the epigenetic marks and affinity to the NE of a TAD are determined by various non-mutually exclusive mechanisms and remain relatively stable during interphase. Conclusions: At the level of TADs, the probability of chromatin being in contact with the nuclear envelope has no systematic, causal effect on the transcription level in Drosophila. The conclusion is reached by combining model-derived time-evolution of TAD locations within the nucleus with their experimental gene expression levels.
RNAi-Mediated Silencing of Laccase 2 in Culex pipiens Pupae via Dehydration and Soaking Results in Multiple Defects in Cuticular Development
Naumenko, Anastasia N.; Fritz, Megan L. (MDPI, 2024-03-14)
Mosquitoes transmit a range of pathogens, causing devastating effects on human health. Population genetic control strategies have been developed and successfully used for several mosquito species. The most important step in identifying potential targets for mosquito control is the understanding of gene function. RNA interference (RNAi) is a powerful tool for gene silencing which has been widely used to study gene function in insects via knockdown of expression. The success of RNAi in insects depends on the efficient delivery of dsRNA into the cells, with microinjections being the most commonly used to study mosquito gene function. However, microinjections in the pupal stage lead to significant mortality in Aedes and Culex species, and few studies have performed microinjections in Culicinae pupae. Advanced techniques, such as CRISPR/Cas9 knockout, require establishing individual mosquito lines for each gene studied, and maintaining such lines may be limited by the insect-rearing capacity of a laboratory. Moreover, at times gene knockout during early development (embryo stage) has a deleterious effect on mosquito development, precluding the analysis of gene function in the pupal and adult stages and its potential for mosquito control. There is a need for a simple procedure that can be used for the fast and reliable examination of adult gene function via RNAi knockdown. Here, we focus on the aquatic stages of the mosquito life cycle and suggest a quick and easy assay for screening the functional role of genes in Culex pipiens mosquitoes without using microinjections. By dehydration of early stage pupae and subsequent rehydration in highly concentrated dsRNA, we achieved a moderate knockdown of laccase 2, a gene that turns on in the pupal stage and is responsible for melanization and sclerotization of the adult cuticle.
SARS-CoV-2 Specific Nanobodies Neutralize Different Variants of Concern and Reduce Virus Load in the Brain of h-ACE2 Transgenic Mice
Pavan, María Florencia; Bok, Marina; Betanzos San Juan, Rafael; Malito, Juan Pablo; Marcoppido, Gisela Ariana; Franco, Diego Rafael; Militelo, Daniela Ayelen; Schammas, Juan Manuel; Bari, Sara Elizabeth; Stone, William; López, Krisangel; Porier, Danielle LaBrie; Muller, John Anthony; Auguste, A. Jonathan; Yuan, Lijuan; Wigdorovitz, Andrés; Parreño, Viviana Gladys; Ibañez, Lorena Itat (MDPI, 2024-01-25)
Since the beginning of the COVID-19 pandemic, there has been a significant need to develop antivirals and vaccines to combat the disease. In this work, we developed llama-derived nanobodies (Nbs) directed against the receptor binding domain (RBD) and other domains of the Spike (S) protein of SARS-CoV-2. Most of the Nbs with neutralizing properties were directed to RBD and were able to block S-2P/ACE2 interaction. Three neutralizing Nbs recognized the N-terminal domain (NTD) of the S-2P protein. Intranasal administration of Nbs induced protection ranging from 40% to 80% after challenge with the WA1/2020 strain in k18-hACE2 transgenic mice. Interestingly, protection was associated with a significant reduction in virus replication in nasal turbinates and a reduction in virus load in the brain. Employing pseudovirus neutralization assays, we identified Nbs with neutralizing capacity against the Alpha, Beta, Delta, and Omicron variants, including a Nb capable of neutralizing all variants tested. Furthermore, cocktails of different Nbs performed better than individual Nbs at neutralizing two Omicron variants (B.1.529 and BA.2). Altogether, the data suggest the potential of SARS-CoV-2 specific Nbs for intranasal treatment of COVID-19 encephalitis.

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