Overview of CDC42EP4 and Antibody Specifications

CDC42 effector protein 4 (CDC42EP4), also known as BORG4 or CEP4, is a member of the CDC42 effector protein family. These proteins interact with the GTP-bound form of CDC42 and are involved in regulating cytoskeletal organization, cell morphology, and intracellular signaling pathways. CDC42EP4 contains a CRIB (Cdc42/Rac interactive binding) motif that mediates its interaction with active CDC42.

The CDC42EP4 Mouse mAb (Ab348834) is a monoclonal antibody raised in mouse against the human CDC42EP4 protein. Its high specificity and affinity make it suitable for detecting endogenous levels of CDC42EP4 in relevant experimental systems. Researchers should consult the product datasheet for confirmed species reactivity, immunogen details, and storage conditions prior to use.

Sample Preparation Protocol

Cell Lysate Preparation:

1. Wash cells twice with ice-cold PBS to remove culture medium.
2. Add RIPA lysis buffer supplemented with protease inhibitor cocktail (1×) and phosphatase inhibitors if phosphorylation status is of interest.
3. Incubate on ice for 15–30 minutes with occasional vortexing.
4. Centrifuge at 12,000 × g for 15 minutes at 4°C to pellet cell debris.
5. Transfer supernatant to a fresh microcentrifuge tube and quantify protein concentration using a BCA or Bradford assay.
6. Prepare samples in SDS loading buffer and denature at 95°C for 5 minutes prior to electrophoresis.

Tissue Lysate Preparation:

1. Homogenize fresh or snap-frozen tissue in RIPA buffer with protease inhibitors on ice.
2. Centrifuge at 12,000 × g for 20 minutes at 4°C and collect the supernatant.
3. Quantify protein and proceed as above.

Note: Optimal lysis conditions may vary depending on cell type and tissue. Review flags apply to specific buffer recommendations not confirmed in the source datasheet.

Western Blot, Immunofluorescence & Immunoprecipitation Protocols

Western Blot (WB):

1. Resolve 20–40 µg of total protein by SDS-PAGE and transfer to a PVDF or nitrocellulose membrane.
2. Block membrane with 5% non-fat dry milk or 5% BSA in TBST for 1 hour at room temperature.
3. Incubate with CDC42EP4 Mouse mAb (Ab348834) at the manufacturer's recommended dilution overnight at 4°C with gentle agitation.
4. Wash membrane 3× with TBST (5 minutes each).
5. Incubate with appropriate HRP-conjugated anti-mouse secondary antibody for 1 hour at room temperature.
6. Wash 3× with TBST and detect using ECL substrate. Image using a chemiluminescence detection system.

Immunofluorescence (IF):

1. Fix cells with 4% paraformaldehyde for 15 minutes, then permeabilize with 0.1–0.2% Triton X-100 for 10 minutes.
2. Block with 5% normal serum for 1 hour.
3. Apply CDC42EP4 Mouse mAb at recommended dilution overnight at 4°C.
4. Wash with PBS and incubate with fluorophore-conjugated anti-mouse secondary antibody for 1 hour at room temperature, protected from light.
5. Mount with DAPI-containing mounting medium and image by confocal or fluorescence microscopy.

Immunoprecipitation (IP):

1. Pre-clear 500 µg lysate with Protein A/G agarose beads for 1 hour at 4°C.
2. Add CDC42EP4 Mouse mAb at recommended amount to pre-cleared lysate and incubate overnight at 4°C with rotation.
3. Add Protein A/G beads and incubate for 2 hours at 4°C.
4. Wash beads 3× with lysis buffer, elute with SDS loading buffer, and analyze by Western blot.

Note: Specific dilution ratios and amounts are not confirmed in the source material. Consult the product datasheet for validated dilutions. Review flags apply.

Troubleshooting Guide

The following table outlines common issues encountered when using CDC42EP4 Mouse mAb and suggested remedies:

• No signal (WB): Verify antibody dilution and incubation conditions. Confirm target protein expression in the chosen cell/tissue model. Check secondary antibody compatibility (must be anti-mouse). Ensure transfer efficiency.
• High background: Increase blocking time or concentration. Increase number and duration of wash steps. Optimize primary antibody dilution. Use 5% BSA instead of milk if detecting phosphoproteins.
• Multiple non-specific bands: Reduce primary antibody concentration. Confirm denaturation conditions. Consider running a positive control lysate confirmed to express CDC42EP4.
• Weak or inconsistent IF signal: Optimize fixation and permeabilization conditions. Ensure secondary antibody is directed against mouse IgG. Check fluorophore compatibility with available filter sets.
• Low IP yield: Increase antibody amount or extend incubation time. Optimize bead type (Protein A vs. Protein G depending on antibody subclass). Reduce non-specific binding by including additional wash steps.

Note: Specific validated troubleshooting data are not provided in the source material. These recommendations are based on standard immunological practice and should be confirmed against the product datasheet.

Storage, Handling & Safety Considerations

Storage: Store CDC42EP4 Mouse mAb (Ab348834) according to the conditions specified on the product datasheet. Antibodies are generally stored at –20°C for long-term storage. Avoid repeated freeze-thaw cycles, which can compromise antibody activity and specificity. Aliquoting is recommended upon first thaw.

Handling: Keep the antibody on ice during experimental setup. Use sterile, low-protein-binding microcentrifuge tubes to minimize adsorptive losses. Centrifuge briefly before opening to collect all liquid at the bottom of the tube.

Safety: This product is intended for research use only and is not approved for diagnostic or therapeutic use in humans or animals. Follow your institutional biosafety guidelines when handling biological reagents. Dispose of all biological waste in accordance with local regulations.

Note: Specific storage temperature, concentration, and formulation details are not confirmed in the provided source material. Please refer to the product datasheet for accurate storage and handling instructions. Review flags apply.