Microsporidian Infection Research Articles

Molecular Survey of Microsporidia, Blastocystis, Cryptosporidium and Giardia in Pet Avian Species in Tehran, Iran

Background: Opportunistic microorganisms of the intestinal tract, such as Cryptosporidium spp. Giardia spp. Blastocystis sp. and microsporidia, are increasingly responsible for clinical disorders in various host species, including humans. Objectives: This study was conducted to search for the above parasites in the feces of pet birds using parasitological and molecular methods in Tehran City, Iran. Methods: In the current study, fecal samples of avian birds were collected and investigated with modified Ziehl-Neelsen, modified trichrome, and trichrome staining for the presence of microsporidia, Cryptosporidium, Blastocystis and Giardia. All the samples were examined molecularly with specific primers and PCR methods. Results: Three of the examined droppings contained Encephalitozoon hellem genotype 1B (2%) by PCR and sequencing. The microsporidian organisms were recovered from the droppings of a clinically normal green-cheek parakeet, an African gray parrot, and a lovebird. Other parasites that were examined were not found in the analyzed samples. Conclusion: The current study proved that captive pet birds are a possible source of microsporidian infection. Besides the fact that encephalitozoonosis is predominantly subclinical in birds, the highly resistant nature of the microsporidia spores can put the owners at increased risk of disease acquisition via spore inhalation or ingestion.

Microsporidian EnP1 alters host cell H2B monoubiquitination and prevents ferroptosis facilitating microsporidia survival

Microsporidia are intracellular eukaryotic pathogens that pose a substantial threat to immunocompromised hosts. The way these pathogens manipulate host cells during infection remains poorly understood. Using a proximity biotinylation strategy we established that microsporidian EnP1 is a nucleus-targeted effector that modifies the host cell environment. EnP1's translocation to the host nucleus is meditated by nuclear localization signals (NLSs). In the nucleus, EnP1 interacts with host histone H2B. This interaction disrupts H2B monoubiquitination (H2Bub), subsequently impacting p53 expression. Crucially, this inhibition of p53 weakens its control over the downstream target gene SLC7A11, enhancing the host cell's resilience against ferroptosis during microsporidian infection. This favorable condition promotes the proliferation of microsporidia within the host cell. These findings shed light on the molecular mechanisms by which microsporidia modify their host cells to facilitate their survival.

Translocator protein (TSPO) inhibits Nosema bombycis proliferation in silkworm, Bombyx mori.

Pebrine disease, caused by Nosema bombycis (Nb) infection in silkworms, is a severe and long-standing disease that threatens sericulture. As parasitic pathogens, a complex relationship exists between microsporidia and their hosts at the mitochondrial level. Previous studies have found that the translocator protein (TSPO) is involved in various biological functions, such as membrane potential regulation, mitochondrial autophagy, immune responses, calcium ion channel regulation, and cell apoptosis. In the present study, we found that TSPO expression in silkworms (BmTSPO) was upregulated following Nb infection, leading to an increase in cytoplasmic calcium, adenosine triphosphate, and reactive oxygen species levels. Knockdown and overexpression of BmTSPO resulted in the promotion and inhibition of Nb proliferation, respectively. We also demonstrated that the overexpression of BmTSPO promotes host cell apoptosis and significantly increases the expression of genes involved in the immune deficiency and Janus kinase-signal transducer and the activator of the transcription pathways. These findings suggest that BmTSPO activates the innate immune signalling pathway in silkworms to regulate Nb proliferation. Targeting TSPO represents a promising approach for the development of new treatments for microsporidian infections.

Tick-borne microsporidiosis: ticks as a neglected source of human microsporidian infections?

ABSTRACT We detected 24 Encephalitozoon cuniculi positive Ixodes ricinus ticks of 284 collected in the Czech Republic. Since the route of transmission of microsporidia is not fully understood, the presence of microsporidia in ticks raises the question of whether they may be involved in the transmission of these pathogens.

Mass mortality event of round sardinella Sardinella aurita Valenciennes associated with Glugea Thélohan, 1891 microsporidian infection off the southern Italian coast.

Intracellular parasites of the genus Glugea Thélohan, 1891 (Microsporidia) comprise about 34 putative species capable of causing high morbidity and mortality in freshwater and marine teleost fishes. In this study, we report on the first mass mortality event associated with Glugea sp. infecting free-ranging round sardinella Sardinella aurita in the southern Tyrrhenian Sea (Italy). Here, we describe the ultrastructure of mature spores of this microsporidian and characterize it molecularly, as well as report its phylogenetic position. Most of the affected fish showed an irregular swelling of its abdomen. At necropsy, a variable number of xenomas, spherical to ellipsoidal in shape, were found in the peritoneal cavity strongly attached to the viscera of all fish. Histological analysis revealed varying severity of chronic inflammation along with occasional necrosis in visceral organs associated with multiple xenoma proliferation. These pathological findings were considered the main cause of this mass mortality event. Morphologically, the present material was closely related to G. sardinellesis and G. thunni. The phylogenetically closest taxa to the newly SSU rDNA sequence were G. thunni and an erroneusly identified G. plecoglossi, which were very closely related to each other, also suggesting that all these sequences might belong to the same species.

Detection of Enterocytozoon bieneusi in Non-Human Primates in Portuguese Zoos.

Enterocytozoon bieneusi, an intracellular eukaryote closely related to fungi, is recognized as a significant pathogen affecting humans, particularly those with compromised immune systems. While its transmission routes are still not fully elucidated, fecal-oral transmission remains the primary one. With a wide host range, the zoonotic potential of E. bieneusi is a concern, albeit direct evidence of animal-to-human transmission remains scarce. Genotyping based on the internal transcribed spacer (ITS) region facilitates the delineation of genetic diversity, with potentially zoonotic genotypes predominantly associated with Groups 1 and 2. Despite the broad spectrum of susceptible animal hosts, research into microsporidian infection among zoo animals remains limited. This study aimed to evaluate the occurrence of E. bieneusi infection across diverse captive animals, focusing on zoo settings in Portugal. Fecal samples were collected from a variety of animals, and molecular detection of E. bieneusi was conducted using nested PCR targeting the ITS region. Of 127 fecal samples, 1.57% (95% CI: 0.19-5.57) tested positive for E. bieneusi, with non-human primates (NHP's) exhibiting an 18.18% (95% CI: 2.28-51.78) occurrence. Phylogenetic analysis revealed clustering within Group 2 genotypes, indicating potential zoonotic implications. This study highlights the need for further research to understand the epidemiology of E. bieneusi in zoo environments and its potential transmission pathways to humans.

Endochitinase from the Microsporidia Nosema ceranae facilitates infection in the honey bee Apis mellifera

Bees are crucial pollinators in terrestrial ecosystems, responsible for 80% of insect-driven pollination and playing a vital role in the pollination of 75% of crops. The honey bee, Apis mellifera, is not only used in honey production but also serves as a pollinator in agriculture. However, A. mellifera faces various challenges, including exposure to pathogens such as the Microsporidia Nosema ceranae, which has been linked to decreased crop yields and colony losses. Nosema ceranae spores infect adult honey bees by penetrating the midgut lumen and invading the cytoplasm of epithelial cells, completing their life cycle. However, the midgut possesses a protective mechanical barrier called the peritrophic matrix, composed of chitin and proteins, which prevents epithelial infection. Nevertheless, N. ceranae overcomes this primary defense mechanism, though the specific mechanisms it employs to cross the peritrophic matrix and reach the midgut epithelium are not yet well understood. This study aimed to investigate the potential role of the predicted endochitinase from N. ceranae to infect bees. We tested the hypothesis that inhibiting the expression of N. ceranae endochitinase through RNA interference would impact the pathogen infection of A. mellifera. Bees treated with dsRNA targeting endochitinase, administered 12 and 24 h after spore inoculation, exhibited suppressed endochitinase gene expression and a decrease in the number of total and viable N. ceranae spores in the midgut. These results indicate that inhibiting the expression of the target gene through RNA interference affects Microsporidia infection, underscoring the importance of this enzyme in the infection process.

Endoparasite Infections in Captive Inland Bearded Dragons (Pogona vitticeps) in Italy.

The inland bearded dragon (Pogona vitticeps) is a lizard species commonly kept as a pet worldwide. Endoparasites are among the most important pathogens affecting bearded dragons. The aim of this study was to evaluate the endoparasites in captive P. vitticeps in Italy. Faecal samples from 30 P. vitticeps were analysed by fresh faecal smears, flotation tests, the Mini-FLOTAC technique, and a rapid immunoassay to detect Cryptosporidium spp. To search for microsporidia, PCR and sequencing were performed on the faecal samples. Data were statistically analysed. The overall positivity rate for endoparasites was 83.3% (25/30). The identified endoparasites were oxyurids (17/30, 56.7%), Isosospora amphiboluri (13/30, 43.3%), Encephalitozoon pogonae (4/18, 22.22%), and Cryptosporidium sp. (1/30, 3.33%). The positivity for protozoa was significantly higher in juveniles compared to adults. Moreover, the frequency of clinical signs was significantly higher in the positive animals. The results obtained here emphasize the importance of regular veterinary examinations of captive P. vitticeps, aimed at the diagnosis, treatment, and control of endoparasites. This study is one of the largest surveys on microsporidia infections in living bearded dragons, suggesting that E. pogonae may be widespread in this lizard.

Microsporidian heavy infection in a batch of salted and dried cod.

The aim of this work is the description and characterization of a severe microsporidian infection in a batch of salted and dried cod. Particularly, the case involves a batch of approximately 800 kg obtained from Gadus macrocephalus (Food and Agriculture Organization Zone 61 - Northwest Pacific Ocean), which, after rehydration and sectioning operations, underwent routine company checks before packaging. In about 20% of the samples, the presence of whitish nodules with a diameter ranging from 1 to 2 mm was observed on the surface of the fillets and in cross-section. The lesions ranged from a few units to 10 per cm2. Some samples were subjected to fresh microscopic observation with the stereomicroscope, confirming the nodular nature of the lesions, which were often confluent, alternating with empty spaces, giving the tissue a honeycombing aspect. The histological examination at low magnification allowed us to observe the heavy vacuolization of nodular lesions irregularly surrounded by a spongy-like wall. The observation at higher magnification of other sections allowed us to identify intra-myofibrillar cists containing presumptive microsporidian elements. The tissue damage derived from the technological processes and gravity of lesions did not allow a morphological characterization of presumptive protozoans. The molecular examination of the nodular lesions and the analysis of the sequence of an 897 bp fragment of the small subunit 16S rRNA revealed 100% identity with Microsporidium theragrae (GenBank accession number MT928885-89) first isolated from the skeletal muscles of Gadus chalcogrammus specimens from the Sea of Okhotsk. This finding confirms the importance of selecting suppliers and raw materials in the seafood industry, as well as the usefulness of an effective traceability system.

Isolation and Identification of Nematode-Infecting Microsporidia.

Nematodes are naturally infected by the fungal-related pathogen microsporidia. These ubiquitous eukaryotic parasites are poorly understood, despite infecting most types of animals. Identifying novel species of microsporidia and studying them in an animal model can expedite our understanding of their infection biology and evolution. Nematodes present an excellent avenue for pursuing such work, as they are abundant in the environment and many species are easily culturable in the laboratory. The protocols presented here describe how to isolate bacterivorous nematodes from rotting substrates, screen them for microsporidia infection, and molecularly identify the nematode and microsporidia species. Additionally, we detail how to remove environmental contaminants and generate a spore preparation of microsporidia from infected samples. We also discuss potential pitfalls and provide suggestions on how to mitigate them. These protocols allow for the identification of novel microsporidia species, which can serve as an excellent starting point for genomic analysis, determination of host specificity, and infection characterization. © 2024 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Gathering samples Support Protocol 1: Generating 10× and 40× Escherichia coli OP50 and seeding NGM plates Basic Protocol 2: Microsporidia screening, testing for Caenorhabditis elegans susceptibility, and sample freezing Basic Protocol 3: DNA extraction, PCR amplification, and sequencing to identify nematode and microsporidia species Basic Protocol 4: Removal of contaminating microbes and preparation of microsporidia spores Support Protocol 2: Bleach-synchronizing nematodes.

Identification of long non-coding RNAs in response to microsporidia infection in Silkworm, Bombyx mori.

Microsporidia Nosema bombycis (Nb) is a cellular parasite responsible for pébrine disease in silkworms, significantly impacting the sericulture industry. Long non-coding RNAs (lncRNAs), which are RNA fragments longer than 200 nucleotides, are pivotal in a range of cellular and physiological functions. However, the potential role of silkworm lncRNAs in response to Nb infection remains unknown. This study conducted transcriptome sequencing on both larvae and Nb-infected midguts of silkworms, identifying 1,440 lncRNAs across all examined midgut samples. Within the Nb-infected group, 42 differentially expressed lncRNAs (DElncRNAs) and 305 differentially expressed mRNAs (DEmRNAs) were detected. Functional annotation and pathway analysis showed that these DEmRNAs are mostly involved in metabolism, apoptosis, autophagy, and other key pathways. The co-expression network of DEmRNAs and DElncRNAs illustrates that 1 gene could be regulated by multiple lncRNAs and 1 lncRNA may target multiple genes, indicating that the regulation of lncRNA is intricate and networked. In addition, the DElncRNA-miRNA-mRNA network showed that some DElncRNAs may be involved in the immune response and metabolism through miRNA. Notably, the study observed an increase in lncRNA MSTRG857.1 following Nb infection, which may promote Nb proliferation. These findings offer insights into the complex interplay between insects and microsporidia.

Proteasome inhibition triggers tissue-specific immune responses against different pathogens in C. elegans.

Protein quality control pathways play important roles in resistance against pathogen infection. For example, the conserved transcription factor SKN-1/NRF up-regulates proteostasis capacity after blockade of the proteasome and also promotes resistance against bacterial infection in the nematode Caenorhabditis elegans. SKN-1/NRF has 3 isoforms, and the SKN-1A/NRF1 isoform, in particular, regulates proteasomal gene expression upon proteasome dysfunction as part of a conserved bounce-back response. We report here that, in contrast to the previously reported role of SKN-1 in promoting resistance against bacterial infection, loss-of-function mutants in skn-1a and its activating enzymes ddi-1 and png-1 show constitutive expression of immune response programs against natural eukaryotic pathogens of C. elegans. These programs are the oomycete recognition response (ORR), which promotes resistance against oomycetes that infect through the epidermis, and the intracellular pathogen response (IPR), which promotes resistance against intestine-infecting microsporidia. Consequently, skn-1a mutants show increased resistance to both oomycete and microsporidia infections. We also report that almost all ORR/IPR genes induced in common between these programs are regulated by the proteasome and interestingly, specific ORR/IPR genes can be induced in distinct tissues depending on the exact trigger. Furthermore, we show that increasing proteasome function significantly reduces oomycete-mediated induction of multiple ORR markers. Altogether, our findings demonstrate that proteasome regulation keeps innate immune responses in check in a tissue-specific manner against natural eukaryotic pathogens of the C. elegans epidermis and intestine.

Ultrastructural insights into the microsporidian infection apparatus reveal the kinetics and morphological transitions of polar tube and cargo during host cell invasion.

During host cell invasion, microsporidian spores translocate their entire cytoplasmic content through a thin, hollow superstructure known as the polar tube. To achieve this, the polar tube transitions from a compact spring-like state inside the environmental spore to a long needle-like tube capable of long-range sporoplasm delivery. The unique mechanical properties of the building blocks of the polar tube allow for an explosive transition from compact to extended state and support the rapid cargo translocation process. The molecular and structural factors enabling this ultrafast process and the structural changes during cargo delivery are unknown. Here, we employ light microscopy and in situ cryo-electron tomography to visualize multiple ultrastructural states of the Vairimorpha necatrix polar tube, allowing us to evaluate the kinetics of its germination and characterize the underlying morphological transitions. We describe a cargo-filled state with a unique ordered arrangement of microsporidian ribosomes, which cluster along the thin tube wall, and an empty post-translocation state with a reduced diameter but a thicker wall. Together with a proteomic analysis of endogenously affinity-purified polar tubes, our work provides comprehensive data on the infection apparatus of microsporidia and uncovers new aspects of ribosome regulation and transport.

Energetics of the microsporidian polar tube invasion machinery

Microsporidia are eukaryotic, obligate intracellular parasites that infect a wide range of hosts, leading to health and economic burdens worldwide. Microsporidia use an unusual invasion organelle called the polar tube (PT), which is ejected from a dormant spore at ultra-fast speeds, to infect host cells. The mechanics of PT ejection are impressive. Anncaliia algerae microsporidia spores (3–4 μm in size) shoot out a 100-nm-wide PT at a speed of 300 μm/s, creating a shear rate of 3000 s-1. The infectious cargo, which contains two nuclei, is shot through this narrow tube for a distance of ∼60–140 μm (Jaroenlak et al, 2020) and into the host cell. Considering the large hydraulic resistance in an extremely thin tube and the low-Reynolds-number nature of the process, it is not known how microsporidia can achieve this ultrafast event. In this study, we use Serial Block-Face Scanning Electron Microscopy to capture 3-dimensional snapshots of A. algerae spores in different states of the PT ejection process. Grounded in these data, we propose a theoretical framework starting with a systematic exploration of possible topological connectivity amongst organelles, and assess the energy requirements of the resulting models. We perform PT firing experiments in media of varying viscosity, and use the results to rank our proposed hypotheses based on their predicted energy requirement. We also present a possible mechanism for cargo translocation, and quantitatively compare our predictions to experimental observations. Our study provides a comprehensive biophysical analysis of the energy dissipation of microsporidian infection process and demonstrates the extreme limits of cellular hydraulics.

Energetics of the microsporidian polar tube invasion machinery.

Microsporidia are eukaryotic, obligate intracellular parasites that infect a wide range of hosts, leading to health and economic burdens worldwide. Microsporidia use an unusual invasion organelle called the polar tube (PT), which is ejected from a dormant spore at ultra-fast speeds, to infect host cells. The mechanics of PT ejection are impressive. Anncaliia algerae microsporidia spores (3-4 μm in size) shoot out a 100-nm-wide PT at a speed of 300 μm/s, creating a shear rate of 3000 s-1. The infectious cargo, which contains two nuclei, is shot through this narrow tube for a distance of ∼60-140 μm (Jaroenlak et al, 2020) and into the host cell. Considering the large hydraulic resistance in an extremely thin tube and the low-Reynolds-number nature of the process, it is not known how microsporidia can achieve this ultrafast event. In this study, we use Serial Block-Face Scanning Electron Microscopy to capture 3-dimensional snapshots of A. algerae spores in different states of the PT ejection process. Grounded in these data, we propose a theoretical framework starting with a systematic exploration of possible topological connectivity amongst organelles, and assess the energy requirements of the resulting models. We perform PT firing experiments in media of varying viscosity, and use the results to rank our proposed hypotheses based on their predicted energy requirement. We also present a possible mechanism for cargo translocation, and quantitatively compare our predictions to experimental observations. Our study provides a comprehensive biophysical analysis of the energy dissipation of microsporidian infection process and demonstrates the extreme limits of cellular hydraulics.

Independent and interactive effects of diet and entomopathogenic microsporidia on an outbreaking forest insect defoliator

Abstract Insect herbivore diet mediates interactions with entomopathogens, yet this is relatively unexplored for microsporidia. Here, we examine a diet‐mediated tri‐trophic interaction between an outbreaking forest defoliator, forest tent caterpillar (FTC) Malacosoma disstria Hübner and Nosema sp. microsporidia. We conducted two experiments where diet quality was manipulated by incorporating lyophilized aspen (Populus tremuloides Michaux) foliage into an artificial diet, which was compared to a standard artificial diet. Diet quantity varied between fully fed and partially starved conditions, simulating an outbreak scenario. Microsporidia infection occurred naturally or was induced via experimental inoculation. We assessed FTC survival, microsporidia infection and load, and sublethal effects of treatments on FTC traits. Plant secondary metabolite concentrations in aspen‐augmented diets varied between experiments. In Experiment 1, the aspen‐augmented diet contained lyophilized aspen foliage with low concentrations of secondary metabolites, which increased FTC survival and reduced microsporidia infection. Diet quality and infection load also interactively influenced adult wing traits in Experiment 1. In Experiment 2, the aspen‐augmented diet contained lyophilized aspen foliage with higher concentrations of secondary metabolites, which negatively affected FTC. No diet‐mediated interactions with microsporidia were observed in Experiment 2. Diet quality (Experiments 1 and 2), diet quantity (Experiment 2) and microsporidia infection (Experiments 1 and 2) directly influenced FTC survival and/or had sublethal effects on FTC that may have cascading effects on population dynamics and dispersal. We demonstrated that diet quality can mediate interactions between FTC and microsporidia, but these interactions depend on the defensive chemistry of the FTC diet. To our knowledge, this is the first study to report diet‐mediated interactions between an outbreaking forest pest and microsporidia and one of only a few studies to examine this tri‐trophic interaction among Lepidoptera.

Study of microsporidians in white faecal syndrome affected farmed shrimp (Penaeus vannamei) Boone, 1931 of West Bengal, India

Enterocytozoon hepatopenaei (EHP), an intracellular microsporidian parasite, has been reported in cultivated Penaeus vannamei infected with white faecal syndrome (WFS) in south-east Asian shrimp producing countries. The appearance of white faecal strings floating on the surface of the ponds indicates a severe microsporidian infection. In the present study suspected shrimps and floating faecal strings were collected from culture ponds of study area located in Purba Medinipur district of West Bengal. This study aims to unveil the presence of microsporidians in hepatopancreas and associated histopathological changes in it using light and scanning electron microscopy, and microsporidian identification by nested PCR. Microscopic study revealed the presence of oval-shaped microsporidian spores in the hepatopancreas and nested PCR study confirmed that these spores belong to E. hepatopenaei. The spores isolated from the floating faecal strings exhibited similar morphology with those found in hepatopancreas. Histopathology of the hepatopancreas of WFS-affected shrimp exhibited alterations in hepatopancreatic tissues along with haemocytic infiltration into the inter-tubular spaces and evidence of necrosis, vacuolation and degeneration. The findings from the nested PCR analysis indicated a total of 18 positive results (69.23%) out of 26 samples studied. WFS infection can be considered a gastrointestinal disorder caused by severe EHP infection, which is significant in the grow-out ponds in the regions under study.

Microsporidia dressing up: the spore polaroplast transport through the polar tube and transformation into the sporoplasm membrane.

Microsporidia are obligate intracellular parasites that infect a wide variety of hosts including humans. Microsporidian spores possess a unique, highly specialized invasion apparatus involving the polar filament, polaroplast, and posterior vacuole. During spore germination, the polar filament is discharged out of the spore forming a hollow polar tube that transports the sporoplasm components including the nucleus into the host cell. Due to the complicated topological changes occurring in this process, the details of sporoplasm formation are not clear. Our data suggest that the limiting membrane of the nascent sporoplasm is formed by the polaroplast after microsporidian germination. Using electron microscopy and 1,1'-dioctadecyl-3,3,3',3' tetramethyl indocarbocyanine perchlorate staining, we describe that a large number of vesicles, nucleus, and other cytoplasm contents were transported out via the polar tube during spore germination, while the posterior vacuole and plasma membrane finally remained in the empty spore coat. Two Nosema bombycis sporoplasm surface proteins (NbTMP1 and NoboABCG1.1) were also found to localize in the region of the polaroplast and posterior vacuole in mature spores and in the discharged polar tube, which suggested that the polaroplast during transport through the polar tube became the limiting membrane of the sporoplasm. The analysis results of Golgi-tracker green and Golgi marker protein syntaxin 6 were also consistent with the model of the transported polaroplast derived from Golgi transformed into the nascent sporoplasm membrane.IMPORTANCEMicrosporidia, which are obligate intracellular pathogenic organisms, cause huge economic losses in agriculture and even threaten human health. The key to successful infection by the microsporidia is their unique invasion apparatus which includes the polar filament, polaroplast, and posterior vacuole. When the mature spore is activated to geminate, the polar filament uncoils and undergoes a rapid transition into the hollow polar tube that transports the sporoplasm components including the microsporidian nucleus into host cells. Details of the structural difference between the polar filament and polar tube, the process of cargo transport in extruded polar tube, and the formation of the sporoplasm membrane are still poorly understood. Herein, we verify that the polar filament evaginates to form the polar tube, which serves as a conduit for transporting the nucleus and other sporoplasm components. Furthermore, our results indicate that the transported polaroplast transforms into the sporoplasm membrane during spore germination. Our study provides new insights into the cargo transportation process of the polar tube and origin of the sporoplasm membrane, which provide important clarification of the microsporidian infection mechanism.

PALS-14 promotes resistance to Nematocida parisii infection in Caenorhabditis elegans.

Microsporidia are common natural pathogens of the nematode Caenorhabditis elegans . Infection of C. elegans by the microsporidian species Nematocida parisii leads to induction of the Intracellular Pathogen Response (IPR), including transcriptional upregulation of 26 pals genes. The divergent ' pals ' sequence signature is conserved with humans, but PALS proteins have unknown biochemical functions. So far, none of the 26 induced pals genes have a demonstrated role in immunity. Here, we use RNAseq data, RNA interference, and CRISPR/Cas9 mutant analysis to identify the N. parisii -induced pals-14 gene as an immune gene that provides defense against microsporidia infection in C. elegans .

Avrupa Yaban Arısı Vespula vulgaris Linnaeus, 1758 (Hymenoptera: Vespidae)'in Türkiye'de Microsporidian Patojeni Kaydı

Microsporidia are common enigmatic pathogens of hymenopterans. Although these species are more concerned with Apidae (especially honeybees), they are also known to infect members of Vespidae. Apart from these species, many defined and undefined microsporidia infections were detected infecting Vespidae individuals in the literature. Especially Vespula vulgaris Linnaeus, 1758 (Hymenoptera: Vespidae) infected different microsporidian species like a Nosema bombi, Vavraia culicis, Nosema vespula, etc. Molecular identification-based microsporidian records in predator species such as V. vulgaris are highly suspicious. In such predator insects, microsporidian infections should be supported by characteristic visuals of the pathogen’s life cycle. With this perspective this study is the first and only study that presents the life-cycle stages and spore morphometrics data of a microsporidium isolated from V. vulgaris. V. vulgaris samples were collected from July to September 2021 in Trabzon, Turkey. During the observations, 415 samples were examined, and five of them were infection positive (microsporidiosis prevalence 1.20%). Infection was found mostly in the midgut of the host, and infection was mostly chronic. Fresh mature spores were oval in shape and measured 4.57±0.54 (3.26–5.95; n=200) µm in length and 2.43±0.33 (1.43–3.35; n=200) µm in width. The current microsporidium has a Nosema-like disporoblastic merogony and sporogony.