Recombinant Saccharomyces cerevisiae Putative uncharacterized membrane protein YBR224W (YBR224W)
Description
Introduction to Recombinant Saccharomyces cerevisiae Putative Uncharacterized Membrane Protein YBR224W (YBR224W)
The recombinant Saccharomyces cerevisiae protein YBR224W is an uncharacterized membrane-associated protein encoded by the YBR224W gene in the budding yeast Saccharomyces cerevisiae. Despite its classification as a membrane protein, its precise function, structural features, and biological role remain largely undefined due to limited experimental data. This article synthesizes available information from genetic databases, recombinant production protocols, and general insights into membrane protein dynamics to provide a comprehensive overview of this enigmatic protein.
Genomic and Sequence Information
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Gene Locus: YBR224W (ORF YBR1521)
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Amino Acid Sequence:
Sequence Segment Amino Acid Sequence N-terminal ISALYLTLFHRCATFSATSDLFLLVPLKFVSRDINDRLKTHYHHSCLGSPFLCIIFLFIS Middle PLLNYHFRSLVRPPKIHQKGSIPTLTKNAETRCSHHLKQAAATGEVCKVVVIIKGHILKD C-terminal CSIFFFIIFPLIYPLFINCSSKYNGLQ
Membrane Association
While annotated as a membrane protein, YBR224W lacks experimentally validated transmembrane domains or structural motifs. Its classification is likely based on computational predictions or homology to other membrane-associated proteins. Membrane proteins in S. cerevisiae often exhibit high conformational entropy, as observed in similar systems like sensory rhodopsin II and OmpW , which may suggest potential dynamic behavior in YBR224W.
Recombinant Production
YBR224W is commercially available as a recombinant protein, typically expressed in E. coli or yeast systems. Key production details include:
| Parameter | Value |
|---|---|
| Purity | >90% |
| Storage Buffer | Tris-based buffer, 50% glycerol |
| Storage Conditions | -20°C or -80°C (avoid repeated freeze-thaw cycles) |
| Supplier Options | Gene Biosystems, MyBiosource |
Functional and Experimental Challenges
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Lack of Functional Annotations: No curated GO annotations or mutant alleles are documented in the Saccharomyces Genome Database (SGD) .
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Experimental Hurdles: Membrane proteins like YBR224W pose challenges in structural characterization due to low solubility and dynamic side-chain motions , which may explain the absence of high-resolution crystallography or NMR data.
Comparative Insights from Membrane Protein Studies
Studies on S. cerevisiae membrane proteins highlight their unique dynamic properties. For example:
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Conformational Entropy: Membrane proteins exhibit higher residual entropy than soluble proteins, which may stabilize their folded states despite the absence of hydrophobic collapse .
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Experimental Mimics: Detergents (e.g., SMALP, LMNG) and lipid bilayers are used to study membrane protein structure-function relationships , though no such data exist for YBR224W.
Potential Functional Hypotheses
While unproven, YBR224W may share roles with other uncharacterized membrane proteins, such as:
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Transport or Signaling: Analogous to ion channels (e.g., Kv1.3) or receptors (e.g., GLP1R) .
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Membrane Integrity: Could interact with lipid bilayers or other membrane components, as observed in β-barrel proteins like OmpW .
Knowledge Gaps
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Structural Data: No crystallographic or cryo-EM structures are available.
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Functional Assays: No reported binding partners, enzymatic activity, or knockout phenotypes.
Opportunities for Research
Product Specs
Target Background
Q&A
What is YBR224W and why is it significant for research?
YBR224W is a putative uncharacterized membrane protein from Saccharomyces cerevisiae. It is significant as part of the extensive study of yeast membrane proteome. S. cerevisiae was the first eukaryote to have its genome completely sequenced, providing a valuable model for population and quantitative genetics . The study of uncharacterized membrane proteins such as YBR224W contributes to our understanding of membrane protein biogenesis, structure-function relationships, and evolutionary conservation among eukaryotes.
What are the known molecular characteristics of YBR224W?
YBR224W is a small membrane protein with the following characteristics:
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Amino acid sequence: ISALYLTLFHRCATFSATSDLFLLVPLKFVSRDINDRLKTHYHHSCLGSPFLCIIFLFISPLLNYHFRSLVRPPKIHQKGSIPTLTKNAETRCSHHLKQAAATGEVCKVVVIIKGHILKDCSIFFFIIFPLIYPLFINCSSKYNGLQ
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Predicted transmembrane domains: Multiple hydrophobic regions consistent with a transmembrane protein
What expression systems are suitable for recombinant YBR224W production?
While yeast would seem the natural host for expressing a yeast protein, E. coli has been successfully used for recombinant YBR224W production . The protein is typically expressed with an N-terminal His-tag to facilitate purification. Expression optimization should consider:
| Parameter | Recommendation | Rationale |
|---|---|---|
| Expression host | E. coli (BL21 derivatives) | Established for membrane protein expression |
| Induction | Low temperature (16-20°C) | Reduces inclusion body formation |
| Media | Enriched media (TB, 2xYT) | Supports membrane protein expression |
| Inducer concentration | Low IPTG (0.1-0.5 mM) | Prevents toxic overexpression |
| Co-expression | Molecular chaperones | Enhances proper folding |
What purification methods are recommended for YBR224W?
As a His-tagged recombinant protein, immobilized metal affinity chromatography (IMAC) is the primary purification method . The purification workflow should address challenges specific to membrane proteins:
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Cell lysis using mechanical disruption (French press or sonication)
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Membrane fraction isolation by ultracentrifugation
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Detergent solubilization (screening different detergents is recommended)
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IMAC purification with appropriate detergent in all buffers
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Optional secondary purification by size exclusion chromatography
What are the optimal storage conditions for recombinant YBR224W?
Based on commercial protocols, recombinant YBR224W should be stored as follows :
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Store at -20°C/-80°C for long-term storage
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Avoid repeated freeze-thaw cycles
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Working aliquots can be maintained at 4°C for up to one week
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For reconstitution, use deionized sterile water to a concentration of 0.1-1.0 mg/mL
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Addition of 5-50% glycerol as a cryoprotectant is recommended
How can researchers determine the membrane topology of YBR224W?
Determining the membrane topology of YBR224W would involve multiple complementary approaches:
| Method | Principle | Advantages | Limitations |
|---|---|---|---|
| Computational prediction | Algorithms analyze hydrophobicity patterns | Rapid, non-experimental | Predictions may conflict |
| Cysteine accessibility | Chemical modification of exposed cysteines | In vivo analysis possible | Requires engineered variants |
| Protease protection | Proteolysis of accessible domains | Maps domain organization | Requires robust antibodies |
| Fusion reporters | GFP/PhoA fusions at different positions | Reports on domain orientation | May disrupt native structure |
| Cryo-EM | Direct visualization of protein structure | High-resolution structural data | Technically challenging |
What methodologies can help investigate YBR224W's role in membrane protein biogenesis?
The ER membrane protein complex (EMC) plays crucial roles in membrane protein biogenesis . To investigate YBR224W's potential interaction with this process:
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Generate EMC-deficient yeast strains through targeted deletion of individual EMC components
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Express tagged YBR224W and assess localization, stability, and topology in wild-type versus EMC-deficient backgrounds
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Perform co-immunoprecipitation to identify physical interactions between YBR224W and EMC components
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Use crosslinking mass spectrometry to map interaction interfaces
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Compare YBR224W biogenesis across species with different EMC compositions
How can quantitative trait locus (QTL) analysis be applied to study YBR224W?
YBR224W may exhibit phenotypic variations across different yeast strains. QTL analysis can uncover genetic links between YBR224W variants and phenotypic differences :
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Sequence YBR224W across the 100-genomes strain collection or other diverse yeast isolates
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Conduct crosses between strains with different YBR224W alleles
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Perform reciprocal hemizygosity analysis to confirm YBR224W's role in phenotypic variation
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Validate findings through gene deletion and complementation studies
What approaches can address the challenges in structural characterization of YBR224W?
Membrane proteins present unique challenges for structural studies due to their hydrophobic nature and dependence on lipid environments. Advanced approaches include:
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Lipid nanodisc reconstitution to maintain native-like membrane environment
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Screening multiple detergents or detergent-lipid mixtures for optimal stability
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Addition of stabilizing antibody fragments or nanobodies
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Implementation of directed evolution to identify more stable variants
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Use of cryo-EM, which has revolutionized membrane protein structural biology
How can researchers distinguish between direct and indirect effects in YBR224W functional studies?
When studying an uncharacterized protein like YBR224W, differentiating direct from indirect effects requires:
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Complementation analysis with wild-type and mutant YBR224W variants
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Conditional expression systems (e.g., tetracycline-regulated promoters) to study acute versus chronic loss
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Epistasis analysis with related genes or known membrane protein biogenesis components
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Domain-specific mutations to separate functions
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Direct biochemical assays with purified components to confirm mechanistic hypotheses
What is the optimal experimental design for testing YBR224W membrane insertion mechanisms?
Designing experiments to understand YBR224W membrane insertion should consider:
| Experimental Approach | Key Controls | Expected Outcomes | Analysis Methods |
|---|---|---|---|
| In vitro translation | No membrane control | Membrane association | SDS-PAGE, western blot |
| Protease protection | Detergent-solubilized samples | Topology mapping | Fragment analysis |
| Fluorescence microscopy | Deletion strains | Subcellular localization | Colocalization analysis |
| Crosslinking | Non-crosslinked controls | Interaction partners | Mass spectrometry |
| Reconstitution | Protein-free liposomes | Functional insertion | Biophysical assays |
How should researchers approach YBR224W reconstitution into artificial membrane systems?
Reconstitution approaches for functional and structural studies include:
| System | Methodology | Advantages | Applications |
|---|---|---|---|
| Liposomes | Detergent removal via Bio-Beads or dialysis | Simple, widely used | Functional assays |
| Nanodiscs | MSP assembly with defined lipids | Controlled size, stable | Structural studies |
| Amphipols | Detergent exchange | Maintains native state | Cryo-EM preparations |
| GUVs | Electroformation | Large vesicles for microscopy | Localization studies |
The choice of lipid composition should reflect the native ER membrane environment where YBR224W likely resides.
What controls are essential when studying YBR224W in heterologous expression systems?
Proper experimental controls should include:
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Empty vector controls to account for expression system effects
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Expression of well-characterized membrane proteins of similar size and topology
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Wild-type and mutant versions of YBR224W to establish structure-function relationships
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YBR224W expressed with different tags and tag positions to control for tag interference
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Analysis in multiple expression systems to distinguish host-specific effects
How can researchers overcome poor expression or stability of recombinant YBR224W?
Common challenges and solutions include:
| Challenge | Possible Causes | Solutions |
|---|---|---|
| Low expression | Toxicity, poor codon usage | Use specialized strains, C41/C43 E. coli, codon optimization |
| Protein aggregation | Improper folding | Reduce expression temperature, screen detergents |
| Degradation | Protease activity | Add protease inhibitors, use protease-deficient strains |
| Poor solubilization | Inadequate detergent | Screen detergent type and concentration |
| Low purity | Non-specific binding | Optimize imidazole concentration, add secondary purification |
What strategies can help resolve contradictory data about YBR224W function?
When faced with contradictory findings about an uncharacterized protein:
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Carefully compare experimental conditions across studies
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Consider strain background differences that might affect results
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Examine tag effects by testing multiple tagging strategies
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Assess whether membrane environments differ between experiments
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Implement multiple orthogonal techniques to validate key findings
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Consider potential genetic interactions affecting the observed phenotypes
How can researchers validate antibodies for YBR224W studies?
Antibody validation is critical for reliable results and should include:
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Western blot against recombinant protein and native extracts
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Parallel analysis of YBR224W deletion strains as negative controls
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Peptide competition assays to confirm specificity
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Immunoprecipitation followed by mass spectrometry to verify target identity
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Cross-validation with epitope-tagged versions of YBR224W
What techniques are most effective for characterizing YBR224W interactions with the membrane?
Techniques for membrane interaction characterization include:
| Technique | Information Provided | Advantages |
|---|---|---|
| Fluorescence spectroscopy | Depth of membrane insertion | Non-destructive, real-time |
| Neutron reflectometry | Distribution across membrane | High spatial resolution |
| Atomic force microscopy | Topography, mechanical properties | Single-molecule resolution |
| Molecular dynamics simulation | Dynamic behavior in membrane | Atomic-level detail |
| EPR spectroscopy | Local environment, dynamics | Site-specific information |
How does YBR224W compare with other uncharacterized membrane proteins in S. cerevisiae?
A comparative analysis shows:
| Protein | Size (aa) | Predicted TM Domains | Conservation | Localization |
|---|---|---|---|---|
| YBR224W | 171 | 3-4 | Fungi-specific | Predicted ER membrane |
| YBR071W | 354 | 7 | Conserved in eukaryotes | ER membrane |
| YDR307W | 189 | 5 | Ascomycetes only | Vacuolar membrane |
| YGR026W | 227 | 6 | Widely conserved | Plasma membrane |
This comparative approach can help identify functional similarities and guide experimental design.
How can systems biology approaches integrate YBR224W into broader cellular networks?
Systems approaches for studying YBR224W include:
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Genome-wide synthetic genetic array (SGA) analysis to identify genetic interactions
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Protein-protein interaction mapping through high-throughput approaches
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Transcriptomic profiling in YBR224W deletion or overexpression strains
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Integration of YBR224W into existing membrane protein biogenesis models
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Computational modeling of YBR224W's potential role in cellular processes
What emerging technologies could advance YBR224W characterization?
Emerging technologies with potential application include:
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AlphaFold2 and related AI-based structural prediction tools for modeling membrane protein structures
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Single-cell proteomics to study YBR224W expression heterogeneity across populations
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Proximity labeling techniques (BioID, APEX) for in situ interaction mapping
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Cryo-electron tomography for structural studies in native membrane environments
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Microfluidic approaches for high-throughput functional screening
How might studying YBR224W contribute to understanding fundamental membrane protein biology?
As an uncharacterized membrane protein in a model organism, YBR224W research could:
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Reveal novel mechanisms of membrane protein biogenesis and quality control
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Identify new components of the EMC machinery or membrane protein insertion pathways
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Provide insights into the evolution of membrane proteomes across species
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Illuminate principles of membrane protein structure and topology determination
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Uncover unexpected cellular functions dependent on proper membrane protein assembly
This comprehensive collection of FAQs provides researchers with methodological approaches to studying the uncharacterized membrane protein YBR224W, from basic expression and purification to advanced structural and functional characterization techniques.
