This website uses cookies to ensure you get the best experience on our website.
- Table of Contents
EMX2 / Homeobox protein EMX2 · IHC design guide
Design Immunohistochemistry for EMX2
Plan chromogenic IHC-P for EMX2 using its mainly nuclear tissue staining pattern (HPA tissue IHC). This guide covers tissue controls, compartment-aware scoring and an IHC-validated antibody with a starting concentration of 2.5 μg/mL (datasheet: A04322-1).
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
EMX2 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 | Mainly nuclear in tissues (HPA tissue IHC); also axonal (UniProt) | |
| Staining pattern | Mainly nuclear staining in several tissues (HPA tissue IHC) | |
| Antigen retrieval | Tris-EDTA pH 9.0 HIER, 95–98 °C, 20 min (rule: nuclear antigen) | |
| Positive control | Cerebellum+4 more · see all | |
| Negative control | Adipose tissue+4 more · see all |
Important caveats
Reasons your staining may differ from the expected pattern.
| Fixation | Keep fixation consistent across paraffin sections. (standard IHC practice; not target-specific) | |
| Caveat | Cerebellar GLUC cells show cytoplasm/membrane staining (HPA tissue IHC) | |
| Regulation | Expression varies by tissue (HPA tissue IHC) | |
| Isoform / epitope | 2 isoforms; shared epitope status is unknown (UniProt) |
Section 1
Recommended EMX2 IHC & IF Protocols
Compare the catalog antibody’s IHC-P protocol with published EMX2 staining protocols for colorectal tissue, lung tissue, and cryosections (PMC5568393; PMC3285542; PMC11062917).
| Sample | Tissue sections; selected-image fixative not specified (standard IHC workflow) |
| Fixation | Image fixative and duration unreported (datasheet A04322); verify before use. |
| Sectioning | 4–5 µm sections on charged slides (standard) |
| Deparaffinisation | Xylene, graded ethanol series to water (standard) |
| Antigen retrieval | Heat-induced epitope retrieval in Tris-EDTA buffer, pH 9.0, 20 min at 95–98 °C (standard rule: nuclear antigen) |
| Peroxidase block | 3% H2O2, 10 min, room temperature (standard) |
| Blocking | 10% normal serum of the secondary host, 30 min, room temperature (standard) |
| Primary antibody | Rabbit anti-EMX2, 5 μg/mL (datasheet A04322) |
| Primary incubation | Overnight at 4 °C (standard) |
| Detection | HRP-polymer secondary, DAB chromogen 5–10 min (standard) |
| Counterstain | Hematoxylin, blue, dehydrate and mount (standard) |
| Expected result | EMX2-positive staining in gLUC cells - cytoplasm/membrane of cerebellum (HPA tissue IHC: Medium). HPA tissue profile: Mainly nuclear expression in several tissues. No signal in the no-primary control. |
💡Decision noteStart with Tris-EDTA pH 9.0 HIER at 95–98 °C for 20 min (page antigen retrieval); citrate heat retrieval was used for lung sections (PMC3285542).
Section 2
What Is the Expected EMX2 Staining Pattern?
EMX2 is primarily a nuclear protein (UniProt Q04743; HPA tissue IHC). In paraffin sections, look for staining in the specific cells HPA reports, including epididymal glandular cells, kidney collecting ducts and ovarian follicle cells (HPA tissue IHC). HPA rates tissue staining reliability Enhanced, with medium consistency between staining and RNA data (HPA tissue IHC). EMX2 has no transmembrane segment (UniProt Q04743 topology).
| Nuclear staining in epididymal glandular cells, kidney collecting ducts or ovarian follicle cells. | This fits the predominant EMX2 pattern; HPA reports Medium staining in each of these cell populations (HPA tissue IHC). Compare positive cells with adjacent structures rather than scoring a whole tissue as uniformly positive (general IHC practice). |
| Broad cytoplasmic or membrane staining replaces nuclear staining across a section. | Treat this as a possible artefact because the overall tissue pattern is mainly nuclear (HPA tissue IHC). Check context before rejecting it: HPA reports cytoplasm/membrane staining in cerebellar GLUC cells, while UniProt reports EMX2 in olfactory axons (HPA tissue IHC; UniProt Q04743). |
| Strong staining appears in an HPA-listed negative cell population, such as adipocytes in adipose tissue. | HPA reports EMX2 as Not detected in those adipocytes (HPA tissue IHC). Consider antibody cross-reactivity or endogenous detection activity; inspect the no-primary control and whether signal follows the expected cell boundaries (general IHC practice). |
| Diffuse colour covers both cells and surrounding tissue, obscuring nuclei. | This is background rather than an interpretable compartment pattern (general IHC practice). Review the no-primary control, blocking, wash steps and chromogen development before assigning EMX2 positivity; HPA's mainly nuclear pattern cannot validate diffuse staining (HPA tissue IHC). |
| No signal appears in a section containing HPA-listed Medium-positive cells. | A negative run is inconclusive until the detection system and tissue quality are checked (general IHC practice). Confirm that the relevant cell population is present, then review the IHC antibody dilution and antigen-retrieval conditions; HPA's reported Medium level is a reference pattern, not a guarantee for every preparation (HPA tissue IHC). |
💡Expected EMX2 appearanceA convincing positive is cell-selective, mainly nuclear staining in an HPA-listed population such as kidney collecting ducts at the reported Medium level; widespread staining of HPA-listed negative cells is suspect (HPA tissue IHC).
| Compartment and anatomical context | HPA describes mainly nuclear tissue expression and approved nucleoplasmic ICC-IF localisation; its cerebellar GLUC-cell observation and UniProt's olfactory-axon report are context-specific exceptions (HPA tissue IHC; HPA subcellular; UniProt Q04743). |
| Choice of reference cells | HPA reports Medium staining in epididymal glandular cells, kidney collecting ducts and ovarian follicle cells, but Low staining in cerebral-cortex neurons; use the stated cell population and level when judging a slide (HPA tissue IHC). |
| Antibody evidence | HPA lists HPA065294 as IHC Enhanced and ICC Approved, and HPA003497 as IHC Supported; these are antibody-specific validation statuses, so assess the antibody actually used (HPA antibodies). |
| RNA and protein agreement | HPA calls tissue IHC reliability Enhanced yet describes only medium consistency with RNA expression. Cervix has tissue-enhanced RNA specificity while its glandular cells are Not detected by IHC; do not substitute RNA for a slide-level positive control (HPA tissue IHC). |
| Protein form | UniProt records two EMX2 isoforms, no signal peptide or propeptide, and one chain spanning residues 1–252. Without antibody epitope data, these facts cannot establish isoform coverage or a required antigen-retrieval condition (UniProt Q04743). |
| Situation | Likely cause | Next action |
|---|---|---|
| Nuclei are clear but most EMX2 signal is cytoplasmic. | The compartment disagrees with the mainly nuclear tissue pattern and approved nucleoplasmic ICC-IF localisation (HPA tissue IHC; HPA subcellular). | Check a no-primary control and review detection background; identify the stained cells before judging an exception, since cerebellar GLUC cells show cytoplasm/membrane staining (general IHC practice; HPA tissue IHC). |
| Unexpected cells stain more strongly than the intended positive population. | Cross-reactivity or endogenous detection activity is possible (general IHC practice); HPA reports some cell populations as Not detected (HPA tissue IHC). | Compare cell identity with HPA's cell-level reference, then use a no-primary control and appropriate endogenous-activity control for the detection chemistry (HPA tissue IHC; general IHC practice). |
| The section has diffuse brown background. | Nonspecific binding, incomplete washing or detection activity may obscure localisation (general IHC practice). | Review blocking and washes, inspect the no-primary control, and limit chromogen development as appropriate; score EMX2 only where cell and compartment boundaries remain readable (general IHC practice). |
| A section expected to contain Medium-positive cells has no signal. | The expected cells may be absent, or the staining workflow may have failed; HPA documents Medium staining only in specified cell populations (HPA tissue IHC). | Confirm the target cells on the counterstain, verify detection controls, and review the antibody's IHC dilution and antigen-retrieval instructions (general IHC practice). |
| Cerebral-cortex neurons look weak or negative beside a stronger control. | HPA reports Low staining in cerebral-cortex neurons, despite listing cerebral cortex as a tissue specificity in UniProt (HPA tissue IHC; UniProt Q04743). | Avoid using cortical neurons alone to declare a failed run; compare with an HPA-listed Medium-positive cell population under the same scoring criteria (HPA tissue IHC; general IHC practice). |
| Q: Should IF/ICC show the same compartment pattern? | HPA approves nucleoplasmic ICC-IF localisation for EMX2, while tissue IHC is mainly nuclear (HPA subcellular; HPA tissue IHC). | A: Expect a nucleoplasmic IF/ICC pattern where EMX2 is detected; interpret IF/ICC using its separate guide and assay controls (HPA subcellular; general IF practice). |
Experiment evidence
IHC & IF images showing EMX2 staining
A04322 · IHCImmunohistochemistry of EMX2 in human prostate tissue with EMX2 antibody at 5 μg/mL.
A04322-1 · IHCImmunohistochemistry of EMX2 in human lung tissue with EMX2 antibody at 2.5 μg/mL.
A04322-1 · IFImmunofluorescence of EMX2 in human lung tissue with EMX2 antibody at 20 μg/mL.
A04322-2 · IHCImmunohistochemistry validation of EMX2 using Anti-Homeobox protein EMX2 Emx2 Antibody (A04322-2). Immunohistochemical analysis of paraffin-
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000170370-EMX2/tissue/cerebral+cortex#imid_17957343
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000170370-EMX2/tissue/colon#imid_17957269
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000170370-EMX2/tissue/liver#imid_17957254
HPA · KidneyHuman Protein Atlas IHC, Kidney. Source: https://www.proteinatlas.org/ENSG00000170370-EMX2/tissue/kidney#imid_17957271
HPA · ICC-IF EFO-21Human Protein Atlas immunofluorescence, EFO-21, antibody HPA065294; green = EMX2, blue = nucleus, red = microtubules.
HPA · ICC-IF EFO-21Human Protein Atlas immunofluorescence, EFO-21, antibody HPA065294; green = EMX2, blue = nucleus, red = microtubules.
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for EMX2 IHC & IF
🧪Run kidney first: collecting-duct cells should stain at a Medium level (HPA: Kidney, collecting ducts, Medium). Use adipose tissue as the negative, with adipocytes showing no detectable staining (HPA: Adipose tissue, adipocytes, Not detected); on the kidney slide, assess unstained neighboring cells for background without assuming every cell outside a collecting duct is EMX2-negative.
Positive control tissue: Cerebellum (GLUC cells - cytoplasm/membrane, HPA Medium)
Negative control tissue: Adipose tissue (HPA Not detected)
ICC-IF cell lines (HPA subcellular resource): HPA ICC-IF images show EMX2 in EFO-21, RT-4, Rh30, with annotated localisation: Nucleoplasm (approved) (HPA subcellular).
Technical controls: Include a no-primary, secondary-only control; use host- and isotype-matched immunoglobulin for a monoclonal primary or host-matched normal immunoglobulin for a polyclonal primary, plus an EMX2-knockout biological negative if available (standard IHC control practice). For chromogenic kidney sections, block endogenous peroxidase and check for background from blood or tubular pigment; block endogenous biotin if using avidin–biotin detection (standard IHC practice).
⚠️Feasibility: Kidney is a practical paraffin-section starting point because HPA reports Medium collecting-duct staining (HPA: Kidney, collecting ducts, Medium). A target-specific fixation window or fixation effect and an antigen-retrieval dependency are unreported in the supplied evidence; the selected A04322 prostate tissue-IHC caption gives 5 μg/mL but does not report a fixative (selected tissue-IHC caption). HPA shows nucleoplasmic ICC-IF staining in EFO-21, RT-4 and Rh30, but the supplied evidence does not establish that frozen sections or IF are easier than paraffin IHC; kidney pigment and blood can complicate chromogenic interpretation (HPA: EMX2 subcellular; standard IHC practice).
HPA tissue IHC evidence for EMX2
Comprehensive Human Protein Atlas IHC scoring per tissue (reliability: Enhanced — 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 |
|---|---|---|---|---|
| Cerebellum | GLUC cells - cytoplasm/membrane | Medium | Protein (IHC) | HPA → |
| Endometrium | Cells in endometrial stroma | Low | Protein (IHC) | HPA → |
| Epididymis | Glandular cells | Medium | Protein (IHC) | HPA → |
| Fallopian tube | Non-ciliated cells | Medium | Protein (IHC) | HPA → |
| Kidney | Collecting ducts | Medium | Protein (IHC) | HPA → |
Undetected expression · recommended 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 → |
| Breast | Adipocytes | Not detected | Protein (IHC) | HPA → |
Section 3
Advanced EMX2 IHC Tips
Troubleshoot EMX2 staining in paraffin sections by checking retrieval, nuclear localisation, cell identity and controls before comparing staining across samples.
How should I retrieve EMX2 antigen in paraffin sections with weak nuclear staining?
Use Tris-EDTA at pH 9.0 for heat-induced retrieval at 95–98 °C for 20 minutes (page retrieval rule: nuclear antigen). Let sections cool in the retrieval solution, then use the same wash, antibody incubation and detection conditions across the comparison set (standard IHC practice). If staining remains weak, test a shorter and a longer heating interval on matched sections while monitoring tissue integrity (standard IHC practice). Score nuclear signal separately from diffuse cytoplasmic color, because EMX2 is nuclear and HPA reports mainly nuclear tissue expression (UniProt Q04743 localisation; HPA tissue IHC profile).
Could fixation explain weak EMX2 staining in my paraffin sections?
The supplied EMX2 tissue-IHC caption reports human prostate staining at 5 μg/mL but does not state the fixative (A04322 tissue-IHC caption). Target-specific sensitivity to fixative type or fixation time is therefore unknown from the supplied evidence (A04322 tissue-IHC caption). Record the fixative and processing history for each block, and compare similarly processed sections under identical retrieval and detection conditions (standard IHC practice). If an internal control loses nuclear staining across the section, assess tissue preservation and reagent performance before assigning the loss to EMX2 biology (standard IHC practice; UniProt Q04743 localisation).
How should I troubleshoot cytoplasmic EMX2 staining when I expect nuclei?
Treat nucleoplasmic staining as the primary pattern to assess: HPA approves nucleoplasm as EMX2’s main subcellular location and reports mainly nuclear tissue expression (HPA subcellular; HPA tissue IHC profile). UniProt also records EMX2 in axons within the olfactory mucosa and olfactory bulb glomeruli, so localisation can depend on anatomical context (UniProt Q04743 localisation). In routine chromogenic sections, compare cytoplasmic color with matched negative controls and inspect whether nuclei retain distinct signal (standard IHC practice). If color follows damaged tissue, section edges or multiple unrelated cell types, repeat blocking and detection checks before interpreting it as EMX2 (standard IHC practice).
Could an EMX2 isoform or hidden epitope explain inconsistent staining?
EMX2 has 2 annotated isoforms, but the supplied record does not identify the catalog antibody’s epitope or establish which isoforms it detects (UniProt Q04743 isoforms; supplied antibody evidence). Ask whether the immunogen sequence is shared between isoforms before interpreting a missing cell population as isoform-specific loss (standard antibody validation practice). The annotated protein has no transmembrane segment, signal peptide, glycosylation site or modified residue in this record, so those annotations do not identify an epitope-side retrieval requirement (UniProt Q04743 topology, processing and PTMs). Compare retrieval conditions on matched sections and require compartment-consistent controls before attributing differences to isoforms (standard IHC practice; HPA subcellular).
How can I check EMX2 localisation by IF alongside chromogenic IHC?
For multiplex IF, pair EMX2 with a validated marker for the expected cell population, such as collecting duct cells when examining kidney, and assess overlap at the single-cell level (HPA tissue IHC: kidney collecting ducts; standard IF practice). Choose a fluorophore in a channel with low measured tissue autofluorescence, and include single-stain controls to assess bleed-through (standard IF practice). EMX2’s expected nucleoplasmic location calls for permeabilisation that permits antibody access to nuclei; optimise it for the specimen and antibody (HPA subcellular; standard IF practice). Keep IF conclusions separate from the chromogenic IHC result because the readouts and background sources differ (standard IHC/IF practice).
What should I check when EMX2 chromogenic staining is widespread?
Inspect a section processed without primary antibody to identify signal from the detection system, and include a known expressing section to check whether the assay worked (standard IHC practice). Block endogenous peroxidase before a peroxidase and DAB workflow, and check whether pigment or precipitate resembles the reaction product (standard IHC practice). Shorten chromogen development or titrate the primary antibody if color obscures nuclei; the reported 5 μg/mL belongs specifically to the A04322 prostate image (standard IHC practice; A04322 tissue-IHC caption). EMX2 is reported mainly in nuclei, so diffuse color across unrelated compartments needs control-supported interpretation (HPA tissue IHC profile).
How should I quantify EMX2 staining across paraffin sections? ⚠ ANSWER MARKED FOR VERIFICATION
Define the anatomical region and cell population before scoring, then record the percentage of positive nuclei and their intensity to calculate a nuclear H-score (standard IHC quantification practice; HPA tissue IHC profile). Alternatively, report positive nuclei per mm² when cell density varies across fields (standard IHC quantification practice). Normalise counts to the number of evaluable cells or sampled tissue area, and apply the same threshold, magnification and exclusion rules to every section (standard IHC quantification practice). Keep cytoplasmic staining in a separate category, since nucleoplasm is the approved main location and tissue expression is mainly nuclear (HPA subcellular; HPA tissue IHC profile).
How do I distinguish true EMX2 staining from section artefacts?
Give greatest weight to reproducible nuclear staining in an anatomically identified cell population, consistent with EMX2’s approved nucleoplasmic location and mainly nuclear tissue pattern (HPA subcellular; HPA tissue IHC profile). Cell identity matters: HPA reports medium staining in kidney collecting ducts but no detection in adipocytes from adipose tissue (HPA tissue IHC: kidney; HPA tissue IHC: adipose tissue). Review section edges and necrotic regions separately, since local damage can create misleading color (standard IHC practice). Use a no-primary control to assess detection background, including endogenous enzyme signal, before interpreting staining in the wrong compartment or cell type as biological EMX2 expression (standard IHC practice).
Boster reagents
Best EMX2 / Homeobox protein EMX2 IHC Antibodies
Three anti-EMX2 antibodies have human tissue IHC images; one also has a human tissue IF image (catalog image captions). Human and mouse reactivity is listed for A04322-2 (catalog reactivity).
Real IHC data
Anti-Homeobox protein EMX2 EMX2 Antibody
Cat # A04322
Real IHC data
Anti-Homeobox protein EMX2 EMX2 Antibody
Cat # A04322-1
Real IHC data
Anti-Homeobox protein EMX2 Emx2 Antibody
Cat # A04322-2
A04322 has a human prostate IHC image, and A04322-1 has human lung IHC and IF images (catalog image captions). A04322-2 has a paraffin-embedded human brain IHC image and lists Human and Mouse reactivity; its image does not establish mouse IHC performance (catalog image caption; catalog reactivity).
Which to pick: For paraffin-section IHC, choose A04322-2: its human brain caption explicitly specifies paraffin embedding and 1:100 dilution; the fixative is unreported (A04322-2 IHC image caption). For human tissue IF, choose A04322-1 at a starting concentration of 20 μg/mL; its IF image shows human lung tissue, while ICC validation is unreported (A04322-1 catalog applications; IF image caption; catalog dilution). For a mouse sample, A04322-2 is the only listed mouse-reactive option, although its IHC image is human (catalog reactivity; A04322-2 IHC image caption).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry Q04743 (EMX2_HUMAN, Homeobox protein EMX2).
- Human Protein Atlas. EMX2 tissue IHC expression (reliability: Enhanced).
- Human Protein Atlas. EMX2 subcellular location (ICC-IF): Localized to the nucleoplasm..
- Human Protein Atlas. EMX2 antibody validation summary (2 antibodies).
- EMX2 gene expression predicts liver metastasis and survival in colorectal cancer. BMC cancer 2017 — PMC5568393.
- Downregulation of EMX2 is associated with clinical outcomes in lung adenocarcinoma patients. Clinical lung cancer 2011 — PMC3285542.
- Asymmetric mechanotransduction by hair cells of the zebrafish lateral line. Current biology : CB 2023 — PMC12427178.
- Emx2 underlies the development and evolution of marsupial gliding membranes. Nature 2024 — PMC11062917.
- PubMed PMID:11549315 — UniProt-cited evidence.
- PubMed PMID:11230166 — UniProt-cited evidence.
- PubMed PMID:14702039 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for EMX2 (Homeobox protein EMX2). Expected localisation Mainly nuclear in tissues (HPA tissue IHC); also axonal (UniProt). Antigen retrieval: Tris-EDTA pH 9.0 HIER, 95–98 °C, 20 min (rule: nuclear antigen). Validated IHC antibody: A04322 at 5 μg/mL (the product's own IHC validation image is shown). Controls (HPA): positive Cerebellum (GLUC cells - cytoplasm/membrane); negative Adipose tissue. IHC workflow; specimen preparation unspecified. Protocol steps: 1. Sample: Tissue sections; selected-image fixative not specified (standard IHC workflow); 2. Fixation: Image fixative and duration unreported (datasheet A04322); 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-induced epitope retrieval in Tris-EDTA buffer, pH 9.0 , 20 min at 95–98 °C…; 6. Peroxidase block: 3% H2O2, 10 min , room temperature (standard); 7. Blocking: 10% normal serum of the secondary host, 30 min , room temperature (standard); 8. Primary antibody: Rabbit anti-EMX2, 5 μg/mL (datasheet A04322); 9. Primary incubation: Overnight at 4 °C (standard). Watch for: Fixation: Keep fixation consistent across paraffin sections. (standard IHC practice; not target-specific); Caveat: Cerebellar GLUC cells show cytoplasm/membrane staining (HPA tissue IHC); Isoform / epitope: 2 isoforms; shared epitope status is unknown (UniProt); Regulation: Expression varies by tissue (HPA tissue IHC). Evidence: UniProt Q04743, HPA tissue IHC · Enhanced, HPA ICC-IF · nucleoplasm., Datasheet A04322, PMC5568393, PMC3285542. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/EMX2/immunohistochemistry-ihc-guide.