Recombinant Human MECOM Protein: Handling & Application Protocol
Recombinant Human MECOM Protein: Handling & Application Protocol
Recombinant Human MECOM Protein is a research-grade transcriptional regulator used in studies of hematopoiesis, myeloid malignancy, and oncogenic signaling pathways.
- Product Name
- Recombinant Human MECOM Protein
- SKU
- rp369521
- Protein Function
- Transcriptional regulator involved in hematopoiesis and oncogenesis (EVI1/MDS1-EVI1 locus)
- Primary Research Areas
- Hematopoiesis, myeloid leukemia, transcription factor biology
- Recommended Storage
- -80°C for long-term storage; avoid repeated freeze-thaw cycles
- Supplier
- Aladdin Scientific (absea#PP-4989)
Background and Biological Significance of MECOM
MECOM (MDS1 and EVI1 Complex Locus) encodes a family of transcription factors that play critical roles in hematopoietic stem cell maintenance, embryonic development, and oncogenesis. The locus produces multiple isoforms, including EVI1 and MDS1-EVI1 (also known as PR-domain-containing EVI1), which differ in their N-terminal domains and functional properties.
Overexpression or rearrangement of MECOM, particularly the EVI1 isoform, is strongly associated with aggressive myeloid malignancies, including acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS). EVI1 functions as a transcriptional repressor and activator depending on context, interacting with co-regulators such as GATA factors, Smad proteins, and histone deacetylases (HDACs).
Recombinant Human MECOM Protein (rp369521) enables researchers to study these molecular interactions in cell-free biochemical assays, protein–protein interaction studies, and structural investigations without relying on endogenous expression systems.
Reconstitution and Storage Instructions
Reconstitution: Prior to use, briefly centrifuge the vial to collect lyophilized material at the bottom. Reconstitute the protein in sterile, deionized water or the recommended buffer (typically PBS, pH 7.4, supplemented with a carrier protein such as 0.1% BSA) to a stock concentration as specified on the product datasheet. Gently pipette to mix; do not vortex, as shear force may denature the protein.
Working Concentration: Optimal working concentrations depend on the specific assay format. Titration is strongly recommended for each experimental application. Typical starting concentrations for biochemical binding assays range from 0.1 to 10 µg/mL; however, users should verify empirically for their specific system.
Storage: Aliquot reconstituted protein into single-use volumes to minimize freeze-thaw cycles. Store aliquots at -80°C for long-term use, or at -20°C for short-term use (up to 1 month). Avoid storing at 4°C for extended periods, as protein degradation may occur. Do not refreeze thawed aliquots.
Carrier Protein: Addition of 0.1% BSA (bovine serum albumin) or equivalent stabilizing agent is recommended when working at low protein concentrations to prevent adsorption to tube surfaces and maintain activity.
Quality Control and Verification
Purity Assessment: Verify protein purity by SDS-PAGE under reducing and non-reducing conditions. A single predominant band at the expected molecular weight indicates satisfactory purity. The specific molecular weight of MECOM isoforms varies; consult the product datasheet for the expressed construct's predicted mass.
Functional Verification: Where applicable, confirm biological activity using an appropriate biochemical or cell-based assay. For transcription factor proteins such as MECOM, electrophoretic mobility shift assay (EMSA) or fluorescence polarization assay can be employed to confirm DNA-binding activity to known MECOM consensus sequences.
Endotoxin Testing: For cell-based applications, verify that endotoxin levels meet acceptable thresholds (typically <1.0 EU/µg) as specified on the certificate of analysis (CoA). High endotoxin levels can confound results in cell culture experiments.
Protein Concentration: Confirm concentration by BCA or Bradford assay after reconstitution, as slight variations may occur between lots. Record the confirmed concentration before proceeding with experiments.
Recommended Applications and Experimental Considerations
Recombinant Human MECOM Protein is suitable for a range of in vitro research applications. The following guidance applies to common use cases:
- Protein–Protein Interaction (PPI) Studies: MECOM interacts with multiple co-regulators in the context of hematopoiesis and leukemia. Use pull-down assays, co-immunoprecipitation with recombinant partners, or surface plasmon resonance (SPR) to characterize these interactions. Ensure buffer compatibility between binding partners.
- DNA-Binding Assays (EMSA / FP): MECOM contains zinc finger domains that mediate sequence-specific DNA binding. Prepare labeled or fluorescent oligonucleotide probes containing consensus MECOM-binding sequences. Include appropriate positive and negative controls, as well as competitor unlabeled DNA for specificity confirmation.
- Antibody Validation: Recombinant MECOM protein may serve as a positive control antigen for validating anti-MECOM antibodies in ELISA or Western blot formats.
- Structural Studies: High-purity recombinant protein is suitable as a reference standard or component for cryo-EM or X-ray crystallography studies, subject to achieving sufficient concentration and homogeneity.
Important Note: MECOM contains multiple zinc finger motifs; inclusion of zinc (ZnCl₂, typically 10–50 µM) in assay buffers is recommended to maintain structural integrity of the zinc finger domains. Avoid metal chelators such as EDTA in working buffers unless specifically required by the assay design.
Troubleshooting Guide
The following table summarizes common issues encountered when working with Recombinant Human MECOM Protein and recommended corrective actions:
- Protein Aggregation: May result from improper reconstitution, high concentration, or freeze-thaw damage. Centrifuge at 10,000 × g for 10 minutes at 4°C before use; consider adding a non-ionic detergent (e.g., 0.01% Tween-20) or increasing BSA concentration in the diluent buffer.
- Low or No Activity in Binding Assay: Confirm zinc supplementation in the assay buffer. Verify that the DNA probe sequence corresponds to a validated MECOM consensus motif. Check protein integrity by SDS-PAGE. Ensure the protein has not been exposed to repeated freeze-thaw cycles.
- Non-specific Bands on Western Blot: Optimize primary antibody concentration; include recombinant protein as a molecular weight marker/positive control to confirm expected band position. Ensure denaturing conditions are appropriate for the isoform of interest.
- High Background in ELISA: Reduce coating concentration; optimize blocking conditions (1–5% BSA or non-fat milk); ensure thorough washing steps between incubations.
- Rapid Protein Degradation: Ensure protease inhibitor cocktail is included in all working buffers. Maintain cold chain during handling; work on ice at all times.
Frequently asked questions
What is the biological function of MECOM, and why is it relevant in cancer research?
MECOM encodes transcription factor isoforms (including EVI1) that regulate hematopoietic stem cell self-renewal and differentiation. Overexpression or chromosomal rearrangement of MECOM, particularly EVI1, is a hallmark of poor-prognosis acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS), making it a critical target for mechanistic and therapeutic research.
How should I reconstitute Recombinant Human MECOM Protein (rp369521) for first use?
Briefly centrifuge the vial to collect lyophilized material, then reconstitute in sterile PBS (pH 7.4) supplemented with 0.1% BSA to the concentration indicated on the datasheet. Mix by gentle pipetting—do not vortex. Aliquot immediately into single-use volumes and store at -80°C to avoid repeated freeze-thaw cycles.
Why is zinc supplementation important when working with MECOM protein?
MECOM contains multiple zinc finger domains that are essential for its DNA-binding and protein-interaction functions. Zinc ions (Zn²⁺) are required cofactors that stabilize the tertiary structure of these domains. Omission of zinc from assay buffers or inclusion of metal chelators such as EDTA can disrupt zinc finger folding, resulting in loss of DNA-binding activity and unreliable experimental results.
Is Recombinant Human MECOM Protein suitable for use in cell-based assays?
Recombinant MECOM protein is primarily intended for in vitro biochemical applications such as binding assays, PPI studies, and antibody validation. For cell-based applications, ensure endotoxin levels are below the threshold specified on the CoA (typically <1.0 EU/µg). Consult the product datasheet for specific guidance on cell-compatible formulations and concentrations.
How can I confirm that the reconstituted MECOM protein is functionally active?
Functional activity of MECOM protein can be confirmed by electrophoretic mobility shift assay (EMSA) or fluorescence polarization (FP) assay using oligonucleotide probes containing validated MECOM DNA-binding consensus sequences. SDS-PAGE under reducing conditions should also be performed to confirm purity and expected molecular weight before proceeding with functional assays.
References
- Gröschel S, et al. A single oncogenic enhancer rearrangement causes concomitant EVI1 and GATA2 deregulation in leukemia. Cell. 2014;157(2):369-381. doi:10.1016/j.cell.2014.02.019
- Lugthart S, et al. Clinical, molecular, and prognostic significance of WHO type inv(3)(q21q26.2)/t(3;3)(q21;q26.2) and various other 3q abnormalities in acute myeloid leukemia. J Clin Oncol. 2010;28(24):3890-3898. doi:10.1200/JCO.2010.29.2771
- Goyama S, Mulloy JC. Molecular pathogenesis of core binding factor leukemia: current knowledge and future prospects. Int J Hematol. 2011;94(2):126-133. doi:10.1007/s12185-011-0858-z
Products are supplied for research and development use only. Not for use in humans, animals, diagnosis, or therapy.
