CSN7 Antibody
Description
Overview of CSN7 Antibody
The CSN7 antibody specifically recognizes the CSN7 subunit, which exists in two paralogs: CSN7A and CSN7B. These subunits are integral to the CSN complex, which interacts with cullin-RING ubiquitin ligases (CRLs) to regulate protein ubiquitination and degradation .
Research Applications
CSN7 antibodies are primarily used to:
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Differentiate CSN7A and CSN7B isoforms in cellular studies .
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Investigate the structural and functional roles of CSN7 in CRL-mediated proteasomal degradation .
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Study adipogenic differentiation and cellular stress responses .
Isoform-Specific Functions
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CSN7A: Downregulation slows adipogenesis, suggesting a role in maintaining baseline differentiation processes .
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CSN7B: Overexpression accelerates adipogenesis and associates with increased CSN complex activity during differentiation. This isoform preferentially binds β-TrCP and USP15, indicating distinct regulatory roles compared to CSN7A .
Antibody Specificity
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Anti-CSN7A and anti-CSN7B antibodies show no cross-reactivity, enabling precise detection of each isoform in Western blotting and immunoprecipitation .
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Flag-tagged CSN7A/B pulldowns confirmed isoform-specific interactions within the CSN complex (Table 1) .
Table 1: CSN7 Antibody Characteristics
| Parameter | CSN7A Antibody | CSN7B Antibody |
|---|---|---|
| Target Epitope | C-terminal region of CSN7A | C-terminal region of CSN7B |
| Host Species | Rabbit | Rabbit |
| Applications | WB, IP, IF | WB, IP, IF |
| Observed MW | ~45 kDa (predicted: 45 kDa) | ~45 kDa (predicted: 45 kDa) |
| Key Partners | Cul1, Cul3, USP15 | β-TrCP, USP15 |
Mechanistic Insights
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CSN7B overexpression enhances deneddylation activity, promoting CRL substrate receptor exchange and sustaining ubiquitin ligase function .
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CSN7A knockdown disrupts CRL-CSN interactions, leading to impaired proteasomal degradation and cell cycle dysregulation .
Technical Validation
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Western Blot: Anti-CSN7A/B antibodies detect endogenous and overexpressed isoforms in LiSa-2 cells, with ~20–30% expression efficiency compared to endogenous levels .
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Density Gradient Centrifugation: Confirmed integration of Flag-CSN7A/B into native CSN complexes, validating antibody specificity .
Implications for Disease Research
While not directly linked to therapeutics, CSN7 antibodies are vital tools for studying:
Product Specs
Constituents: 50% Glycerol, 0.01M PBS, pH 7.4
Target Background
- CSN acts as a negative regulator of ribonucleotide reductase (RNR) activity in Arabidopsis. PMID: 21614643
- CSN7 contains a PCI motif, which plays a role in the assembly of the COP9 signalosome. PMID: 18854373
Q&A
Experimental Design for CSN7 Antibody Studies
Q: How should I design experiments to study the role of CSN7 antibodies in cellular processes? A: When designing experiments to study CSN7 antibodies, consider using techniques like Western blotting and immunohistochemistry to assess protein expression and localization. For advanced studies, incorporate methods such as co-immunoprecipitation to explore interactions with other proteins within the COP9 signalosome complex . Ensure controls are included to validate antibody specificity.
Data Interpretation and Contradiction Analysis
Q: How do I analyze and resolve contradictions in data when using CSN7 antibodies across different experimental setups? A: Analyze data by comparing results from multiple techniques (e.g., Western blot vs. immunofluorescence) to validate findings. Contradictions may arise from differences in antibody specificity, sample preparation, or experimental conditions. Use statistical methods to assess variability and ensure that results are reproducible across different setups.
Antibody Specificity and Validation
Q: What methods can I use to validate the specificity of CSN7 antibodies? A: Validate antibody specificity by using blocking peptides, comparing results with different antibodies targeting the same protein, and assessing reactivity in knockout cell lines if available. Techniques like Western blotting can help confirm the expected molecular weight of the target protein .
Advanced Applications in Research
Q: How can CSN7 antibodies be used in advanced research applications, such as studying protein interactions or signaling pathways? A: Use CSN7 antibodies in co-immunoprecipitation assays to study interactions with other proteins within the COP9 signalosome complex. Additionally, employ techniques like proximity ligation assays (PLA) to visualize protein-protein interactions in situ. These methods can provide insights into the role of CSN7 in cellular signaling pathways .
Troubleshooting Common Issues
Q: What are common issues encountered when using CSN7 antibodies, and how can they be resolved? A: Common issues include non-specific binding or low signal intensity. Resolve these by optimizing antibody concentrations, using appropriate blocking agents, and ensuring proper antigen retrieval for immunohistochemistry. Also, consider using different antibody clones or isotypes to improve specificity and signal strength .
Comparative Analysis of Different CSN7 Antibodies
Q: How do I compare the performance of different CSN7 antibodies for my research? A: Compare antibodies by evaluating their specificity, sensitivity, and reactivity across various applications (e.g., Western blot, IHC). Use tables to organize data on antibody characteristics such as isotype, immunogen, and reactive species. This helps in selecting the most suitable antibody for specific research needs.
Example Comparison Table:
