Recombinant Human GARNL3 Protein: Protocol & Usage Guide

Recombinant Human GARNL3 Protein is a research-grade reagent designed for use in biochemical, cell-based, and protein–protein interaction studies targeting the GTPase-activating Rap/Ran-GAP domain-containing signaling axis.

Product Name

Recombinant Human GARNL3 Protein

SKU

rp372904

Protein Origin

Human (Homo sapiens)

Form

Recombinant protein; consult datasheet for exact formulation details

Recommended Storage

Store at -80 °C for long-term; avoid repeated freeze-thaw cycles

Application

Biochemical assays, protein interaction studies, cell-based functional assays

Background: GARNL3 Protein Biology

GARNL3 (GTPase Activating Rap/RanGAP Domain-Like 3), also referred to as RASAL3 in some literature, is a member of the RasGAP superfamily. It contains a conserved GAP domain that accelerates the intrinsic GTPase activity of Ras-family small GTPases, thereby negatively regulating downstream Ras/MAPK and related signaling cascades. GARNL3 has been implicated in immune cell function, particularly in the regulation of lymphocyte activation and differentiation, and has emerged as a subject of interest in oncology and immunology research. Recombinant Human GARNL3 Protein produced for research purposes enables investigators to study its enzymatic activity, binding partners, and regulatory roles in vitro without reliance on endogenous expression systems.

Reconstitution Protocol

Prior to reconstitution, briefly centrifuge the vial at low speed (e.g., 1,000 × g for 30 seconds) to collect any lyophilized material settled on the walls or cap. Reconstitute the protein in sterile, ultrapure water or an appropriate buffer as specified on the product datasheet. Typical reconstitution buffers include PBS (pH 7.4) supplemented with a carrier protein such as 0.1% BSA to enhance stability and minimize adsorption losses.

Steps:

1. Allow the vial to equilibrate to room temperature for 5–10 minutes before opening.
2. Add the recommended volume of reconstitution buffer slowly along the inner wall of the vial.
3. Gently swirl or pipette to mix; do NOT vortex, as this may denature the protein.
4. Allow the solution to stand at room temperature for 5 minutes to ensure complete dissolution.
5. Inspect visually for clarity; discard if particulates are observed.

Refer to the specific product datasheet for the exact reconstitution volume and buffer composition for SKU rp372904.

Storage, Stability, and Handling

Short-term storage: Reconstituted protein may be stored at 4 °C for up to 1 week if carrier protein (e.g., BSA) is included in the formulation. Monitor for signs of precipitation or activity loss.

Long-term storage: Aliquot the reconstituted protein into single-use volumes to avoid repeated freeze-thaw cycles, and store at -80 °C. Each freeze-thaw cycle can progressively reduce protein activity and integrity.

General handling guidelines:

• Work on ice whenever possible to minimize thermal degradation.
• Use low-protein-binding tubes and pipette tips to reduce surface adsorption.
• Avoid exposure to detergents or denaturing agents unless required by the specific assay.
• Record lot number and date of reconstitution for traceability.

Specific stability data for SKU rp372904 should be confirmed from the product datasheet or by contacting Aladdin Scientific technical support.

Application Guidelines for Common Assays

Recombinant Human GARNL3 Protein is suitable for a range of in vitro research applications. The following general guidance applies; always optimize conditions empirically for your specific experimental system:

GTPase Activity Assays: GARNL3 can be used as a GAP-domain reagent to assess its stimulatory effect on GTP hydrolysis by target small GTPases (e.g., Ras family members). Colorimetric or fluorescence-based phosphate release assays (e.g., malachite green or MESG/purine nucleoside phosphorylase-coupled assays) are commonly employed.

Protein–Protein Interaction Studies: Use pull-down assays, co-immunoprecipitation setups, or surface plasmon resonance (SPR) to characterize interactions between GARNL3 and putative binding partners. Ensure the protein is maintained in native conformation by avoiding harsh denaturing conditions.

Western Blot Positive Control: Recombinant GARNL3 may serve as a positive control or molecular weight marker for anti-GARNL3 antibody validation in Western blot experiments.

ELISA Standard: The recombinant protein can be used to generate standard curves in sandwich ELISA formats designed to quantify endogenous GARNL3 levels in biological samples.

All working concentrations should be titrated empirically. Refer to peer-reviewed literature and the Aladdin Scientific product datasheet for suggested starting concentrations.

Quality Control and Troubleshooting

Quality Control: Each lot of Recombinant Human GARNL3 Protein undergoes standard QC testing that typically includes SDS-PAGE or Coomassie staining to assess purity, and where applicable, functional activity testing. The certificate of analysis (CoA) accompanying each shipment provides lot-specific purity, concentration, and endotoxin data. Always review the CoA before use.

Common Issues and Troubleshooting:

Issue	Possible Cause	Recommended Action
Precipitation after reconstitution	Incorrect buffer, excessive vortexing, or protein aggregation	Centrifuge gently (10,000 × g, 5 min, 4 °C) and use supernatant; verify buffer composition
Low or no activity	Freeze-thaw degradation or improper storage	Use freshly reconstituted aliquots; ensure -80 °C storage
Non-specific bands on WB	Antibody cross-reactivity or protein degradation	Check protein integrity by SDS-PAGE; verify antibody specificity
High background in ELISA	Protein adsorption or buffer incompatibility	Add BSA or blocking agent; optimize wash steps

For additional technical assistance, contact Aladdin Scientific customer support with your lot number and experimental details.

Frequently asked questions

What is the recommended reconstitution buffer for Recombinant Human GARNL3 Protein?

The reconstitution buffer should be as specified on the product datasheet for SKU rp372904. In general, sterile PBS (pH 7.4) supplemented with 0.1% BSA is commonly recommended for recombinant proteins to maintain stability and minimize adsorptive losses. Always consult the CoA and datasheet for lot-specific instructions.

How should Recombinant Human GARNL3 Protein be stored to maintain activity?

For long-term storage, aliquot the reconstituted protein into single-use volumes and store at -80 °C to avoid repeated freeze-thaw cycles. For short-term use within one week, storage at 4 °C is acceptable if the formulation contains a stabilizing carrier protein such as BSA. Avoid freeze-thaw cycles, as each cycle can progressively reduce protein integrity and activity.

What applications is Recombinant Human GARNL3 Protein validated for?

Recombinant Human GARNL3 Protein is suitable for applications including GTPase activity assays, protein–protein interaction studies (pull-down, co-IP, SPR), Western blot positive control, and ELISA standard curve generation. Specific validated applications for SKU rp372904 are detailed on the product datasheet; users should confirm suitability and optimize conditions for their particular assay system.

How can I verify the purity and integrity of Recombinant Human GARNL3 Protein upon receipt?

Upon receipt, review the Certificate of Analysis (CoA) included with the shipment for lot-specific purity, concentration, and endotoxin data typically assessed by SDS-PAGE and Coomassie staining. You may also run your own SDS-PAGE to confirm the expected molecular weight band and assess degradation. Contact Aladdin Scientific technical support if results are inconsistent with the CoA.

References

1. Kupzig S, et al. GAP1 family members constitute bifunctional Ras and Rap GTPase-activating proteins. J Biol Chem. 2006;281(15):9891-9900.
2. Bernards A. GAPs galore! A survey of putative Ras superfamily GTPase activating proteins in man and Drosophila. Biochim Biophys Acta. 2003;1603(2):47-82.
3. Aladdin Scientific. Recombinant Human GARNL3 Protein (rp372904) Product Datasheet. Aladdin Scientific.

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