Recombinant Bat coronavirus HKU3 Nucleoprotein2 (N) is produced through a baculovirus expression system, yielding the complete protein spanning amino acids 1 to 421. The protein includes a C-terminal 6xHis-tag, which makes purification and detection more straightforward. SDS-PAGE analysis shows purity levels exceeding 85%, making this recombinant protein well-suited for research applications that demand high-quality reagents.
The nucleoprotein of Bat coronavirus HKU3 appears to play a central role in how the virus replicates and assembles itself. It's involved in packaging and protecting viral RNA—essentially making it a key player in coronavirus biology research. Studying its function may provide valuable insights into how these viruses cause disease and could help researchers develop better diagnostic tools and treatments.
Potential Applications
Note: The applications listed below are based on what we know about this protein's biological functions, published research, and experience from experts in the field. However, we haven't fully tested all of these applications ourselves yet. We'd recommend running some preliminary tests first to make sure they work for your specific research goals.
The protein is expressed in a baculovirus system (eukaryotic, supporting complex protein folding and some post-translational modifications), which significantly increases the likelihood of proper folding compared to prokaryotic systems. Full-length expression (1-421 aa) preserves all functional domains, and the C-terminal 6xHis tag minimizes structural disruption. However, no experimental validation of folding (e.g., by circular dichroism spectroscopy, thermal shift assays) or bioactivity (e.g., RNA-binding capability, oligomerization) is provided. While the baculovirus system is favorable, the protein's correct folding and functional state remain probable but unconfirmed.
1. Comparative Coronavirus Nucleoprotein Structure-Function Studies
This full-length recombinant nucleoprotein is suitable for comparative studies, but conclusions about evolutionary relationships and conserved structural patterns require confirmation of its native conformation. Comparative analyses of binding strengths and oligomerization states with nucleoproteins from other coronaviruses (e.g., SARS-CoV-2) should be interpreted with caution unless this protein's folding is first validated against a known standard.
2. RNA-Protein Interaction Screening Assays
This protein can be used in RNA-binding experiments (e.g., EMSA), but its RNA-binding affinity and specificity are unproven. Results from such assays will only be biologically relevant if the protein is correctly folded. The His-tag facilitates immobilization for pull-down assays, but binding kinetics data should be considered preliminary without functional validation.
3. Antibody Development and Immunological Characterization
This protein is a valid immunogen for generating antibodies targeting BtCoV HKU3. However, antibody specificity must be confirmed using a native antigen source (e.g., from infected cells), as antibodies raised against this recombinant version might not recognize the authentically folded nucleoprotein in a viral context. Its utility in immunoassays like immunofluorescence for tracking protein localization is high only if correct folding is confirmed.
4. Protein-Protein Interaction Studies
Pull-down assays using this protein can identify potential interaction partners. However, any interactions discovered must be verified to be physiologically relevant. Misfolding, even if unlikely in this system, could lead to false positives/negatives. The baculovirus system supports proper folding for interactions, but the identified host or viral protein partners require confirmation via orthogonal methods.
5. Biochemical Assay Development and Optimization
This protein can serve as a standardized reagent for assay development. However, assays designed to screen for inhibitors of "nucleoprotein function" (e.g., RNA-binding) are only valid if the protein's bioactivity is first demonstrated. The consistency offered by the His-tag is valuable for quantification, but the assay's biological relevance hinges on using a functionally active protein.
Final Recommendation & Action Plan
This baculovirus-expressed, full-length BtCoV HKU3 nucleoprotein is a promising reagent for the proposed applications due to the favorable expression system. However, a critical first step is to validate its structural integrity and bioactivity: perform circular dichroism spectroscopy to confirm secondary structure, a thermal shift assay to assess stability, and an RNA-binding assay (e.g., EMSA) to verify function. Once native-like folding and activity are confirmed, the protein can be reliably used for comparative studies, interaction mapping, and antibody generation. If validation fails, reconsider the expression or purification strategy. For all applications, especially those measuring kinetic parameters or making functional conclusions, using this protein as a well-characterized standard will significantly enhance the reliability and biological relevance of the findings.
