This website uses cookies to ensure you get the best experience on our website.
- Table of Contents
CRABP2 / Cellular retinoic acid-binding protein 2 · Western blot design guide
Design a Western Blot for CRABP2
Real validated CRABP2 Western blot protocols, expected-band and isoform facts, troubleshooting for weak or shifted signal, and recommended anti-CRABP2 WB antibodies. Everything you need to plan the experiment before you commit precious samples.
Evidence assembled September 2026 · For research use; verify linked source records and product datasheet before use
CRABP2 Western Blot Experimental Design Guide
Expected bands, validated protocols, controls and antibodies — the at-a-glance facts below, then the full design guide.
Must know before running
| Expected band | ~15.7 kDa | |
| Observed band | ~17 kDa | |
| Gel | 5–20% (catalog A03297-3) | |
| Positive control | Endometrium (IHC candidate; verify WB) +4 more | |
| Negative control | Adipose tissue (IHC candidate; verify WB) |
Important caveats
Reasons your observed band may differ from the expected size.
| PTM | Ubl conjugation | |
| Caveat | Modification-state controls | |
| Gene-set association | MSigDB Hallmark membership | |
| Isoform | 1 isoform(s) |
Section 1
Real Curated CRABP2 Western Blot Protocols
The A03297-3 protocol combines labelled catalog values with standard starting conditions. Published comparisons retain their own sample, reagent and detection scope.
| Sample / lysate | human MCF-7, human T-47D (catalog A03297-3) |
| Gel % | 5–20% (catalog A03297-3) |
| Load | 30 ug; reducing conditions (catalog A03297-3) |
| Transfer | a nitrocellulose membrane at 150 mA for 50-90 minutes (catalog A03297-3) |
| Membrane | nitrocellulose membrane (catalog A03297-3) |
| Blocking | 5% non-fat milk/TBS for 1.5 hour at RT (catalog A03297-3) |
| Primary antibody | A03297-3 · 0.5 μg/mL (catalog A03297-3) |
| Primary incubation | overnight at 4°C (catalog A03297-3) |
| Secondary antibody | goat anti-rabbit IgG-HRP, 1:5000 (catalog A03297-3) |
| Secondary incubation | 1.5 hour at RT (catalog A03297-3) |
| Wash | TBS-0.1%Tween 3 times with 5 minutes each (catalog A03297-3) |
| Detection | ECL (catalog A03297-3) |
Section 2
What Is the Expected CRABP2 Western Blot Band Size?
CRABP2 is predicted at 15.7 kDa and observed near 17 kDa; the cause of the difference is not established.
| Single band near 17 kDa | Matches the empirical CRABP2 band; confirm identity with controls |
| Single band near 15.7 kDa | Near the UniProt predicted mass; confirm identity with controls |
| Weak band near 17 kDa | Possible CRABP2 signal requiring identity controls |
| No band near 17 kDa | CRABP2 is not detected under these conditions |
💡Expected CRABP2 appearanceCRABP2 has a UniProt predicted mass of 15.7 kDa and an empirical band near 17 kDa; the cause of the difference is not established, so confirm identity with appropriate controls.
| UniProt predicted molecular weight | Places the calculated protein mass at 15.7 kDa |
| UniProt molecular weight in daltons | Gives the same calculated mass as 15,693 Da |
| 138 amino acid sequence | Defines the sequence used for the predicted mass |
| Predicted mass relative to observed migration | The 15.7 kDa prediction does not establish why the empirical band appears near 17 kDa |
| Situation | Likely cause | Next action |
|---|---|---|
| No band in lysate | CRABP2 may be below detection in the sampled lysate | Check loading and assay sensitivity with a positive control |
| Band higher than expected | The supplied features do not establish a size increasing mechanism | Compare with the 17 kDa QC band and verify identity with an independent antibody or knockdown |
| Band lower than expected | The supplied features do not establish cleavage | Check sample integrity and verify identity with an independent antibody or knockdown |
| Multiple bands | The additional bands have no established identity | Use an independent antibody or knockdown to identify the CRABP2 band |
| Weak or no signal | CRABP2 may be scarce in the sampled material | Check loading and test a positive control |
Experiment evidence
Western blot images showing CRABP2 band
A03297-3 · CRABP2
A30602 · CRABP2
A30602 · CRABP2
M03297-1 · CRABP2
← swipe / scroll for more images →
Real WB data behind the band-size expectations in this section.
Sample controls for CRABP2 Western blot
🧪HPA-IHC candidate guidance (verify in WB): For positive controls for CRABP2 in Western blot, you can use endometrium lysate, which HPA rates as highly expressed.
Positive control: Endometrium (IHC candidate; verify WB)
Negative control: Adipose tissue (IHC candidate; verify WB)
Loading controls: Run GAPDH, β-actin, and a total-protein stain alongside the samples.
⚠️Feasibility: A tissue contrast is feasible because HPA reports high expression in endometrium and no detection in adipose tissue.
HPA tissue expression evidence for CRABP2
Comprehensive Human Protein Atlas IHC scoring per tissue. Rows are taken directly from the HPA tissue chart — click any row's HPA link to view the source.
Higher expression tissues · candidate positive controls from IHC
| Tissue | Cell type | Level | Evidence | Source |
|---|---|---|---|---|
| Endometrium | macrophages | High | Protein (IHC) | HPA → |
| Esophagus | squamous epithelial cells | High | Protein (IHC) | HPA → |
| Skin | eccrine glands | High | Protein (IHC) | HPA → |
| Vagina | squamous epithelial cells | High | Protein (IHC) | HPA → |
| Breast | glandular cells | Medium | Protein (IHC) | HPA → |
Lower expression tissues · IHC evidence, not confirmed WB-negative controls
| Tissue | Cell type | Level | Evidence | Source |
|---|---|---|---|---|
| Adipose tissue | adipocytes | Not detected | Protein (IHC) | HPA → |
| Adrenal gland | glandular cells | Not detected | Protein (IHC) | HPA → |
| Appendix | glandular cells | Not detected | Protein (IHC) | HPA → |
| Bone marrow | hematopoietic cells | Not detected | Protein (IHC) | HPA → |
| Bronchus | respiratory epithelial cells | Not detected | Protein (IHC) | HPA → |
Section 3
Advanced CRABP2 Western Blot Tips
Deeper troubleshooting and optimisation questions for CRABP2, answered from its protein features.
How should CRABP2 band migration be interpreted?
Band shift · Use the separately labelled calculated mass and catalog-observed evidence above. A sequence annotation does not establish an observed migration shift. Verify target identity with orthogonal controls.
Could CRABP2 isoforms explain multiple bands?
Isoforms · The supplied entry lists one isoform and no alternative sequence. It does not support assigning additional bands to CRABP2 isoforms. Check whether those bands depend on CRABP2 before interpreting them.
Do listed modifications predict a CRABP2 band shift?
PTM · The entry has Ubl conjugation and isopeptide bond keywords, but lists no modified residues, glycosylation sites, or modification coordinates. Those keywords alone do not predict a visible shift or explain the approximately 17 kDa band.
Does this guide establish induction of CRABP2?
Induction · No general induction response is established by this guide. A pathway or gene-set association is not evidence of induction in a particular specimen. Verify the relevant treatment and control in a target-specific experiment.
What transfer method to use for CRABP2 Western blot?
Transfer · For this predicted 15.7 kDa protein, start with a controlled, short wet transfer and check both the membrane and post-transfer gel. Adjust transfer time if CRABP2 remains in the gel or passes through the membrane.
How should blocking be optimized?
Blocking · Standard workflow guidance: follow the A03297-3 datasheet where specified. Otherwise compare 5% milk or 5% BSA in TBST; for a phospho-specific assay start with BSA. Optimize background and specific signal with matched controls.
How should CRABP2 be quantified after ligand treatment?
Quantitation · Quantify total lysate and nuclear or cytoplasmic fractions separately, with appropriate loading normalization for each. Ligand-dependent nuclear transport can change fraction signals without establishing a change in total protein abundance.
Why is CRABP2 near 17 kDa despite a 15.7 kDa prediction?
Interpretation · The supplied observed band is approximately 17 kDa, close to the predicted 15.7 kDa. The listed features do not establish a cause for the difference. Identify the band by antibody specificity and its behavior across samples, not mass alone.
Upon ligand binding, CRABP2 exposes a nuclear localization motif and moves into the nucleus. Compare nuclear and cytoplasmic fractions when assessing ligand effects; a change in one fraction need not indicate a change in total CRABP2 abundance.
The entry notes Ubl conjugation and interactions with RXR, RARA, and importin alpha, but does not establish that any causes a higher Western-blot band. Test band specificity, for example by CRABP2 depletion, before assigning a band to a conjugate or complex.
Upon ligand binding, CRABP2 exposes a nuclear localization motif and moves into the nucleus. Compare nuclear and cytoplasmic fractions when assessing ligand effects; a change in one fraction need not indicate a change in total CRABP2 abundance.
The entry notes Ubl conjugation and interactions with RXR, RARA, and importin alpha, but does not establish that any causes a higher Western-blot band. Test band specificity, for example by CRABP2 depletion, before assigning a band to a conjugate or complex.
Boster reagents
CRABP2 Western Blot Antibodies
Catalog antibodies with Western blot application and product-specific WB images. Evaluate suitability with the reported sample, controls and experimental conditions.
Real WB data
Anti-CRABP2 Antibody Picoband®
Cat # A03297-3
Real WB data
Anti-CRABP2 Antibody
Cat # A30602
Real WB data
Anti-CRABP2 Rabbit Monoclonal Antibody
Cat # M03297-1
Three anti-CRABP2 antibodies have WB images. A03297-3 shows an approximately 17 kDa band in human MCF-7 and T-47D lysates with reported conditions. M03297-1 shows MCF7 and mouse skin lysates; A30602’s caption gives no specific samples or conditions.
Which to pick: Choose A03297-3 for a human lysate protocol with detailed WB conditions. M03297-1 has reported MCF7 and mouse skin examples. A30602 lists human, mouse and rat reactivity, but its WB caption does not identify samples; rat WB evidence is not specified for these antibodies.
Source: BosterBio CRABP2 gene-info card — filtered to Western-blot-capable antibodies; each card shows that product's actual WB validation figure.
References
- UniProt Consortium. UniProt entry P29373.
- Human Protein Atlas. CRABP2 tissue expression.
- PMC8973949 — target-verified WB comparison
- PMC10765133 — target-verified WB comparison
- PMC13576788 — target-verified WB comparison