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CAPN2 / Calpain-2 catalytic subunit · IHC design guide
Design Immunohistochemistry for CAPN2
Plan CAPN2 chromogenic IHC in paraffin sections with the IHC-validated antibody at 0.5–1 μg/mL (datasheet: A03492). Use high-staining bronchial respiratory epithelium as a reference and assess cytoplasmic staining by cell type (HPA tissue IHC).
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
CAPN2 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 | Cytoplasm observed in tissue; membrane translocation is a molecular expectation (HPA tissue IHC; UniProt) | |
| Staining pattern | Cytoplasmic staining in several cell types, including endothelium (HPA tissue IHC) | |
| Antigen retrieval | Citrate pH 6 HIER, heat-mediated (datasheet A03492) | |
| Positive control | Bronchus+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 paraffin-section fixation consistent (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 A03492) | |
| Caveat | Staining varies by cell type; score each population separately (HPA tissue IHC) | |
| Regulation | Expression regulation is not specified (UniProt) | |
| Isoform / epitope | 2 isoforms; residues 2–19 are removed, but the antibody epitope is unknown (UniProt) |
Section 1
Recommended CAPN2 IHC & IF Protocols
The catalog antibody protocol specifies citrate pH 6 retrieval (datasheet A03492). Two published CAPN2 IHC protocols provide tissue examples (PMC5716693; PMC10022304).
| Sample | Paraffin-embedded human intestinal cancer tissue; fixative not specified (datasheet A03492) |
| Fixation | Image fixative and duration unreported (datasheet A03492); verify before use. |
| Sectioning | 4–5 µm sections on charged slides (standard) |
| Deparaffinisation | Xylene, graded ethanol series to water (standard) |
| Antigen retrieval | Heat retrieval: Citrate pH 6, 20 min (datasheet A03492) |
| Peroxidase block | 3% H2O2, 10 min, room temperature (standard) |
| Blocking | 10% goat serum (datasheet A03492) |
| Primary antibody | Rabbit anti-CAPN2, 0.5-1μg/ml (datasheet A03492) |
| Primary incubation | Overnight at 4 °C (datasheet A03492) |
| Detection | Streptavidin-biotin complex (SABC), DAB chromogen (datasheet A03492) |
| Counterstain | Hematoxylin, blue, dehydrate and mount (standard) |
| Expected result | CAPN2-positive staining in respiratory epithelial cells of bronchus (HPA tissue IHC: High). HPA tissue profile: Cytoplasmic expression in several different cell types, including endothelial cells. No signal in the no-primary control. |
💡Decision noteStart with citrate pH 6 heat retrieval: the catalog datasheet specifies it (datasheet A03492), and both published protocols use it (PMC5716693; PMC10022304).
Section 2
What Is the Expected CAPN2 Staining Pattern?
CAPN2 should appear mainly in the cytoplasm of several cell types, including endothelial cells (HPA tissue IHC). Bronchial respiratory epithelial cells show high staining; several glandular cell populations show medium staining (HPA tissue IHC). CAPN2 is cytoplasmic and can move to the plasma membrane upon calcium binding; it has no transmembrane segment (UniProt P17655). HPA rates the tissue staining profile Approved, with medium consistency between staining and RNA expression (HPA tissue IHC).
| Distinct cytoplasmic staining in bronchial respiratory epithelial cells, with lighter staining in nearby cells. | A strong epithelial signal fits the reported High level in bronchus (HPA tissue IHC). Judge cell identity and cytoplasmic location together: CAPN2 is broadly expressed, so staining in additional cells is possible (UniProt P17655 tissue specificity; HPA tissue IHC). |
| Predominantly sharp nuclear staining, or a uniform rim around every cell with little cytoplasmic signal. | This is discordant with the mainly cytoplasmic tissue pattern (HPA tissue IHC). CAPN2 can move to the plasma membrane after calcium binding, but it has no transmembrane segment (UniProt P17655). Check the control slide and detection conditions before interpreting a rim as CAPN2. |
| Strong staining confined to adipocytes or to esophageal squamous epithelial cells. | Both cell populations are reported as Not detected (HPA tissue IHC). Treat isolated strong staining there as suspect; cross-reactivity or endogenous detection activity are possibilities (general IHC practice). A negative HPA observation does not prove that every specimen must be unstained. |
| A diffuse haze covers cells and spaces between them, obscuring cell boundaries. | An uninterpretable field cannot establish CAPN2 localization (general IHC practice). Compare it with a no-primary control for nonspecific detection or endogenous activity, then optimize blocking, washing, and detection conditions (general IHC practice). |
| No staining in bronchial respiratory epithelial cells on the test section. | That conflicts with the reported High staining in bronchus (HPA tissue IHC). First check a positive-control section and run controls for the IHC procedure (general IHC practice). HPA's Approved rating has medium staining–RNA consistency, so one negative section alone cannot settle target absence (HPA tissue IHC). |
💡Expected CAPN2 appearanceCall a result positive when identifiable bronchial respiratory epithelial cells show distinct, predominantly cytoplasmic high staining (HPA tissue IHC); a field-wide haze or strong staining limited to reported undetected cell populations is suspect (HPA tissue IHC; general IHC practice).
| Cell and tissue context | Reported levels range from High in bronchial respiratory epithelium to Medium in several glandular cell populations, and Not detected in adipocytes (HPA tissue IHC). Score the named cell population, not the whole section. |
| Localization and calcium response | CAPN2 is cytoplasmic and can translocate to the plasma membrane upon calcium binding (UniProt P17655). A membrane-associated component can therefore be plausible, but a uniformly membrane-only IHC pattern needs control review (UniProt P17655; general IHC practice). |
| Antibody validation | HPA024470 is rated Approved for IHC, and the tissue profile has medium agreement between staining and RNA expression (HPA antibody validation; HPA tissue IHC). These ratings support comparison with the reported pattern but do not verify every stained cell in a new specimen. |
| Processing and isoforms | UniProt reports 2 isoforms and a propeptide at residues 2–19, with the mature chain spanning residues 20–700 (UniProt P17655). Antibody epitope location is not supplied, so these features cannot predict an isoform-specific or processing-specific IHC pattern. |
| IF/ICC: where should signal appear? | Mainly in the cytosol; HPA also reports connecting-piece and mid-piece staining and additional principal-piece staining in sperm (HPA subcellular ICC-IF). Those ICC-IF locations are context-specific and should not be substituted for the tissue IHC pattern. |
| Situation | Likely cause | Next action |
|---|---|---|
| Bronchial respiratory epithelium is blank. | This differs from the reported High signal (HPA tissue IHC); an IHC procedure problem or specimen variation may be involved (general IHC practice). | Review a positive-control section, primary-antibody use, detection reagents, and counterstain (general IHC practice). Optimize antigen retrieval as a general IHC step; target-specific fixation or retrieval sensitivity is unreported. |
| Every cell looks uniformly positive. | A uniform pattern does not reflect the reported differences among cell populations (HPA tissue IHC). Nonspecific detection or endogenous activity may contribute (general IHC practice). | Compare with a no-primary control, then check blocking, washing, and the detection system (general IHC practice). Reassess staining in identifiable cells. |
| The signal is mainly nuclear. | A nuclear-dominant pattern conflicts with the reported cytoplasmic localization (HPA tissue IHC; UniProt P17655). | Check focus and counterstain interpretation, compare the control slide, and confirm the pattern with an independently validated antibody if available (general IHC practice). |
| Adipocytes show strong, discrete staining. | Adipocytes are reported as Not detected in adipose tissue and breast (HPA tissue IHC); cross-reactivity or detection background is possible (general IHC practice). | Compare the same cell population in a no-primary control and inspect adjacent positive cell populations before assigning CAPN2 positivity (general IHC practice). |
| Only a narrow cell-edge signal is visible. | CAPN2 can translocate to the plasma membrane upon calcium binding (UniProt P17655), but tissue IHC is described chiefly as cytoplasmic (HPA tissue IHC). | Check whether cytoplasmic signal is also present and whether the edge signal persists above the no-primary control (general IHC practice). Avoid calling a membrane-only pattern definitive. |
| Weak staining in lung alveolar cells is scored as a failed run. | Alveolar cells are listed at Low staining, while bronchial respiratory epithelial cells are High (HPA tissue IHC). | Score the specific cell population and compare with an appropriate positive-control section (general IHC practice). Do not apply the bronchial intensity expectation to alveolar cells. |
Experiment evidence
IHC & IF images showing CAPN2 staining
A03492 · IHCIHC analysis of Calpain 2 using anti-Calpain 2 antibody (A03492). Calpain 2 was detected in paraffin-embedded section of human intestinal ca
A03492 · IHCIHC analysis of Calpain 2 using anti-Calpain 2 antibody (A03492). Calpain 2 was detected in paraffin-embedded section of human lung cancer t
A03492 · IFIF analysis of Calpain 2 using anti-Calpain 2 antibody (A03492). Calpain 2 was detected in immunocytochemical section of HELA cells. Enzyme
M03492 · IHCIHC analysis of Calpain 2 using anti-Calpain 2 antibody (M03492). Calpain 2 was detected in paraffin-embedded section of human intestinal ca
M03492 · IHCIHC analysis of Calpain 2 using anti-Calpain 2 antibody (M03492). Calpain 2 was detected in paraffin-embedded section of human mammary cance
M03492 · IFIF analysis of Calpain 2 using anti-Calpain 2 antibody (M03492). Calpain 2 was detected in immunocytochemical section of A549 cells. Enzyme
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000162909-CAPN2/tissue/cerebral+cortex#imid_6307416
HPA · BronchusHuman Protein Atlas IHC, Bronchus. Source: https://www.proteinatlas.org/ENSG00000162909-CAPN2/tissue/bronchus#imid_6307397
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000162909-CAPN2/tissue/colon#imid_6307342
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000162909-CAPN2/tissue/liver#imid_6307351
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA024470; green = CAPN2, blue = nucleus, red = microtubules.
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA024470; green = CAPN2, blue = nucleus, red = microtubules.
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for CAPN2 IHC & IF
🧪Run bronchus first and expect respiratory epithelial cells to stain (HPA: bronchus, respiratory epithelial cells, High). Use adipose tissue as a negative comparator, focusing on adipocytes (HPA: adipose tissue, adipocytes, Not detected); on the bronchus slide, use neighboring cells as internal background references only if they are empirically unstained, because the supplied HPA row identifies no negative cell type there (HPA: bronchus row).
Positive control tissue: Bronchus (Respiratory epithelial cells, HPA High)
Negative control tissue: Adipose tissue (HPA Not detected)
ICC-IF cell lines (HPA subcellular resource): HPA ICC-IF images show CAPN2 in A-431, U-251MG, U2OS, Sperm, with annotated localisation: Cytosol (supported), Connecting piece (approved), Mid piece (approved) (HPA subcellular).
Technical controls: Include a no-primary, secondary-only control; host- and clonality-matched rabbit IgG isotype control; and, if available, a CAPN2-knockout biological negative (caption: rabbit primary antibody; standard IHC controls). Block endogenous peroxidase and check for endogenous biotin background when using the caption’s biotin-based, DAB detection on bronchus (caption: SABC with DAB; standard chromogenic IHC practice).
⚠️Feasibility: A target-specific fixation window or fixation effect is unreported, and the fixative for the selected A03492 paraffin-section image is unreported (caption: fixative not stated). The demonstrated IHC approach uses citrate retrieval at pH 6 for 20 minutes; the supplied evidence does not establish that frozen sections or IF are easier (caption: citrate retrieval; HPA: ICC-IF images). Assess bronchial background with the peroxidase and biotin controls because the demonstrated detection uses a biotin-based DAB system (caption: SABC with DAB; standard chromogenic IHC practice).
HPA tissue IHC evidence for CAPN2
Comprehensive Human Protein Atlas IHC scoring per tissue (reliability: Approved — 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 |
|---|---|---|---|---|
| Bronchus | Respiratory epithelial cells | High | Protein (IHC) | HPA → |
| Adrenal gland | Glandular cells | Medium | Protein (IHC) | HPA → |
| Appendix | Glandular cells | Medium | Protein (IHC) | HPA → |
| Cerebellum | Bergmann glia - cytoplasm/membrane | Medium | Protein (IHC) | HPA → |
| Fallopian tube | Glandular cells | Medium | Protein (IHC) | HPA → |
Undetected expression · recommended negative controls
| Tissue | Cell type | Level | Evidence | Source |
|---|---|---|---|---|
| Adipose tissue | Adipocytes | Not detected | Protein (IHC) | HPA → |
| Breast | Adipocytes | Not detected | Protein (IHC) | HPA → |
| Caudate | Glial cells | Not detected | Protein (IHC) | HPA → |
| Colon | Endothelial cells | Not detected | Protein (IHC) | HPA → |
| Duodenum | Glandular cells | Not detected | Protein (IHC) | HPA → |
Section 3
Advanced CAPN2 IHC Tips
Troubleshoot CAPN2 staining in paraffin sections by checking retrieval, cell type, subcellular pattern and controls before comparing chromogenic signal (HPA tissue IHC; UniProt P17655).
What should I change when CAPN2 staining is weak after antigen retrieval?
Start with heat-mediated citrate buffer at pH 6 for 20 minutes on paraffin sections (datasheet A03492). The selected tissue image used that retrieval before overnight incubation at 4°C with 1 μg/ml primary antibody (A03492 tissue-IHC caption). If staining is weak, check heating consistency, section adhesion and whether the retrieval solution maintained its intended pH across the run (standard IHC practice). Compare a positive control and a no-primary control in the same run before increasing retrieval intensity (standard IHC practice). Excessive heating can damage tissue morphology and make a stronger signal harder to interpret (standard IHC practice).
Can fixation explain weak or uneven CAPN2 staining?
Target-specific fixation sensitivity is unknown: the selected paraffin-section caption does not state its fixative (A03492 tissue-IHC caption). For new specimens, document the fixative, fixation duration and processing conditions, and keep them consistent across samples being compared (standard IHC practice). Underfixation can impair morphology, while prolonged fixation can reduce epitope accessibility in chromogenic IHC generally; neither effect has been established specifically for CAPN2 here (standard IHC practice; A03492 tissue-IHC caption). If staining varies between blocks, repeat citrate retrieval at pH 6 for 20 minutes with a control section from each block (datasheet A03492; standard IHC practice). Interpret remaining differences alongside preserved morphology rather than assigning them to CAPN2 biology (standard IHC practice).
Should CAPN2 stain the cytoplasm, plasma membrane or both?
Expect predominantly cytoplasmic signal in tissue sections: HPA describes cytoplasmic expression in several cell types, including endothelial cells (HPA tissue IHC). CAPN2 is listed in the cytoplasm and at the cell membrane, with plasma-membrane translocation upon Ca(2+) binding (UniProt P17655). It has no transmembrane segment, so a membrane-adjacent rim should be interpreted in cellular context rather than as proof of an integral membrane protein (UniProt P17655; standard IHC interpretation). Compare the suspected rim with cytoplasmic staining in neighboring cells and with the no-primary control on the same section (standard IHC practice). Record compartment and cell type separately when scoring (standard IHC practice).
Could isoforms or processing change which CAPN2 structures the antibody detects?
CAPN2 has 2 annotated isoforms, and the supplied record does not map the catalog antibody's epitope to either one (UniProt P17655; A03492 tissue-IHC caption). The record lists a propeptide at residues 2–19 and a catalytic-subunit chain at 20–700, so epitope position matters when interpreting staining after processing (UniProt P17655). Check the antibody's immunogen or epitope documentation before claiming isoform-specific or processed-chain detection (standard IHC interpretation). CAPN2 has 0 annotated glycosylation sites and an N-acetylalanine at residue 2; neither observation establishes antibody recognition of a modified epitope (UniProt P17655). Use an independent epitope or orthogonal assay for unresolved specificity questions (standard IHC practice).
How should I investigate CAPN2 localisation by multiplex IF?
Treat IF as a separate application from this chromogenic IHC protocol; the selected antibody evidence here is a paraffin-section IHC caption (A03492 tissue-IHC caption). In a pilot multiplex panel, pair CAPN2 with a marker for the expected cell type, such as respiratory epithelial cells in bronchus, and compare compartment patterns within identified cells (HPA tissue IHC; standard IF practice). Select a far-red fluorophore when tissue autofluorescence obscures shorter wavelengths, and include single-stain and no-primary controls (standard IF practice). For a cytosolic epitope, optimise mild permeabilisation; CAPN2 has no transmembrane segment, but the catalog antibody's epitope side is unspecified (UniProt P17655; standard IF practice). HPA reports a supported cytosolic IF localisation that can guide, rather than validate, this comparison (HPA subcellular).
How can I reduce diffuse brown staining without losing CAPN2 signal?
First inspect no-primary and secondary-only controls to locate nonspecific chromogenic signal before changing the CAPN2 antibody concentration (standard IHC practice). The selected image used 10% goat serum blocking, 1 μg/ml primary antibody overnight at 4°C, and a biotin-based DAB detection sequence (A03492 tissue-IHC caption). If background persists, optimise blocking and washing, and assess endogenous peroxidase and biotin contributions for the chosen detection system (standard IHC practice). Titrate the primary around the documented starting condition while keeping retrieval and exposure to chromogen consistent between sections (A03492 tissue-IHC caption; standard IHC practice). Judge improvements by cellular contrast and preserved morphology, not brown intensity alone (standard IHC practice).
What is a defensible way to quantify CAPN2 IHC across samples? ⚠ ANSWER MARKED FOR VERIFICATION
Define the cell population and compartment before scoring, because CAPN2 can appear in cytoplasm and at the cell membrane (UniProt P17655; standard IHC practice). For chromogenic sections, report the percentage of positive target cells and an intensity-weighted H-score, using the same intensity categories and thresholds across the series (standard IHC practice). Alternatively, report positive-cell density per mm² of viable, annotated tissue when cell counts are the study endpoint (standard IHC practice). Normalise to the number of eligible cells or viable tissue area, and exclude folds, necrosis and section edges by a prespecified rule (standard IHC practice). Keep staining and imaging conditions consistent, with controls in each run (standard IHC practice).
How do I distinguish plausible CAPN2 staining from artefact?
A plausible result has cellular cytoplasmic staining, sometimes membrane-adjacent, in a morphologically identifiable cell population (HPA tissue IHC; UniProt P17655). HPA reports high staining in bronchial respiratory epithelial cells but no detection in adipocytes in adipose tissue; these are contextual references, not universal acceptance criteria (HPA tissue IHC). Treat isolated nuclear-only signal, necrotic debris, section-edge accentuation or staining confined to damaged tissue as suspect until controls and morphology support it (UniProt P17655; standard IHC interpretation). Check no-primary controls and endogenous peroxidase contributions before assigning diffuse DAB signal to CAPN2 (standard IHC practice). HPA labels its tissue IHC reliability Approved with medium staining–RNA consistency, so interpret unexpected patterns cautiously (HPA tissue IHC).
Boster reagents
Best CAPN2 / Calpain-2 catalytic subunit IHC Antibodies
Anti-CAPN2 antibodies have IHC images from paraffin-embedded human cancer tissue, rat small intestine, and mouse lung, plus IF/ICC images from HELA, A549, and U251 cells (catalog image captions).
Real IHC data
Anti-Calpain 2/CAPN2 Antibody ®
Cat # A03492
Real IHC data
Anti-Calpain 2 CAPN2 Antibody ® (monoclonal, 8I6)
Cat # M03492
A03492 will render with IHC data from paraffin-embedded human intestinal and lung cancer tissue and rat small intestine, and IF/ICC data from HELA cells (A03492 image captions). M03492 will render with IHC data from paraffin-embedded human intestinal and mammary cancer tissue and mouse lung, and IF/ICC data from A549 and U251 cells (M03492 image captions).
Which to pick: For paraffin-section IHC, choose A03492 for the rabbit antibody’s citrate pH 6 example or M03492 for the mouse monoclonal 8I6 antibody’s EDTA pH 8.0 example; fixation is unreported in both captions (A03492 and M03492 IHC image captions; M03492 catalog clone). For IF/ICC, both list that application at 2 μg/ml; A03492 has a HELA image, while M03492 has A549 and U251 images (catalog applications and IF dilutions; IF image captions). For cross-species work, A03492 lists human, mouse, and rat reactivity, while M03492 lists human, monkey, and mouse reactivity; the IHC images document rat tissue for A03492 and mouse tissue for M03492 (catalog reactivity; IHC image captions).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry P17655 (CAN2_HUMAN, Calpain-2 catalytic subunit).
- Human Protein Atlas. CAPN2 tissue IHC expression (reliability: Approved).
- Human Protein Atlas. CAPN2 subcellular location (ICC-IF): Mainly localized to the cytosol, connecting piece and mid piece. In addition localized to the principal piece..
- Human Protein Atlas. CAPN2 antibody validation summary (1 antibodies).
- Overexpression of CAPN2 promotes cell metastasis and proliferation via AKT/mTOR signaling in renal cell carcinoma. Oncotarget 2017 — PMC5716693.
- Silencing CAPN2 Expression Inhibited Castration-Resistant Prostate Cancer Cells Proliferation and Invasion via AKT/mTOR Signal Pathway. BioMed research international 2017 — PMC5322456.
- CAPN2 promotes apalutamide resistance in metastatic hormone-sensitive prostate cancer by activating protective autophagy. Journal of translational medicine 2024 — PMC11155045.
- Changes in calpain-2 expression during glioblastoma progression predisposes tumor cells to temozolomide resistance by minimizing DNA damage and p53-dependent apoptosis. Cancer cell international 2023 — PMC10022304.
- PubMed PMID:2852952 — UniProt-cited evidence.
- PubMed PMID:10944468 — UniProt-cited evidence.
- PubMed PMID:14702039 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for CAPN2 (Calpain-2 catalytic subunit). Expected localisation Cytoplasm observed in tissue; membrane translocation is a molecular expectation (HPA tissue IHC; UniProt). Antigen retrieval: Citrate pH 6 HIER, heat-mediated (datasheet A03492). Validated IHC antibody: A03492 at 0.5-1μg/ml (the product's own IHC validation image is shown). Controls (HPA): positive Bronchus (Respiratory epithelial cells); negative Adipose tissue. IHC-P workflow on paraffin sections; fixative unspecified. Protocol steps: 1. Sample: Paraffin-embedded human intestinal cancer tissue; fixative not specified (datasheet A03492); 2. Fixation: Image fixative and duration unreported (datasheet A03492); 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: Citrate pH 6 , 20 min (datasheet A03492); 6. Peroxidase block: 3% H2O2, 10 min , room temperature (standard); 7. Blocking: 10% goat serum (datasheet A03492); 8. Primary antibody: Rabbit anti-CAPN2, 0.5-1μg/ml (datasheet A03492); 9. Primary incubation: Overnight at 4 °C (datasheet A03492). Watch for: Fixation: Keep paraffin-section fixation consistent (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 A03492); Caveat: Staining varies by cell type; score each population separately (HPA tissue IHC); Isoform / epitope: 2 isoforms; residues 2–19 are removed, but the antibody epitope is unknown (UniProt); Regulation: Expression regulation is not specified (UniProt). Evidence: UniProt P17655, HPA tissue IHC · Approved, HPA ICC-IF · Mainly localized to the cytosol, connecting piece and mid piece. In…, Datasheet A03492, PMC5716693, PMC10022304. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/CAPN2/immunohistochemistry-ihc-guide.