Recombinant Encephalitozoon cuniculi Uncharacterized membrane protein ECU04_1080 (ECU04_1080)
Description
Introduction to Encephalitozoon cuniculi and ECU04_1080
Encephalitozoon cuniculi is a microsporidial unicellular parasite with worldwide distribution, classified as a parasitic fungus that infects various animal groups. It serves as a significant pathogen affecting mammals, particularly rabbits, in which it causes neurologic and renal disease . E. cuniculi can also cause disease in immunocompromised humans, making it a potential zoonotic pathogen of clinical importance .
The genome of E. cuniculi consists of approximately 2.9 megabases distributed across 11 chromosomes, encoding nearly 2,000 potential protein-coding genes . A striking feature of the E. cuniculi genome is the high proportion of uncharacterized proteins. According to the latest reference proteome, about 50% of its proteins remain functionally unassigned, including approximately 620 proteins annotated as "uncharacterized" .
ECU04_1080 is one such uncharacterized membrane protein encoded in the E. cuniculi genome. The designation "ECU04_1080" represents its ordered locus name in the genomic sequence, where "ECU04" refers to the genomic location and "1080" is the specific identifier within that region .
Physical and Chemical Properties
While comprehensive biochemical characterization data is limited, commercial product specifications provide some insight into the physical properties of the recombinant form of ECU04_1080. The recombinant protein is typically supplied as a lyophilized powder with purity greater than 90% as determined by SDS-PAGE analysis .
Expression Systems and Methodology
The recombinant production of ECU04_1080 utilizes bacterial expression systems, specifically Escherichia coli, for heterologous expression . The full-length protein (amino acids 1-112) is typically fused to an N-terminal histidine tag to facilitate purification through affinity chromatography .
Challenges in Membrane Protein Expression
The recombinant expression of membrane proteins, including ECU04_1080, presents unique challenges compared to soluble proteins. Over the past several decades, numerous reports have highlighted the variability in expression levels among membrane proteins, with some accumulating to high levels while others, even closely related ones, are barely detected .
Recent studies have provided insights into host cell responses to membrane protein expression and the mechanisms of membrane insertion. Successful overproduction of membrane proteins is often linked to the avoidance of stress responses in the host cell . Research has identified genes that are either upregulated or downregulated when yields of membrane-inserted proteins are poor, suggesting complex cellular adaptations during expression .
Understanding the role of the translocon, which mediates protein translocation and membrane insertion, has been a focus of research to determine how protein segments are integrated into membranes . These insights may inform strategies for improving the recombinant expression of challenging membrane proteins like ECU04_1080.
Reconstitution Protocol
The recommended reconstitution protocol involves dissolving the lyophilized protein in deionized sterile water to achieve a concentration between 0.1-1.0 mg/mL . Addition of glycerol (typically to a final concentration of 50%) is advised for long-term storage stability . Suppliers note that repeated freezing and thawing should be avoided to maintain protein integrity.
ELISA and Immunological Applications
Recombinant ECU04_1080 is available in formats suitable for enzyme-linked immunosorbent assay (ELISA) applications . These preparations may be utilized in developing serological tests for detecting antibodies against E. cuniculi in research or diagnostic settings, though specific validated protocols are not detailed in the available literature.
Current Research Status
Despite its commercial availability, published research specifically focused on ECU04_1080's function appears limited. This protein remains part of the considerable proportion of E. cuniculi's proteome that lacks functional characterization, reflecting broader challenges in microsporidian research .
The uncharacterized status of ECU04_1080 should be considered in the context of E. cuniculi as a model organism for microsporidian biology. The compact genome of E. cuniculi, characterized by reduced intergenic spacers and shortened proteins relative to eukaryotic orthologs, represents an evolutionary adaptation to parasitism . Studying proteins like ECU04_1080 may provide insights into microsporidian-specific adaptations and host-parasite interactions.
Relationship to E. cuniculi Pathogenesis
E. cuniculi infection manifests differently based on host immunity, with immunocompetent individuals often exhibiting mild or subclinical disease, while immunocompromised hosts may develop severe clinical signs . The parasite primarily affects the central nervous system, kidneys, and eyes in rabbits, causing conditions ranging from vestibular disease and paralysis to renal insufficiency and ocular inflammation .
While the specific contribution of ECU04_1080 to E. cuniculi's pathogenic mechanisms remains unknown, its classification as a membrane protein suggests potential roles in host-parasite interactions, environmental sensing, or nutrient acquisition - functions critical for obligate intracellular parasites .
Diagnostic Relevance
Diagnosis of E. cuniculi infection typically relies on serological testing for antibodies, histopathological examination of affected tissues, or molecular detection methods such as PCR . The role of specific proteins like ECU04_1080 in diagnostic applications remains largely unexplored, though recombinant proteins can potentially serve as antigens in diagnostic immunoassays.
Functional Characterization
The uncharacterized status of ECU04_1080 presents opportunities for future research focused on elucidating its biological function. Potential approaches might include:
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Localization studies using fluorescently tagged versions of the protein
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Interaction studies to identify binding partners
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Gene knockout or silencing experiments to assess phenotypic effects
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Structural analyses to determine three-dimensional configuration
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Expression studies to identify conditions that regulate its production
Therapeutic and Preventive Applications
Understanding the function of ECU04_1080 and similar uncharacterized proteins could potentially inform the development of novel therapeutic strategies against microsporidian infections. If ECU04_1080 proves essential for parasite survival or virulence, it might represent a target for antiparasitic interventions.
Product Specs
Note: We will prioritize shipping the format currently in stock. However, if you have a specific format requirement, please indicate it in your order notes. We will fulfill your request whenever possible.
Note: Our proteins are shipped with standard blue ice packs. If you require dry ice shipping, please inform us in advance. Additional fees will apply.
Generally, the shelf life of liquid form is 6 months at -20°C/-80°C. For lyophilized form, the shelf life is 12 months at -20°C/-80°C.
Target Background
KEGG: ecu:ECU04_1080
Q&A
What is ECU04_1080 protein and what is its structural composition?
ECU04_1080 is an uncharacterized membrane protein from Encephalitozoon cuniculi with 112 amino acids. The full amino acid sequence is: MAESVASSESLPQMKPEEPESKKSPSREAIPKDMPVVNVRDIMMYVENMEGMENKKLIPY VVYLDEQFKEIVQKRRKDARVVFIFMIAIMSMLVIGLVVCGVKLLGYLMEQK . This relatively small protein is likely a transmembrane protein based on its sequence characteristics, though its specific function remains undetermined. The protein has been successfully expressed as a recombinant protein with an N-terminal His-tag in E. coli expression systems, facilitating its purification and subsequent experimental applications .
How does ECU04_1080 relate to other proteins in Encephalitozoon cuniculi?
While the specific interactions of ECU04_1080 with other proteins in E. cuniculi are not fully characterized, its classification as a membrane protein suggests potential roles in cellular processes such as signal transduction, transport, or host-parasite interactions. The available search results do not indicate specific pathway associations or protein-protein interactions for ECU04_1080 . This gap represents an important research opportunity for scientists working with this organism. Comparative analyses with homologous proteins in related microsporidian species may provide insights into conserved functions and evolutionary relationships.
What are the optimal conditions for expression and purification of recombinant ECU04_1080?
The recombinant ECU04_1080 protein has been successfully expressed in E. coli with an N-terminal His-tag . For optimal storage and handling, the following conditions are recommended:
| Parameter | Recommended Condition |
|---|---|
| Storage temperature | -20°C/-80°C |
| Storage form | Lyophilized powder |
| Storage buffer | Tris/PBS-based buffer, 6% Trehalose, pH 8.0 |
| Reconstitution | Deionized sterile water to 0.1-1.0 mg/mL |
| Long-term storage | Add 5-50% glycerol (final concentration) and aliquot |
For reconstitution, it is recommended to briefly centrifuge the vial prior to opening and to avoid repeated freeze-thaw cycles . The purified protein demonstrates greater than 90% purity as determined by SDS-PAGE, making it suitable for various research applications .
What technical challenges might researchers face when working with membrane proteins like ECU04_1080?
Working with membrane proteins presents several methodological challenges that researchers should anticipate:
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Solubility issues: Membrane proteins often form inclusion bodies during expression, potentially necessitating optimization of expression conditions or refolding protocols.
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Maintaining native conformation: The protein's structure depends on the lipid environment, making appropriate detergent selection critical during purification.
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Functional assays: Developing meaningful functional assays for an uncharacterized protein requires careful experimental design and appropriate controls.
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Structural characterization: Membrane proteins present unique challenges for structural determination techniques like crystallography or NMR.
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Stability concerns: ECU04_1080, like many membrane proteins, may demonstrate reduced stability when removed from its native membrane environment, requiring careful buffer optimization .
How can recombinant ECU04_1080 be utilized in Encephalitozoon cuniculi research?
Recombinant ECU04_1080 can serve as a valuable tool for multiple research applications:
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Antibody Development: The purified protein can be used to generate specific antibodies for immunolocalization studies, allowing researchers to determine the protein's distribution in infected tissues.
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Protein-Protein Interaction Studies: The His-tagged protein facilitates pull-down assays and other interaction studies to identify binding partners.
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Functional Characterization: In vitro assays can test hypothesized functions based on sequence or structural predictions.
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Vaccination Studies: As a potential antigen, ECU04_1080 could be evaluated for its ability to elicit protective immune responses in animal models.
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Structural Studies: The purified protein can be subjected to structural determination techniques to elucidate its three-dimensional configuration .
What role might ECU04_1080 play in Encephalitozoon cuniculi pathogenesis?
As a membrane protein, ECU04_1080 may contribute to E. cuniculi pathogenesis through several potential mechanisms:
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Host Cell Invasion: Membrane proteins often participate in the invasion process that microsporidia use to inject their sporoplasm into host cells.
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Immune Evasion: Surface-exposed membrane proteins can modulate host immune responses, potentially contributing to persistent infection.
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Intracellular Survival: The protein may help establish or maintain the parasite's intracellular niche within host cells.
Understanding these potential roles requires experimental verification through techniques such as gene knockout/knockdown (if feasible), neutralization with specific antibodies, or heterologous expression systems .
Could ECU04_1080 serve as a diagnostic marker for Encephalitozoon cuniculi infections?
The potential utility of ECU04_1080 as a diagnostic marker remains to be fully explored. Current diagnostic methods for E. cuniculi infections primarily rely on serological detection of antibodies against the parasite, with IgM and IgG antibodies serving as indicators of infection status . In a study conducted in Slovenia from 2017 to 2021, 65.6% of tested pet rabbits were seropositive for E. cuniculi antibodies .
For ECU04_1080 to serve as an effective diagnostic marker, researchers would need to:
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Determine if the protein elicits a specific antibody response in infected hosts
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Evaluate the protein's expression levels during different infection stages
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Develop sensitive and specific detection methods targeting either the protein itself or host antibodies against it
How does the immune response to Encephalitozoon cuniculi relate to potential ECU04_1080 research?
The immune response to E. cuniculi involves both humoral and cell-mediated components. Studies have shown that CD4+ and CD8+ T lymphocytes play crucial protective roles following oral ingestion of the pathogen. Research by Jeklova et al. demonstrated that CD4+ T lymphocyte proliferation predominates early in infection (2 weeks post-infection), while CD8+ T lymphocyte proliferation becomes more significant later (6-8 weeks post-infection) .
For ECU04_1080 research, understanding these immune dynamics is important because:
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As a membrane protein, ECU04_1080 may be exposed to the host immune system
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It could potentially serve as a target for antibody or T-cell responses
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Understanding host-pathogen interactions may inform therapeutic or vaccine development
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Immune-related studies could help elucidate the protein's role in pathogenesis
What bioinformatic approaches can help predict functions of uncharacterized proteins like ECU04_1080?
For uncharacterized proteins like ECU04_1080, several bioinformatic approaches can provide functional insights:
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Sequence Homology Analysis: Identifying distant homologs through sensitive alignment tools like PSI-BLAST or HMM-based methods.
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Structural Prediction: Using tools like AlphaFold2 to predict protein structure, which may reveal functional domains not evident from sequence alone.
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Transmembrane Domain Prediction: Applying specialized algorithms to identify membrane-spanning regions and topology.
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Protein Domain Analysis: Identifying conserved domains that might suggest specific biochemical functions.
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Evolutionary Analysis: Examining conservation patterns across related species to identify functionally important regions.
These computational approaches should guide experimental design rather than replace empirical testing of protein function.
How can researchers address the challenge of functional annotation for ECU04_1080?
Functional annotation of ECU04_1080 represents a significant challenge requiring a multi-faceted approach:
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Genomic Context Analysis: Examining neighboring genes may provide clues about functional relationships.
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Transcriptomic Profiling: Determining when the gene is expressed during the parasite life cycle can suggest specific biological roles.
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Proteomic Analysis: Identifying post-translational modifications and interaction partners.
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Heterologous Expression Systems: Testing hypothesized functions in well-characterized model organisms.
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CRISPR-Based Approaches: If feasible, gene disruption or modification can reveal phenotypic consequences.
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Comparative Analysis: Studying the protein in context with other microsporidian species may reveal conserved functions .
How does Encephalitozoon cuniculi infection manifest in host organisms?
E. cuniculi infection in rabbits (encephalitozoonosis) presents with various clinical manifestations depending on which organ systems are affected. Based on a study of 224 pet rabbits in Slovenia, the following patterns were observed:
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Neurological Signs: The most common presentation in seropositive rabbits, including head tilt, ataxia, and paralysis.
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Gastrointestinal Disorders: Including recurrent hypomotility, chronic weight loss, cachexia, and anorexia.
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Urinary System Complications: Distended urinary bladder, dysuria, incontinence, and sludgy urine, likely resulting from neurological defects.
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Ocular Manifestations: Phacoclastic uveitis, which is less common but characteristic.
Importantly, approximately 25% of seropositive rabbits presented without clinical signs, suggesting asymptomatic carriers play a role in transmission .
What histopathological findings characterize Encephalitozoon cuniculi infections?
Histopathological examination remains one of the most reliable diagnostic approaches for E. cuniculi infection. Key findings include:
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Brain Lesions: Granulomatous meningoencephalitis with perivascular cuffs composed of plasma cells, lymphocytes, and macrophages. Multifocal gliosis, glial nodules, and neuronal degeneration are also observed.
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Kidney Abnormalities: Chronic interstitial nephritis with fibrosis indicated by capsule adherence to the parenchyma.
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Ocular Changes: Focal uveitis in the anterior chamber, lens opacity, and possible increased corneal thickness.
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Parasite Detection: Mature E. cuniculi spores can be identified within parasitophorous vacuoles in the cytoplasm of perivascular macrophages and neurons. Extracellular spores are visible throughout the cerebral cortex and hippocampus .
