Mass Spectrometry Analysis to Identify Ubiquitylation of EYFP-tagged CENP-A (EYFP-CENP-A)
June 10th, 2020
CENP-A ubiquitylation is an important requirement for CENP-A deposition at the centromere, inherited through dimerization between cell division, and indispensable to cell viability. Here we describe mass spectrometry analysis to identify ubiquitylation of EYFP-tagged CENP-A (EYFP-CENP-A) protein.
Overview
This study investigates the role of CENP-A ubiquitylation in its deposition at the centromere, a process crucial for cell viability. Using mass spectrometry, the researchers identify the ubiquitylation sites on EYFP-tagged CENP-A, particularly focusing on the K124R mutant, to understand its biological significance.
Key Study Components
Research Area
- Cell biology
- Genetics
Background
- CENP-A is vital for centromere function and cell viability.
- Ubiquitylation affects protein stability and localization.
Methods Used
- Mass spectrometry analysis
- Immunoprecipitation of EYFP-CENP-A
- Protein A beads bound with anti-GFP antibody
Main Results
- Identification of ubiquitylation sites on EYFP-CENP-A, especially lysine 306.
- Both EYFP-CENP-A wild type and K124R mutant showed similar properties in centromere localization.
- Ubiquitylation is essential for proper protein function at the centromere.
Conclusions
- The study demonstrates the critical role of CENP-A ubiquitylation in centromere assembly.
- Findings enhance understanding of cellular mechanisms essential for viability and gene regulation.
Frequently Asked Questions
Executive Industry Relevance
Mass spectrometry-based identification of ubiquitylation sites on centromere proteins such as EYFP-tagged CENP-A enables precise mapping of post-translational modifications critical for chromosome segregation fidelity. This workflow supports mechanistic de-risking in early discovery by clarifying how protein tagging or mutation may alter ubiquitylation patterns, directly impacting target validation and predictive confidence for chromosomal instability models. The approach is broadly applicable to centromere-kinetochore protein studies, informing translational research on genome stability and cancer progression.
Strategic Applications in Biopharma R&D
Early Discovery & Target Validation
- Enables interrogation of ubiquitylation's role in centromere identity and function.
- Supports biological de-risking by revealing tag-induced modification shifts in target proteins.
- Facilitates functional target validation for proteins implicated in chromosomal instability.
Screening & Assay Development
- Prepares validated protein constructs for downstream post-translational modification analysis.
- Standardizes immunoprecipitation and mass spectrometry workflows for reproducible detection of ubiquitylation.
- Generates quantitative site-specific modification data to inform assay development.
Translational & Preclinical Research
- Aligns with disease-relevant models of chromosomal instability and cancer biology.
- Enables continuity from molecular discovery to preclinical validation of centromere-targeted interventions.
- Provides mechanistic insights that support risk-adjusted advancement decisions in genome stability programs.
Pipeline & Workflow Integration
This mass spectrometry workflow integrates from early discovery through preclinical research, supporting both hypothesis testing and translational continuity for centromere-associated targets.
- Discovery Biology: Clarifies the impact of protein tagging and mutation on ubiquitylation, supporting mechanistic hypothesis testing.
- Screening: Delivers reproducible, quantitative readouts of site-specific ubiquitylation for assay standardization.
- Analytics: Provides high-resolution mass spectrometry data for comparative analysis of protein modifications.
- Translational Research: Connects molecular findings to disease-relevant models of chromosomal instability.
- Enterprise Reuse: Offers a broadly applicable workflow for post-translational modification mapping across protein targets.
Operational & Enterprise Impact
- Scientific Value: Increases predictive confidence in target validation by mapping functional ubiquitylation sites.
- Operational Value: Standardizes sample preparation and analytical protocols for reproducibility and scalability.
- Strategic Value: Informs go/no-go decisions by clarifying mechanistic ambiguity in centromere protein function.
- Portfolio Impact: Supports risk-adjusted prioritization of genome stability and cancer progression targets.
Implementation Considerations
- Requires expertise in immunoprecipitation, mass spectrometry, and protein modification analysis.
- Demands access to high-resolution LC-MS/MS instrumentation and specialized data analysis software.
- Necessitates cross-team standardization of sample preparation and data interpretation protocols.
- May require adaptation for different protein tags or model systems to ensure modification detection fidelity.
- Technical limitations exist for visualizing ubiquitylation in living cells or at single-cell resolution.
Biopharma FAQs
Chapters in this video
0:04
Introduction
0:44
In Vivo Ubiquitylation Assays Using pQCXIP-EYFP-CENP-A
2:19
Mass Spectrometry to Identify the Ubiquitylation Site of the EYFP-CENP-A K124R Mutant
4:55
Data Analysis
6:22
Results: EYFP-CENP-A K124 Mutant is Ubiquitylated and Interacts with HJURP
8:12
Conclusion
