Recombinant Epstein-Barr virus Epstein-Barr nuclear antigen 3 (EBNA3) is expressed in E. coli and comprises amino acids 1-138. The protein comes with an N-terminal 10xHis tag and a C-terminal Myc tag, which makes purification and detection more straightforward. It reaches a purity of over 85%, as verified by SDS-PAGE. This product is intended for research use only and is not for use in diagnostic or therapeutic applications.
EBNA3 is a nuclear antigen from the Epstein-Barr virus that appears to play a crucial role in regulating viral and cellular gene expression. It seems to be involved in modulating host cell processes and likely contributes to the virus's ability to establish latency. Research involving EBNA3 may be essential for understanding Epstein-Barr virus pathogenesis and the mechanisms underlying viral persistence and oncogenic transformation.
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.
Based on the provided information, the recombinant EBNA3 fragment is expressed in E. coli, a prokaryotic system that is fundamentally unsuitable for producing functional eukaryotic viral proteins like EBNA3. EBNA3 is a complex nuclear antigen that requires precise folding, nuclear localization, and specific post-translational modifications for its transcriptional regulatory functions. The expressed fragment (1-138aa) represents only a small N-terminal portion of the full-length protein and contains dual tags (N-terminal 10xHis and C-terminal Myc) that may interfere with proper folding. E. coli lacks the eukaryotic chaperones and modification machinery necessary for the correct folding of this viral protein. Since activity is unverified and the expression system is mismatched for this complex eukaryotic protein, the protein is highly likely to be misfolded and inactive without experimental validation.
1. Antibody Development and Validation
The recombinant EBNA3 fragment can serve as an effective immunogen for generating antibodies that recognize linear epitopes within the 1-138aa region, even if the EBNA3 protein is misfolded. The dual tags facilitate purification and detection. However, antibodies may not recognize conformational or modification-dependent epitopes of full-length, properly folded EBNA3 in infected cells. Validation against native EBNA3 from EBV-infected cells is essential.
2. Protein-Protein Interaction Studies
This application is high-risk without folding validation. While the His-tag enables technical feasibility for pull-down assays, if the EBNA3 fragment is misfolded (as expected in E. coli), it will not interact physiologically with true binding partners. The fragment represents only a small portion of the full protein and may lack complete functional domains. Identified interactions are likely to be non-physiological artifacts. This application should not be pursued without confirmation of proper folding.
3. ELISA-Based Binding Assays
This application should be approached with caution. If the EBNA3 fragment is misfolded, binding assays will not reflect biological reality. The tags enable technical development of ELISA formats, but results may be misleading without proper folding validation. This application requires prior demonstration of proper folding and specific binding capability.
4. Biochemical Characterization Studies
This application is well-suited for assessing the recombinant EBNA3 protein itself. Techniques like size-exclusion chromatography and circular dichroism spectroscopy can evaluate the protein's physical properties. However, these studies characterize the E. coli-expressed EBNA3 fragment and may not reflect the behavior of native, full-length EBNA3.
Final Recommendation & Action Plan
Given the high probability of misfolding in E. coli for this complex viral protein fragment, we recommend first performing biophysical characterization (circular dichroism for secondary structure, size-exclusion chromatography for oligomeric state) to assess folding quality. Antibody development can proceed as the safest application. Avoid all functional studies (interactions, binding assays) until proper folding is validated. For reliable EBNA3 research, obtain full-length protein from eukaryotic expression systems capable of proper folding and post-translational modifications. Always validate findings with native EBNA3 from EBV-infected cells when possible.
