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U2AF2 / Splicing factor U2AF 65 kDa subunit · IHC design guide
Design Immunohistochemistry for U2AF2
Plan paraffin IHC for U2AF2 around widespread nuclear staining (HPA tissue IHC). Compare high-staining glandular cells with low-staining glia or myocytes (HPA tissue IHC), and keep fixation consistent across sections.
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
U2AF2 Immunohistochemistry Experimental Design Guide
Expected localisation, validated protocols, controls and antibodies — the at-a-glance facts below, then the full design guide.
Must know before staining
| Expected localisation | Nuclear staining in tissue (HPA tissue IHC) | |
| Staining pattern | Widespread nuclear staining; high in glandular cells (HPA tissue IHC) | |
| Antigen retrieval | EDTA pH 8.0 HIER, heat-mediated (datasheet M03639-1) | |
| Positive control | Adrenal gland+4 more · see all | |
| Negative control | None in HPA (detected in all 45 tissues); use no-primary + isotype controls |
Important caveats
Reasons your staining may differ from the expected pattern.
| Fixation | Keep fixation consistent across sections (standard IHC practice; not target-specific); Matched tissue-IHC evidence does not establish the fixation claim. Validate the specimen-specific method before use. (selected-SKU IHC image M03639-1) | |
| Caveat | Intensity varies by cell type despite broad expression (HPA tissue IHC) | |
| Regulation | No specific expression regulator annotated (UniProt) | |
| Isoform / epitope | 2 isoforms; antibody epitope coverage is unknown (UniProt) |
Section 1
Recommended U2AF2 IHC & IF Protocols
Compare the catalog antibody’s IHC-P protocol with the published mouse aortic tissue IHC protocol (PMC12924209: histological staining).
| Sample | Paraffin-embedded human gallbladder adenocarcinoma tissue; fixative not specified (datasheet M03639-1) |
| Fixation | Image fixative and duration unreported (datasheet M03639-1); verify before use. |
| Sectioning | 4–5 µm sections on charged slides (standard) |
| Deparaffinisation | Xylene, graded ethanol series to water (standard) |
| Antigen retrieval | Heat retrieval: EDTA pH 8.0 (datasheet M03639-1); 20 min, 95–100 °C (standard) |
| Peroxidase block | 3% H2O2, 10 min, room temperature (standard) |
| Blocking | 10% goat serum (datasheet M03639-1) |
| Primary antibody | Mouse monoclonal (clone 3G9) anti-U2AF2, 2μg/ml (datasheet M03639-1) |
| Primary incubation | Overnight at 4 °C (datasheet M03639-1) |
| Detection | Streptavidin-biotin complex (SABC), DAB chromogen (datasheet M03639-1) |
| Counterstain | Hematoxylin, blue, dehydrate and mount (standard) |
| Expected result | U2AF2-positive staining in glandular cells of adrenal gland (HPA tissue IHC: High). HPA tissue profile: Ubiquitous nuclear expression. No signal in the no-primary control. |
💡Decision noteStart with heat-mediated EDTA pH 8.0 retrieval (datasheet: M03639-1); the published protocol does not specify its retrieval solution’s composition or pH (PMC12924209: histological staining).
Section 2
What Is the Expected U2AF2 Staining Pattern?
U2AF2 should stain nuclei across many cell types: UniProt places it in the nucleus and reports no transmembrane segment (UniProt P26368). In paraffin tissue, HPA describes ubiquitous nuclear expression, with high staining in several glandular cell populations, kidney tubule cells, and lymph node germinal center cells (HPA tissue IHC). HPA rates the tissue pattern Supported, with medium consistency between antibody staining and RNA expression (HPA tissue IHC).
| Nuclear chromogen appears in glandular cells of colon or duodenum, or in kidney tubule cells. | This matches high staining reported for those cells and the expected nuclear compartment (HPA tissue IHC; UniProt P26368). Compare nuclei within the same section before scoring intensity: HPA levels describe observed patterns, not a required intensity for every cell or specimen (HPA tissue IHC). |
| Cytoplasmic or membranous staining dominates while nuclei are weak or unstained. | Treat this as a localisation mismatch: U2AF2 is nuclear and has no transmembrane segment (UniProt P26368). Review counterstained nuclei, the negative reagent control, and detection background before interpreting the extranuclear colour as U2AF2 (general IHC practice). |
| Strong staining is confined to a population reported as low, while expected positive cells are unstained. | HPA reports low staining in skeletal myocytes, smooth muscle cells, breast adipocytes, and some glial cells (HPA tissue IHC). This reversal raises cross-reactivity or endogenous detection activity as possibilities; an HPA low designation alone does not make every stained cell a false positive (HPA tissue IHC; general IHC practice). |
| Colour spreads across extracellular space, section edges, or many compartments without clear nuclear boundaries. | Diffuse colour cannot be scored confidently as the nuclear U2AF2 pattern (UniProt P26368; general IHC practice). Check reagent-only controls and blocking, washing, and detection steps for nonspecific background (general IHC practice). |
| No nuclear staining appears in a known-positive control section. | Colon or duodenum glandular cells and kidney tubule cells are reported High by HPA (HPA tissue IHC). An unstained control makes a negative study section inconclusive; first check section integrity, antibody and detection steps, and control staining (general IHC practice). |
💡Expected U2AF2 appearanceCall a result positive when cell nuclei show clear chromogen, especially in HPA High populations such as colon glandular cells; diffuse extranuclear colour without nuclear definition is suspect (HPA tissue IHC; UniProt P26368; general IHC practice).
| Nuclear localisation and topology | UniProt assigns U2AF2 to the nucleus and reports no transmembrane segment (UniProt P26368). Score chromogen against counterstained nuclei; a surface or membrane pattern does not fit that annotation (general IHC practice; UniProt P26368). |
| Choice of tissue control | HPA reports High staining in adrenal, colon, duodenum, epididymis, fallopian tube, and gallbladder glandular cells, kidney tubule cells, and lymph node germinal center cells (HPA tissue IHC). Low-staining populations are weaker comparators, not verified negative controls (HPA tissue IHC). |
| Antibody evidence | HPA marks HPA043562 and CAB010910 Supported for IHC; HPA041943 has ICC support but no supplied IHC status (HPA antibody records). Interpret a new antibody's staining with its own controls rather than transferring that validation to it (general IHC practice). |
| Isoforms and epitope coverage | UniProt lists two U2AF2 isoforms and three RNA recognition motifs (UniProt P26368). The payload gives no antibody epitope or isoform coverage, so these annotations cannot predict which isoform a stain detects or explain a negative section. |
| IF/ICC Q: What localisation should be expected? | HPA reports supported nucleoplasmic and nuclear speckle localisation, with a cytokinetic bridge as an additional location (HPA subcellular ICC-IF). Those ICC-IF observations help interpret fluorescence images; they do not establish an IHC chromogen pattern in every tissue (HPA subcellular ICC-IF; HPA tissue IHC). |
| Situation | Likely cause | Next action |
|---|---|---|
| Positive-control nuclei are blank. | A failed staining or detection step is possible; HPA reports High staining in colon glandular and kidney tubule cells (HPA tissue IHC). | Verify that the control section and detection reagents worked, then review antibody dilution and retrieval against the antibody's IHC instructions (general IHC practice). Do not score study negatives until the control stains. |
| The section has strong cytoplasmic colour but little nuclear colour. | The dominant signal conflicts with nuclear U2AF2 localisation (UniProt P26368). Nonspecific binding or detection background may contribute (general IHC practice). | Compare with a negative reagent control, inspect counterstained nuclei, and reassess blocking and washing (general IHC practice). |
| Brown colour is widespread and obscures cell boundaries. | Diffuse detection background can hide a nuclear pattern (general IHC practice). | Check reagent-only controls and review antibody dilution, blocking, washing, and detection conditions one at a time (general IHC practice). Score only nuclei that remain distinguishable. |
| A low-staining cell population appears stronger than the chosen positive control. | HPA reports Low staining in populations including skeletal myocytes and some glial cells, but that designation is not absolute absence (HPA tissue IHC). | Confirm cell identity and compare staining with an HPA High control; investigate cross-reactivity or endogenous detection activity using appropriate controls (HPA tissue IHC; general IHC practice). |
| An ICC-supported antibody gives an uncertain paraffin-section result. | HPA041943 is Supported for ICC, with no supplied IHC status; ICC support does not establish IHC performance (HPA antibody records). | Use an IHC-validated antibody and a positive tissue control to assess the paraffin-section result (HPA antibody records; HPA tissue IHC; general IHC practice). |
| Nuclear intensity varies between tissue populations. | HPA reports ubiquitous nuclear expression alongside High and Low cell-specific levels, with medium consistency between staining and RNA data (HPA tissue IHC). | Record the cell population and nuclear intensity separately. Compare each with its HPA tissue entry and an internal control before calling variation a technical failure (HPA tissue IHC; general IHC practice). |
Experiment evidence
IHC & IF images showing U2AF2 staining
M03639-1 · IHCIHC analysis of U2AF65/U2AF2 using anti U2AF65/U2AF2 antibody (M03639-1). U2AF65/U2AF2 was detected in paraffin-embedded section of human ga
M03639-1 · IHCIHC analysis of U2AF65/U2AF2 using anti U2AF65/U2AF2 antibody (M03639-1). U2AF65/U2AF2 was detected in paraffin-embedded section of human ma
M03639-1 · IFIF analysis of U2AF65/U2AF2 using anti-U2AF65/U2AF2 antibody (M03639-1). U2AF65/U2AF2 was detected in immunocytochemical section of A549 cel
M03639 · IHCIHC analysis of U2AF65/U2AF2 using anti U2AF65/U2AF2 antibody (M03639). U2AF65/U2AF2 was detected in paraffin-embedded section of human gall
M03639 · IHCIHC analysis of U2AF65/U2AF2 using anti U2AF65/U2AF2 antibody (M03639). U2AF65/U2AF2 was detected in paraffin-embedded section of human adne
M03639 · IFIF analysis of U2AF65/U2AF2 using anti-U2AF65/U2AF2 antibody (M03639). U2AF65/U2AF2 was detected in immunocytochemical section of A549 cells
A03639-2 · IHCIHC analysis of U2AF2 using anti-U2AF2 antibody (A03639-2). U2AF2 was detected in paraffin-embedded section of human mammary cancer tissue.
A03639-2 · IHCIHC analysis of U2AF2 using anti-U2AF2 antibody (A03639-2). U2AF2 was detected in paraffin-embedded section of mouse spleen tissue. Heat med
A03639-2 · IFIF analysis of U2AF2 using anti-U2AF2 antibody (A03639-2). U2AF2 was detected in immunocytochemical section of Hela cells. Enzyme antigen re
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000063244-U2AF2/tissue/cerebral+cortex#imid_15510667
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000063244-U2AF2/tissue/colon#imid_15510585
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000063244-U2AF2/tissue/liver#imid_15510578
HPA · KidneyHuman Protein Atlas IHC, Kidney. Source: https://www.proteinatlas.org/ENSG00000063244-U2AF2/tissue/kidney#imid_15510579
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody CAB010910; green = U2AF2, blue = nucleus, red = microtubules.
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody CAB010910; green = U2AF2, blue = nucleus, red = microtubules.
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for U2AF2 IHC & IF
🧪Run colon first: its glandular cells should stain (HPA: High in colon glandular cells), with predominantly nuclear signal (UniProt P26368: nucleus). HPA detects U2AF2 in all 45 scored tissues, so there is no supported negative tissue; use no-primary and isotype controls, and do not assume any cells on the positive slide are true internal negatives (HPA: detected in all 45 scored tissues).
Positive control tissue: Adrenal gland (Glandular cells, HPA High)
Negative control tissue: None in HPA: U2AF2 is detected in all 45 scored tissues. Use a no-primary (secondary-only) and an isotype control instead.
ICC-IF cell lines (HPA subcellular resource): HPA ICC-IF images show U2AF2 in A-431, U-251MG, U2OS, HEK293, MCF-7, NIH 3T3, with annotated localisation: Nucleoplasm (supported), Nuclear speckles (supported) (HPA subcellular).
Technical controls: Include a no-primary, secondary-only slide and a concentration-matched mouse IgG isotype control; use a U2AF2 knockout specimen or, if the immunizing peptide is available, a peptide-blocked antibody as a biological specificity check (caption: mouse primary antibody; standard IHC practice). For chromogenic detection, control endogenous peroxidase and assess endogenous biotin background because the caption uses a biotin-based detection system (caption: biotinylated secondary and SABC–DAB).
⚠️Feasibility: No target-specific fixation window or fixation effect is reported, and the selected M03639-1 tissue-IHC caption does not state its fixative (caption: fixative unreported). The demonstrated paraffin-section workflow uses heat-mediated retrieval in EDTA at pH 8.0; retrieval dependence beyond that workflow is unreported (caption: EDTA heat retrieval). HPA shows nucleoplasmic and nuclear-speckle ICC-IF localisation, but the supplied evidence does not establish that frozen sections or IF are easier than paraffin IHC; in colon, assess background from the biotin-based chromogenic workflow (HPA: subcellular ICC-IF; caption: SABC–DAB).
HPA tissue IHC evidence for U2AF2
Comprehensive Human Protein Atlas IHC scoring per tissue (reliability: Supported — Medium consistency between antibody staining and RNA expression data.). Rows are taken directly from the HPA tissue chart — click any row's HPA link to view the source.
Positive expression · recommended positive controls
| Tissue | Cell type | Level | Evidence | Source |
|---|---|---|---|---|
| Adrenal gland | Glandular cells | High | Protein (IHC) | HPA → |
| Colon | Glandular cells | High | Protein (IHC) | HPA → |
| Duodenum | Glandular cells | High | Protein (IHC) | HPA → |
| Epididymis | Glandular cells | High | Protein (IHC) | HPA → |
| Fallopian tube | Glandular cells | High | Protein (IHC) | HPA → |
Undetected expression · recommended negative controls
| Tissue | Cell type | Level | Evidence | Source |
|---|---|---|---|---|
| None in HPA: U2AF2 is detected in all 45 scored tissues. Use a no-primary (secondary-only) and an isotype control instead. | ||||
Section 3
Advanced U2AF2 IHC Tips
Troubleshoot chromogenic U2AF2 IHC by checking nuclear staining, section processing, controls, and scoring against the supplied tissue evidence.
What retrieval conditions should I start with for weak U2AF2 staining?
Start with heat-mediated antigen retrieval in EDTA at pH 8.0 for paraffin sections (datasheet M03639-1). The reported tissue image used this retrieval before overnight incubation at 4°C with 2 µg/mL primary antibody, so keep those conditions together for the first comparison (datasheet M03639-1). If nuclear signal is weak, compare a modestly longer heating interval with the original interval while holding section thickness, cooling, antibody concentration, and detection constant (standard IHC practice). Judge improvement by nuclear staining and preserved tissue morphology, using the same positive-control tissue across runs (UniProt P26368; HPA tissue IHC; standard IHC practice).
Could fixation explain weak or uneven nuclear staining?
Target-specific fixation sensitivity is unknown: the selected paraffin-section caption does not state a fixative, and the HPA staining profile supplies no fixation comparison (datasheet M03639-1; HPA tissue IHC). Record each specimen's fixative, fixation duration, tissue size, and processing history before comparing staining intensity (standard IHC practice). When troubleshooting, process matched sections together and vary only a known fixation or retrieval condition at a time, checking nuclear detail and tissue integrity (standard IHC practice; UniProt P26368). Do not infer a U2AF2-specific fixation effect from its nuclear localisation, RNA-binding domains, or annotated modifications (UniProt P26368).
Where should convincing U2AF2 staining appear in paraffin sections?
Expect predominantly nuclear chromogenic staining because U2AF2 is annotated as nuclear and HPA describes ubiquitous nuclear tissue expression (UniProt P26368; HPA tissue IHC). HPA cell imaging places it in the nucleoplasm and nuclear speckles, but chromogenic tissue sections may not resolve a speckled pattern reliably (HPA subcellular; standard IHC practice). Compare nuclei within intact, well-preserved cells and check a positive reference such as gallbladder glandular cells or kidney tubular cells, both reported with high staining (HPA tissue IHC). Predominantly cytoplasmic or extracellular colour warrants review of background, morphology, and controls before assigning it to U2AF2 (UniProt P26368; standard IHC practice).
How do isoforms or modifications affect epitope interpretation?
U2AF2 has 2 annotated isoforms and 3 RNA recognition motifs spanning residues 149–231, 259–337, and 385–466 (UniProt P26368). Its record also lists modified residues, including phosphorylation, acetylation, and hydroxylation, but the supplied tissue caption does not identify the antibody epitope (UniProt P26368; datasheet M03639-1). Therefore, staining differences cannot establish which isoform or modification is present without independent epitope mapping and appropriate validation controls (standard IHC practice). If two antibodies give different nuclear patterns, compare their documented epitopes, retrieval conditions, and matched-section controls before proposing a biological explanation (UniProt P26368; standard IHC practice).
How should I investigate U2AF2 localisation by multiplex IF?
For a separate IF experiment, pair U2AF2 with a validated marker for the cell population being assessed, and use a nuclear counterstain to identify individual nuclei (HPA tissue IHC; standard IF practice). Select fluorophores after inspecting unstained tissue autofluorescence, favouring a well-separated channel with low background for the U2AF2 signal (standard IF practice). Because U2AF2 is nuclear and has no annotated transmembrane segment, optimise permeabilisation to admit antibody to the nucleus while preserving nuclear morphology (UniProt P26368; standard IF practice). Assess nucleoplasmic signal and possible nuclear speckles against single-stain and secondary-only controls, without treating IF settings as validated IHC conditions (HPA subcellular; standard IF practice).
What should I check when DAB obscures nuclear signal?
Check whether diffuse brown colour persists in a no-primary control, then inspect peroxidase blocking, secondary-antibody background, and DAB development time (standard IHC practice). The selected tissue image used a biotinylated secondary antibody, streptavidin-biotin detection, and DAB, so include a control that can reveal background from that detection chain (datasheet M03639-1; standard IHC practice). Compare sections with matched counterstaining and examine tissue edges, folds, and damaged regions before adjusting primary-antibody concentration (standard IHC practice). Preserve interpretable nuclei as the endpoint: U2AF2 is nuclear, while HPA reports ubiquitous nuclear tissue staining rather than a clean negative tissue (UniProt P26368; HPA tissue IHC).
How should I score U2AF2 across sections with different cellularity? ⚠ ANSWER MARKED FOR VERIFICATION
Define the cell population and score nuclear DAB signal as percentage positive plus intensity, or combine them in a prespecified H-score (UniProt P26368; standard IHC practice). Use consistent positivity thresholds, magnification, and sampled area across matched sections; record the number of assessable nuclei for each region (standard IHC practice). Normalise positive counts to total assessable nuclei of the same cell population, or report positive nuclei per mm² alongside cellular density when area-based sampling is needed (standard IHC practice). Analyse glandular, tubular, and other compartments separately where relevant, since HPA reports differing cell-level staining across tissues (HPA tissue IHC).
How can I distinguish true U2AF2 staining from artefact?
A credible result shows signal in intact nuclei, consistent with U2AF2's nuclear annotation and HPA's ubiquitous nuclear tissue profile (UniProt P26368; HPA tissue IHC). Compare the pattern with a positive reference: HPA reports high staining in gallbladder glandular cells and kidney tubular cells, while its tissue-IHC reliability is rated Supported (HPA tissue IHC). Treat staining restricted to tissue edges, folds, or necrotic areas as suspect, and investigate diffuse cytoplasmic colour or no-primary-control signal before calling it positive (standard IHC practice; UniProt P26368). Check endogenous peroxidase and detection-chain background when DAB appears outside preserved nuclei (datasheet M03639-1; standard IHC practice).
Boster reagents
Best U2AF2 / Splicing factor U2AF 65 kDa subunit IHC Antibodies
Catalog anti-U2AF2 antibodies have paraffin-section IHC images from human tumors and mouse and rat spleen (catalog IHC captions), plus IF/ICC images from A549 and HeLa cells (catalog IF captions).
Real IHC data
Anti-U2AF65/U2AF2 ® Antibody (monoclonal, 3G9)
Cat # M03639-1
Real IHC data
Anti-U2AF65/U2AF2 ® Antibody (monoclonal, 10F4)
Cat # M03639
Real IHC data
Anti-U2AF65/U2AF2 Antibody ®
Cat # A03639-2
M03639-1 (clone 3G9) and M03639 (clone 10F4) each have paraffin-section IHC images from human gallbladder adenocarcinoma and IF/ICC images from A549 cells (catalog entries and image captions). A03639-2 has paraffin-section IHC images from human mammary cancer and mouse and rat spleen, plus an IF/ICC image from HeLa cells (A03639-2 image captions).
Which to pick: For tissue IHC, choose M03639-1 if a mouse monoclonal is preferred: clone 3G9 is listed for IHC, and its own image shows human gallbladder adenocarcinoma paraffin sections (M03639-1 catalog entry and IHC caption). For IF/ICC, A03639-2 has a documented 2 μg/ml HeLa cell example (A03639-2 IF caption). For IHC across the listed species, A03639-2 has separate human, mouse and rat paraffin-section images (A03639-2 IHC captions); the fixative is unreported in those captions (A03639-2 IHC captions).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry P26368 (U2AF2_HUMAN, Splicing factor U2AF 65 kDa subunit).
- Human Protein Atlas. U2AF2 tissue IHC expression (reliability: Supported).
- Human Protein Atlas. U2AF2 subcellular location (ICC-IF): Localized to the nucleoplasm and nuclear speckles..
- Human Protein Atlas. U2AF2 antibody validation summary (3 antibodies).
- Vascular smooth muscle cell RNA-binding protein U2AF2 induces copper death by regulating C1qbp expression, delaying development of atherosclerosise. Biological research 2026 — PMC12924209.
- The U2AF2 /circRNA ARF1/miR-342-3p/ISL2 feedback loop regulates angiogenesis in glioma stem cells. Journal of experimental & clinical cancer research : CR 2020 — PMC7487667.
- CD82 suppresses CD44 alternative splicing-dependent melanoma metastasis by mediating U2AF2 ubiquitination and degradation. Oncogene 2016 — PMC5033661.
- OTUB2-mediated deubiquitination upregulates U2AF2 to promote colorectal cancer evasion of autophagy-ferroptosis. Cell death & disease 2026 — PMC13319764.
- PubMed PMID:1538748 — UniProt-cited evidence.
- PubMed PMID:15489334 — UniProt-cited evidence.
- PubMed PMID:12176931 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for U2AF2 (Splicing factor U2AF 65 kDa subunit). Expected localisation Nuclear staining in tissue (HPA tissue IHC). Antigen retrieval: EDTA pH 8.0 HIER, heat-mediated (datasheet M03639-1). Validated IHC antibody: M03639-1 at 2μg/ml (the product's own IHC validation image is shown). Controls (HPA): positive Adrenal gland (Glandular cells); negative None in HPA (detected in all 45 tissues); use no-primary + isotype controls. IHC-P workflow on paraffin sections; fixative unspecified. Protocol steps: 1. Sample: Paraffin-embedded human gallbladder adenocarcinoma tissue; fixative not specified (datasheet M03639-1); 2. Fixation: Image fixative and duration unreported (datasheet M03639-1); verify before use.; 3. Sectioning: 4–5 µm sections on charged slides (standard); 4. Deparaffinisation: Xylene, graded ethanol series to water (standard); 5. Antigen retrieval: Heat retrieval: EDTA pH 8.0 (datasheet M03639-1); 20 min, 95–100 °C (standard); 6. Peroxidase block: 3% H2O2, 10 min , room temperature (standard); 7. Blocking: 10% goat serum (datasheet M03639-1); 8. Primary antibody: Mouse monoclonal (clone 3G9) anti-U2AF2, 2μg/ml (datasheet M03639-1); 9. Primary incubation: Overnight at 4 °C (datasheet M03639-1). Watch for: Fixation: Keep fixation consistent across sections (standard IHC practice; not target-specific); Matched tissue-IHC evidence does not establish the fixation claim. Validate the specimen-specific method before use. (selected-SKU IHC image M03639-1); Caveat: Intensity varies by cell type despite broad expression (HPA tissue IHC); Isoform / epitope: 2 isoforms; antibody epitope coverage is unknown (UniProt); Regulation: No specific expression regulator annotated (UniProt). Evidence: UniProt P26368, HPA tissue IHC · Supported, HPA ICC-IF · nucleoplasm and nuclear speckles., Datasheet M03639-1, PMC12924209. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/U2AF2/immunohistochemistry-ihc-guide.