Recombinant Dog Olfactory receptor-like protein OLF2
Description
Genetic Organization and Expression
The OLF2 gene is part of a complex family of olfactory receptor genes in canines. Research has revealed that canine olfactory receptor genes are organized into distinct subfamilies with varying numbers of members, from as few as 2 to as many as 20 members per subfamily . Analysis of Southern hybridization experiments has shown that members of the same subfamily are typically clustered together in the genome, and some subfamilies may be closely linked .
Expression Systems and Methods
Recombinant dog OLF2 protein has been successfully produced using multiple expression systems, each offering different advantages for research applications. The two primary expression systems used commercially are:
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E. coli expression system: This bacterial system is widely used for producing the full-length (1-311aa) protein with N-terminal His-tags .
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Yeast expression system: This eukaryotic system is utilized for certain partial protein forms and may offer advantages in post-translational modifications .
The choice of expression system depends on the specific research requirements, with E. coli systems generally providing higher yields but potentially lacking some post-translational modifications that might be achieved in eukaryotic systems.
Reconstitution Protocol
For proper reconstitution of lyophilized OLF2 protein, the following protocol is recommended:
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Briefly centrifuge the vial prior to opening to bring contents to the bottom
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Reconstitute in deionized sterile water to a concentration of 0.1-1.0 mg/mL
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For long-term storage, add glycerol to a final concentration of 5-50% (typically 50%)
The reconstituted protein can be used for various research applications, including structural studies, functional assays, and antibody production.
Role in Olfactory Signal Transduction
As an olfactory receptor, OLF2 functions as a chemoreceptor that detects odorant molecules in the environment . The general mechanism of olfactory reception involves:
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Binding of odorant molecules to the receptor protein
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Conformational changes in the receptor structure
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Activation of olfactory-type G proteins (Golf and/or Gs)
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Activation of adenylate cyclase, converting ATP to cyclic AMP (cAMP)
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Opening of cyclic nucleotide-gated ion channels
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Influx of calcium and sodium ions, depolarizing the olfactory neuron
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Generation of action potentials that transmit odor information to the brain
Rather than binding specific ligands exclusively, olfactory receptors like OLF2 typically display affinity for a range of odor molecules based on their molecular volumes and physio-chemical properties . Conversely, a single odorant molecule may bind to multiple olfactory receptors with varying affinities, creating a complex combinatorial code for odor recognition .
Expression in Non-Olfactory Tissues
Intriguingly, research has discovered that some olfactory receptors, including certain dog olfactory receptor genes, are expressed in tissues beyond the olfactory system . A subset of olfactory receptor genes has been found to be predominantly expressed in the testis rather than the olfactory mucosa .
Western blotting has confirmed the presence of a 40-kD immunoreactive protein in the membrane of mature sperm cells, and immunodetection methods have localized these receptors in late round and elongated spermatids, as well as in the cytoplasmic droplet during sperm cell maturation, and on the tail midpiece of mature spermatozoa . This unexpected pattern of expression suggests a potential role as sensors for unidentified chemicals possibly involved in the control of mammalian sperm maturation, migration, and/or fertilization .
Evolutionary Studies of Canid Olfaction
Recombinant OLF2 and related olfactory receptors have contributed significantly to comparative studies of olfactory systems between domestic dogs and their wild canid relatives. Recent research has revealed that domestic dogs may have lost some functional olfactory receptor genes during domestication, coinciding with a documented reduction in nasal morphology .
Analysis of functional olfactory receptor gene (FORG) repertoires has shown that domestic dogs have, on average, significantly fewer FORG than either wolves alone or wolves and coyotes combined . This finding suggests an evolutionary shift in olfactory capacity associated with the domestication process.
Breed Comparison Studies
Contrary to popular assumptions, research comparing olfactory receptor gene repertoires across different dog breeds has yielded surprising results. Comprehensive studies examining both morphological features and genetic profiles have found no significant differences in olfactory anatomy or olfactory receptor gene repertoire size between breeds traditionally associated with scent detection (such as scent hounds) and other breeds .
The table below summarizes key findings from breed comparison studies:
| Parameter Examined | Findings Between Breed Groups | Significance |
|---|---|---|
| Functional OR gene number | No significant differences between scent and non-scent breeds | Challenges assumptions about genetic basis of scent ability |
| Relative cribriform plate size | No significant differences among domestic dog breeds | Suggests morphological similarity in olfactory structure |
| OR gene expression | No discernible pattern corresponding to breed groupings | Indicates similar molecular olfactory capacity |
These findings suggest that superior scent detection abilities in certain dog breeds likely stem from advantageous behavioral traits and training rather than genetic or morphological advantages in their olfactory systems .
Implications for Understanding Olfaction
The study of recombinant olfactory receptors like OLF2 provides valuable insights into the molecular mechanisms underlying the sense of smell. By examining the structure-function relationships of these receptors, researchers can better understand how the olfactory system discriminates between thousands of different odors with remarkable sensitivity and specificity.
Research on canine olfactory receptor genes has also demonstrated the stability of gene subfamily numbers across diverse dog breeds, despite differential selection pressures based on olfactory acuity in various breed categories such as scent hounds, sight hounds, and toy breeds . This stability suggests that the basic genetic architecture of the olfactory system is conserved across different canine populations.
Current Product Offerings
Recombinant dog olfactory receptor-like protein OLF2 is available commercially from several biotechnology suppliers. These products are designed primarily for research applications, including antibody production, protein-protein interaction studies, functional assays, and structural analyses.
Current commercial offerings include:
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Full-length recombinant protein (1-311aa) with N-terminal His-tag expressed in E. coli (Product code: RFL438CF)
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Partial length recombinant protein expressed in E. coli (Product code: CSB-EP850129DO1)
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Partial length recombinant protein expressed in yeast (Product code: CSB-YP850129DO1)
These products are typically available in quantities suitable for laboratory research and are not intended for human consumption or diagnostic use .
Research and Diagnostic Applications
The recombinant OLF2 protein has potential applications in various research areas:
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Antibody production: Generation of specific antibodies for detection and localization studies
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Protein-protein interaction studies: Investigation of binding partners and signaling pathways
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Structural studies: Analysis of receptor conformation and binding sites
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Comparative genomics: Examination of evolutionary relationships between species
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Functional assays: Testing of receptor activation by potential ligands
The development of more sophisticated assays using recombinant olfactory receptors may potentially lead to applications in environmental monitoring, food safety testing, and medical diagnostics in the future.
Product Specs
Note: While we prioritize shipping the format currently in stock, please specify your format preference during order placement for customized preparation.
Note: Standard shipping includes blue ice packs. Dry ice shipping requires advance notification and incurs additional charges.
The tag type is determined during production. If you require a specific tag, please inform us; we will prioritize its development.
Target Background
Q&A
Basic Research Questions
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What is dog olfactory receptor-like protein OLF2 and what are its key characteristics?
Dog olfactory receptor-like protein OLF2 (UniProt ID: Q95155) is a membrane protein involved in the canine olfactory system. It consists of 311 amino acids and functions as a receptor-like protein potentially involved in odorant detection pathways. The protein is typically expressed with a His-tag to facilitate purification and detection in research settings .
Property Details Full Name Olfactory receptor-like protein OLF2 UniProt ID Q95155 Protein Length Full Length (1-311 amino acids) Source E. coli expression system Tag His-tag (N-terminal) Form Lyophilized powder -
What are the recommended storage and handling procedures for recombinant dog OLF2?
For optimal stability and activity, the following storage and handling protocols are recommended :
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Store lyophilized protein at -20°C/-80°C upon receipt
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Aliquot reconstituted protein to avoid repeated freeze-thaw cycles
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Working aliquots may be stored at 4°C for up to one week
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Reconstitution should be performed in deionized sterile water to 0.1-1.0 mg/mL
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For long-term storage, add glycerol to a final concentration of 5-50% (default 50%)
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The protein is typically supplied in Tris/PBS-based buffer with 6% Trehalose, pH 8.0
Repeated freezing and thawing should be avoided as it can compromise protein integrity and function .
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What expression systems are used for recombinant dog OLF2 production?
Based on the available information, recombinant dog OLF2 is primarily expressed in Escherichia coli (E. coli) expression systems . The protein is typically fused with an N-terminal His-tag to facilitate purification using affinity chromatography. The expressed protein undergoes purification processes to achieve >90% purity as determined by SDS-PAGE analysis .
Advanced Research Questions
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How should experiments be designed to effectively study the function of recombinant dog OLF2?
Designing rigorous experiments for olfactory receptor proteins requires careful planning and consideration of multiple variables. Based on statistical design principles for animal research :
a) Objective Design:
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Clearly define research objectives (e.g., ligand binding specificity, signal transduction)
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Select appropriate controls (positive, negative, vehicle)
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Identify dependent and independent variables
b) Experimental Variables to Control:
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Protein preparation consistency (expression, purification, storage)
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Environmental conditions (temperature, pH, ionic strength)
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Detection methods sensitivity and specificity
c) Blocking and Randomization:
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Follow the principle: "control what you can, block what you cannot, and randomize the rest"
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Use statistical blocking to account for variables that cannot be fully controlled
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Implement computer-generated randomization to avoid human-introduced patterns
d) Sample Size Determination:
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Conduct power analysis to determine appropriate sample sizes
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Consider both statistical significance and biological relevance
A well-designed factorial experiment can efficiently evaluate multiple factors simultaneously while minimizing resource use .
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What analytical methods are recommended for detecting and quantifying recombinant dog OLF2?
Several complementary analytical techniques can be employed for detection and quantification :
a) Immunological Methods:
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ELISA: Specific detection and quantification with high sensitivity
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Western Blotting: Using anti-His antibodies for tagged protein detection
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Immunohistochemistry: For tissue localization studies
b) Biochemical Analysis:
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Size Exclusion Chromatography: For oligomerization state determination
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Mass Spectrometry: For precise molecular weight determination and post-translational modifications
c) Functional Assays:
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Ligand binding assays
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GPCR activation assays (if receptor functionality is preserved)
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Calcium flux measurements
The choice of method should align with specific research questions and available resources.
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How can contradictions in experimental data related to recombinant dog OLF2 be systematically analyzed and resolved?
Data contradictions are common in complex biological systems and require systematic approaches for resolution :
a) Contradiction Classification:
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Implement a notation system using parameters (α, β, θ) where:
b) Context-Based Analysis:
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Examine if contradictions stem from omitted contextual information
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Consider tissue specificity, experimental conditions, or protein states
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Evaluate whether contradictions represent true biological variability
c) Methodological Assessment:
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Review normalization methods for biological entities
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Evaluate co-reference resolution across experimental descriptions
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Consider experimental variability and reproducibility
d) Resolution Strategies:
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Document contexts that qualify seemingly contradictory statements
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Perform meta-analysis across multiple studies
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Design experiments specifically targeted at resolving contradictions
When synthesizing literature on OLF2, researchers should be aware that apparent contradictions may reflect different experimental contexts rather than fundamental disagreements .
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How can experimental design principles be applied to study recombinant dog OLF2 while minimizing animal usage?
Applying the 3Rs principles (Replacement, Reduction, and Refinement) to OLF2 research :
a) Experimental Design Optimization:
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Use factorial designs to test multiple variables simultaneously
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Implement Graeco-Latin squares for multiple measurements from the same animals
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Apply blocking to reduce variance and increase statistical power
b) Sample Size Calculation:
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Perform power analysis before experimentation
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Account for expected effect sizes and variability
Morning Afternoon (a) Male control (a) Male treatment (b) Female treatment (b) Male treatment (c) Female treatment (c) Female control (d) Female control (d) Female control (e) Male treatment (e) Male control (f) Male control (f) Female treatment Example of a balanced measurement plan that could be adapted for OLF2 research
c) In Vitro Alternatives:
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Leverage cell-based assays before proceeding to animal models
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Use heterologous expression systems to study receptor function
d) Statistical Analysis Planning:
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Develop analysis methodology before experimentation
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Account for potential sources of variability in the analysis
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What approaches can be used to evaluate the immunological properties of recombinant dog OLF2?
Drawing from research on other recombinant canine proteins :
a) Antigenicity Assessment:
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Skin prick tests (SPT) to evaluate immediate hypersensitivity reactions
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ELISA and IgE immunoblotting to detect antibody binding
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Inhibition assays to determine specificity of antibody recognition
b) Immune Response Stimulation:
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Peripheral blood mononuclear cell (PBMC) proliferation assays
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Cytokine production measurement (e.g., IFN-γ production)
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Combination with other immunomodulators (e.g., IL-2, IL-12) to enhance responses
c) Cross-reactivity Analysis:
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Comparison with natural OLF2 protein
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Assessment of concordance between reactions to recombinant and natural proteins
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Phi coefficient calculation for statistical evaluation of concordance
These approaches can help characterize both the antigenicity and immunogenicity of recombinant dog OLF2.
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What strategies can overcome challenges in delivery and stability of recombinant dog OLF2 for in vivo studies?
Based on research with other recombinant proteins in canine models :
a) Encapsulation Techniques:
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Alginate microcapsules with increased concentration crosslinked with barium
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Lamination of capsule surface with poly-L-lysine and alginate for mechanical stability
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Gelled bead formation without core solubilization
b) Delivery Optimization:
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Assessment of delivery methods to achieve systemic distribution
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Monitoring of protein levels in plasma over time
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Evaluation of immune responses to the delivered protein
c) Stability Enhancement:
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Formulation with stabilizing excipients
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Optimization of storage conditions to maintain activity
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Protein engineering approaches to improve inherent stability
d) Biocompatibility Considerations:
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Monitoring for inflammatory responses to delivery vehicles
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Assessment of long-term viability of implanted cells or materials
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Strategies to reduce immunogenicity of the delivery system
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How can contradictions in scientific literature about olfactory receptors be effectively managed in research?
Managing contradictions in scientific literature requires systematic approaches :
a) Contradiction Sources Identification:
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Distinguishing between linguistic and scientific contradictions
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Identifying factive contradictions (statements about facts)
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Recognizing modal contradictions (statements about possibilities)
b) Domain-Specific Challenges:
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Entity normalization issues in molecular biology
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Co-reference resolution across complex pathway descriptions
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Interpretation of author stances on relationships between entities
c) Resolution Methodologies:
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Natural language inference techniques to detect contradictions
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Domain-specific corpora development for training contradiction detection systems
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Application of deep learning methods to recognize subtle linguistic patterns
d) Implementation for OLF2 Research:
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Creation of structured knowledge graphs of OLF2-related information
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Explicit documentation of experimental contexts
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Systematic review approaches to synthesize contradictory findings
Effective management of contradictions is essential for building reliable knowledge bases for computational approaches in olfactory receptor research .
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