Recombinant Human GPR142 Protein: Handling & Usage Protocol

Recombinant Human GPR142 Protein is a purified recombinant form of the human G protein-coupled receptor 142, supplied by Aladdin Scientific (SKU: rp369401) for use in receptor binding studies, functional GPCR assays, and related biochemical research applications.

Product Name

Recombinant Human GPR142 Protein

SKU

rp369401

Protein Family

G Protein-Coupled Receptor (GPCR), Class A Rhodopsin-like

Species

Human (Homo sapiens)

Recommended Storage

Store at -80°C upon receipt; avoid repeated freeze-thaw cycles

Supplier Reference

absea#PQ-589

Background: GPR142 and Its Biological Relevance

GPR142 (G protein-coupled receptor 142) is a member of the Class A rhodopsin-like family of GPCRs. It is considered an orphan receptor, meaning its endogenous ligand(s) and complete physiological role have not been fully characterized in the scientific literature. GPR142 has been reported to be expressed predominantly in the pancreas, with additional expression noted in other tissues. Emerging research suggests a potential role in insulin secretion and glucose homeostasis, making it a candidate target for metabolic disease research.

The recombinant human GPR142 protein provided by Aladdin Scientific enables researchers to investigate receptor function, screen for potential ligands, and characterize downstream signaling pathways in vitro, supporting the broader field of GPCR drug discovery.

Materials Required

• Recombinant Human GPR142 Protein (Aladdin Scientific, SKU: rp369401)
• Appropriate reconstitution buffer (e.g., sterile phosphate-buffered saline, pH 7.4, or as specified on the Certificate of Analysis)
• Low-protein-binding microcentrifuge tubes
• Ice bucket or dry-ice container for handling
• Micropipettes and calibrated tips
• Aliquoting supplies for single-use preparation
• Suitable assay reagents for downstream application (e.g., binding assay kits, cAMP detection reagents, or calcium flux assay reagents)

Note: Always consult the Certificate of Analysis (CoA) supplied with each lot for lot-specific reconstitution volume, concentration, and purity data.

Reconstitution and Handling Protocol

1. Thawing: Remove the vial from -80°C storage and allow it to thaw slowly on ice (4°C) or at room temperature for no more than 10 minutes. Do not use a water bath above 37°C.
2. Centrifugation: Briefly centrifuge the vial (1,000–2,000 × g, 30 seconds) to collect any material from the walls and cap before opening.
3. Reconstitution: If supplied as a lyophilized powder, add the recommended volume of sterile reconstitution buffer (refer to CoA) dropwise along the side of the vial. Gently swirl to dissolve; do not vortex. Allow 10 minutes at room temperature for complete dissolution.
4. Aliquoting: Divide the reconstituted protein into single-use aliquots in low-protein-binding tubes to minimize freeze-thaw cycles. Label each aliquot with date, concentration, and lot number.
5. Storage of Aliquots: Store working aliquots at -20°C to -80°C. For short-term use (within 1 week), aliquots may be stored at 4°C. Avoid repeated freeze-thaw cycles, as these can reduce protein activity.
6. Protein Concentration Verification: If required, verify protein concentration using a microBCA or Bradford assay prior to use in downstream applications.

Important: Handle the protein on ice at all times during experimental setup to preserve biological activity.

Downstream Assay Applications

Recombinant Human GPR142 Protein (rp369401) is suitable for a range of in vitro research applications, including but not limited to:

• Ligand Binding Assays: Use the recombinant protein to screen compound libraries or identify putative endogenous ligands for GPR142 via radioligand or fluorescence-based competitive binding assays.
• Functional GPCR Signaling Assays: Reconstitute GPR142 into lipid vesicles or cell-free systems to study G protein coupling, cAMP modulation, or calcium mobilization in response to candidate agonists or antagonists.
• Antibody Validation: Use as a positive control antigen for validating GPR142-specific antibodies in ELISA, Western blot, or immunoprecipitation experiments.
• Structural Studies: Suitable as a component for biophysical characterization methods such as surface plasmon resonance (SPR) or microscale thermophoresis (MST) to determine binding kinetics of small molecules or biologics.

Disclaimer: Optimal working concentrations and assay conditions should be empirically determined for each specific experimental system. Refer to relevant primary literature and the product CoA for guidance.

Troubleshooting and Quality Considerations

If suboptimal results are observed, consider the following troubleshooting steps:

• Low or No Activity: Confirm the protein has not undergone more than two freeze-thaw cycles. Verify reconstitution buffer composition and pH. Ensure working concentrations are within the recommended range per the CoA.
• Precipitation: Centrifuge the reconstituted solution at 10,000 × g for 5 minutes at 4°C to remove aggregates before use. Avoid storing reconstituted protein at concentrations above the recommended maximum.
• Inconsistent Assay Results: Ensure all reagents are equilibrated to the same temperature before combining. Use freshly prepared assay buffer and verify instrument calibration.
• Protein Degradation: If degradation is suspected (e.g., loss of activity over time at 4°C), aliquot and store at -80°C immediately after reconstitution.

For additional technical support, contact Aladdin Scientific customer service and reference SKU rp369401 and the lot number from your CoA.

Frequently asked questions

What is the recommended reconstitution buffer for Recombinant Human GPR142 Protein?

The recommended reconstitution buffer and volume are specified on the Certificate of Analysis (CoA) provided with each lot of rp369401. As a general guideline, sterile phosphate-buffered saline (PBS, pH 7.4) containing a carrier protein such as 0.1% BSA is commonly used for recombinant GPCR proteins to maintain stability, but users should always defer to the lot-specific CoA for precise instructions.

How should I store Recombinant Human GPR142 Protein to maintain its activity?

Upon receipt, the protein should be stored at -80°C. After reconstitution, prepare single-use aliquots and store at -80°C for long-term stability or at -20°C for short-term use. Avoid repeated freeze-thaw cycles, as they can compromise protein integrity and biological activity. For immediate short-term use within one week, aliquots may be kept at 4°C.

What applications is Recombinant Human GPR142 Protein suitable for?

Recombinant Human GPR142 Protein (rp369401) is suitable for in vitro research applications including ligand binding assays, functional GPCR signaling studies, antibody validation (e.g., ELISA and Western blot positive controls), and biophysical characterization methods such as surface plasmon resonance (SPR) and microscale thermophoresis (MST). Optimal conditions should be determined empirically for each application.

Is GPR142 an orphan receptor, and what is its known biological function?

Yes, GPR142 is classified as an orphan GPCR, meaning its endogenous ligand has not been conclusively identified. It is predominantly expressed in the pancreas and has been associated with potential roles in insulin secretion and glucose metabolism based on available research data, making it a subject of interest for metabolic disease and drug discovery research.

References

1. Fredriksson R, Lagerström MC, Lundin LG, Schiöth HB. The G-protein-coupled receptors in the human genome form five main families. Phylogenetic analysis, paralogon groups, and fingerprints. Mol Pharmacol. 2003;63(6):1256-1272. doi:10.1124/mol.63.6.1256
2. Isberg V, Mordalski S, Munk C, et al. GPCRdb: an information system for G protein-coupled receptors. Nucleic Acids Res. 2016;44(D1):D356-D364. doi:10.1093/nar/gkv1178
3. Absea Biotechnology. Product Data Sheet: Recombinant Human GPR142 Protein, Reference PQ-589. Absea Biotechnology Ltd.

Products are supplied for research and development use only. Not for use in humans, animals, diagnosis, or therapy.