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KCNMA1 / Calcium-activated potassium channel subunit alpha-1 · IHC design guide
Design Immunohistochemistry for KCNMA1
Plan KCNMA1 staining in paraffin sections using the catalog antibody at 0.5–1 µg/mL (datasheet PB9227). Assess cytoplasmic and membranous staining with controls, mindful of low consistency between staining and RNA expression (HPA tissue IHC).
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
KCNMA1 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 | Observed cytoplasmic/membranous (HPA tissue IHC); cell membrane expected (UniProt) | |
| Staining pattern | Duodenal glandular cells: cytoplasmic and membranous staining (HPA tissue IHC) | |
| Antigen retrieval | Citrate pH 6 HIER, heat-mediated (datasheet PB9227) | |
| Positive control | Duodenum+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 sections (standard IHC practice; not target-specific) | |
| Caveat | Low consistency between staining and RNA expression (HPA tissue IHC) | |
| Regulation | Expression regulation unreported (UniProt) | |
| Isoform / epitope | 7 isoforms; extracellular versus cytoplasmic epitope matters (UniProt) |
Section 1
Recommended KCNMA1 IHC & IF Protocols
Compare the catalog antibody’s IHC-P protocol (datasheet: PB9227) with published chromogenic IHC protocols for human colorectal biopsies (PMC6406553) and yak lung (PMC11110679).
| Sample | Paraffin-embedded mouse intestine tissue; fixative not specified (datasheet PB9227) |
| Fixation | Image fixative and duration unreported (datasheet PB9227); 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 PB9227) |
| Peroxidase block | 3% H2O2, 10 min, room temperature (standard) |
| Blocking | 10% goat serum (datasheet PB9227) |
| Primary antibody | Rabbit anti-KCNMA1, 0.5-1μg/ml (datasheet PB9227) |
| Primary incubation | Overnight at 4 °C (datasheet PB9227) |
| Detection | Streptavidin-biotin complex (SABC), DAB chromogen (datasheet PB9227) |
| Counterstain | Hematoxylin, blue, dehydrate and mount (standard) |
| Expected result | KCNMA1-positive staining in glandular cells of duodenum (HPA tissue IHC: High). HPA tissue profile: Cytoplasmic and membranous expression in several tissues. No signal in the no-primary control. |
💡Decision noteStart with heat-mediated citrate pH 6 retrieval for the catalog antibody (datasheet: PB9227). The colorectal study used microwave pretreatment but did not report a retrieval buffer (PMC6406553).
Section 2
What Is the Expected KCNMA1 Staining Pattern?
KCNMA1 is a seven-pass cell-membrane channel (UniProt Q12791 topology). In tissue IHC, expect membranous and cytoplasmic staining, including duodenal glandular cells, fallopian-tube ciliated cells and testicular spermatogonia (HPA tissue IHC). HPA rates its tissue staining “Approved” but reports low agreement with RNA expression and pending external verification (HPA tissue IHC reliability). Interpret the pattern at the cell level, alongside controls.
| Membranous staining with some cytoplasmic signal in duodenal glandular cells (HPA tissue IHC). | This fits the reported tissue pattern and UniProt cell-membrane location (HPA tissue IHC; UniProt Q12791). HPA calls duodenal glandular staining High, but its Approved rating has a low RNA–staining consistency caveat (HPA tissue IHC). |
| Strong staining at cilia tips in fallopian-tube ciliated cells (HPA: High in ciliated cells). | A concentrated apical signal fits the HPA observation; bronchial ciliary rootlets are a separate Medium example (HPA tissue IHC). Score the named cell structure rather than assuming every ciliated cell or every part of a cilium must stain. |
| Predominantly nuclear staining, without a convincing membrane-associated pattern. | This does not fit UniProt's cell-membrane assignment or HPA's membranous and cytoplasmic tissue profile (UniProt Q12791; HPA tissue IHC). Treat it as suspect until controls and antibody specificity are checked; morphology alone cannot identify the source of signal. |
| Strong signal in adipocytes or pancreatic exocrine glandular cells (HPA: Not detected). | These are cell types in which HPA did not detect staining, so a strong result warrants review for cross-reactivity or endogenous chromogenic activity (HPA tissue IHC; standard IHC practice). HPA's limited validation means its negative observations are comparators, not proof that expression is impossible. |
| Haze across tissue, including areas without a discernible cell pattern. | Diffuse signal is difficult to score as KCNMA1 when it lacks the cell and compartment pattern reported by HPA (HPA tissue IHC). Examine a negative detection control and compare background with the expected positive structures before calling a sample positive (standard IHC practice). |
💡Expected KCNMA1 appearanceCall a convincing positive when membrane-associated staining, with possible cytoplasmic signal, is strongest in HPA High examples such as duodenal glandular cells or fallopian-tube cilia tips; isolated nuclear signal or uniform haze is suspect (UniProt Q12791; HPA tissue IHC).
| Compartment and topology | UniProt places KCNMA1 at the cell membrane with 7 transmembrane segments and a long cytoplasmic region spanning residues 389–1236 (UniProt Q12791 topology). HPA also reports cytoplasmic tissue signal; membrane-only scoring would miss part of its observed IHC profile (HPA tissue IHC). |
| Choice of tissue and cell type | HPA reports High staining in duodenal glandular cells, fallopian-tube cilia tips and spermatogonia; adrenal glandular and cerebellar Purkinje cells are Medium (HPA tissue IHC). Compare the annotated cell type, since neighboring cells need not share its staining level. |
| Breadth and limits of tissue evidence | UniProt describes expression as widespread except in myocytes, while HPA calls tissue RNA specificity low and lists some cell types as not detected by IHC (UniProt Q12791; HPA tissue IHC). These statements support cautious cell-level interpretation, especially because HPA reports low agreement between staining and RNA data. |
| Antibody and IF evidence | HPA lists antibody HPA054648 as IHC Approved, with no ICC validation status; its subcellular page says “Membrane” but lists no ICC-IF image cell lines (HPA antibodies; HPA subcellular). Thus the supplied HPA record supports an IHC pattern more directly than an IF/ICC appearance. |
| Isoforms and target-specific preparation effects | UniProt lists 7 isoforms, but the supplied records do not map an antibody epitope to them or establish isoform-specific staining (UniProt Q12791; HPA antibodies). Target-specific fixation sensitivity and an antigen-retrieval effect are unreported in these sources; choose and assess retrieval using the antibody's own IHC guidance. |
| Situation | Likely cause | Next action |
|---|---|---|
| No signal in duodenal glandular cells or fallopian-tube cilia tips (HPA: High). | A failed IHC run or antibody performance issue is possible; a single negative section cannot distinguish those from biological variation (HPA tissue IHC; standard IHC practice). | Check that the known-positive cell type is present, then verify antibody incubation, retrieval and chromogenic detection against the antibody's IHC instructions and run controls (standard IHC practice). |
| Staining appears mainly nuclear. | A nuclear-dominant pattern conflicts with the assigned cell-membrane location and HPA's membranous and cytoplasmic IHC profile (UniProt Q12791; HPA tissue IHC). | Review cell boundaries and the counterstain; compare a known-positive tissue and a negative detection control before interpreting nuclear colour as target signal (standard IHC practice). |
| Strong staining appears in an HPA not-detected cell type. | Cross-reactivity or endogenous chromogenic activity is possible; HPA reports adipocytes and pancreatic exocrine cells as not detected, with external verification pending (HPA tissue IHC; standard IHC practice). | Compare the same cell type in controls, assess endogenous activity with an appropriate detection control, and confirm any unexpected pattern independently before reporting it (standard IHC practice). |
| Signal is diffuse or obscures tissue structure. | Excess background can obscure the membrane and cell-specific pattern needed for interpretation (HPA tissue IHC; standard IHC practice). | Inspect a negative detection control, review blocking and antibody concentration under the antibody's IHC instructions, and score only interpretable cellular staining (standard IHC practice). |
| Ciliary staining is hard to distinguish from adjacent tissue colour. | HPA places the High fallopian-tube signal at cilia tips and the Medium bronchial signal at rootlets; the relevant structure is small (HPA tissue IHC). | Use the counterstain and morphology to locate ciliated cells, then compare the apical signal with adjacent cells and a detection control (HPA tissue IHC; standard IHC practice). |
| Can this IHC result define the expected IF/ICC pattern? | HPA's subcellular summary says “Membrane,” but supplies no ICC-IF image cell lines, and the listed antibody has no ICC validation status (HPA subcellular; HPA antibodies). | Use membrane localisation as an IF/ICC hypothesis (UniProt Q12791; HPA subcellular). Validate IF/ICC independently with suitable controls; the tissue IHC pattern alone does not establish an IF/ICC result. |
Experiment evidence
IHC & IF images showing KCNMA1 staining
PB9227 · IHCIHC analysis of KCNMA1 using anti-KCNMA1 antibody (PB9227). KCNMA1 was detected in paraffin-embedded section of mouse intestine tissue. Heat
PB9227 · IHCIHC analysis of KCNMA1 using anti-KCNMA1 antibody (PB9227). KCNMA1 was detected in paraffin-embedded section of rat intestine tissue. Heat m
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000156113-KCNMA1/tissue/cerebral+cortex#imid_16132263
HPA · CerebellumHuman Protein Atlas IHC, Cerebellum. Source: https://www.proteinatlas.org/ENSG00000156113-KCNMA1/tissue/cerebellum#imid_16132274
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000156113-KCNMA1/tissue/colon#imid_16126301
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000156113-KCNMA1/tissue/liver#imid_16126294
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for KCNMA1 IHC & IF
🧪Run duodenum first and expect staining in glandular cells (HPA: High in duodenal glandular cells). Use esophageal squamous epithelial cells as the negative tissue (HPA: Not detected in esophageal squamous epithelial cells); on the duodenum slide, treat unstained neighboring non-glandular cells as a background reference, without assuming they are KCNMA1-negative (HPA: High designation applies to glandular cells).
Positive control tissue: Duodenum (Glandular cells, HPA High)
Negative control tissue: Adipose tissue (HPA Not detected)
ICC-IF cell lines (HPA subcellular resource): HPA carries no ICC-IF cell line for KCNMA1; derive a cell-line control from the positive tissue's cell type (Glandular cells) and confirm it by RNA or western blot first.
Technical controls: Include a no-primary, secondary-only control; a concentration- and clonality-matched rabbit IgG isotype control (PB9227 caption: rabbit primary antibody); and knockout tissue or immunogen-peptide blocking where available (standard IHC practice). Quench endogenous peroxidase and check for endogenous biotin background in duodenum (PB9227 caption: biotinylated secondary, streptavidin–biotin complex and DAB detection).
⚠️Feasibility: A target-specific fixation window or fixation effect is unreported, and the selected PB9227 paraffin-section caption does not state the fixative (PB9227 caption: fixative not stated). The reported IHC retrieval is citrate buffer at pH 6 for 20 minutes; retrieval dependence beyond that example is unreported (PB9227 caption: heat-mediated retrieval). Frozen-section and IF ease cannot be established from the supplied evidence; duodenal glandular staining should be checked against background from the biotin-based DAB method (PB9227 caption: SABC/DAB; HPA: High in duodenal glandular cells).
HPA tissue IHC evidence for KCNMA1
Comprehensive Human Protein Atlas IHC scoring per tissue (reliability: Approved — Low consistency between antibody staining and RNA expression data. Pending external verification.). 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 |
|---|---|---|---|---|
| Duodenum | Glandular cells | High | Protein (IHC) | HPA → |
| Fallopian tube | Ciliated cells (tip of cilia) | High | Protein (IHC) | HPA → |
| Testis | Spermatogonia cells | High | Protein (IHC) | HPA → |
| Adrenal gland | Glandular cells | Medium | Protein (IHC) | HPA → |
| Appendix | 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 → |
| Caudate | Glial cells | Not detected | Protein (IHC) | HPA → |
| Esophagus | Squamous epithelial cells | Not detected | Protein (IHC) | HPA → |
| Heart muscle | Cardiomyocytes | Not detected | Protein (IHC) | HPA → |
| Hippocampus | Glial cells | Not detected | Protein (IHC) | HPA → |
Section 3
Advanced KCNMA1 IHC Tips
Troubleshoot KCNMA1 staining in paraffin sections by checking retrieval, cellular pattern, controls, and scoring before interpreting chromogenic signal.
What retrieval conditions should I try when KCNMA1 staining is weak?
Start with heat-mediated citrate antigen retrieval at pH 6 for 20 minutes on paraffin sections (datasheet PB9227; PB9227 image caption). The PB9227 mouse intestine image used this retrieval with 1 µg/ml primary antibody overnight at 4°C, providing a tested starting combination (PB9227 image caption). If staining remains weak, compare a modestly longer heating time on adjacent sections while holding antibody concentration and detection constant (standard IHC practice). Check that sections remain attached and tissue morphology is preserved, since excessive heating can make an apparent signal gain difficult to interpret (standard IHC practice). Score the same cell compartment across conditions rather than choosing the section with the darkest overall DAB staining (standard IHC practice; UniProt Q12791: cell membrane).
How should I troubleshoot suspected fixation effects on KCNMA1 staining?
Target-specific fixation sensitivity is unknown: the PB9227 paraffin-section caption does not state a fixative, and no KCNMA1 fixation comparison is supplied (PB9227 image caption). Record the actual fixative, fixation interval, tissue thickness, and processing history for each specimen before comparing staining (standard IHC practice). Test sections processed under different known conditions side by side using citrate retrieval at pH 6 and the same detection settings (datasheet PB9227; standard IHC practice). Interpret reduced staining alongside morphology and an independently established positive control, because processing differences can alter staining without establishing a KCNMA1-specific mechanism (standard IHC practice). Avoid assigning a fixation effect from topology, phosphorylation sites, or HPA tissue patterns alone (UniProt Q12791 topology and modified residues; HPA tissue IHC).
Where should convincing KCNMA1 DAB signal appear within cells?
Expect a membrane-associated component because KCNMA1 is annotated at the cell membrane, while HPA describes cytoplasmic and membranous staining across several tissues (UniProt Q12791: cell membrane; HPA tissue IHC profile). Review the relevant cell population at high magnification and distinguish a cell boundary pattern from diffuse cytoplasmic DAB deposit (standard IHC practice). For context, HPA reports high staining in duodenal glandular cells and at the tips of fallopian-tube cilia (HPA tissue IHC). A purely nuclear pattern lacks support from the supplied localisation evidence and warrants a control review (UniProt Q12791: cell membrane; HPA subcellular: membrane). Compare adjacent sections under identical retrieval and development conditions before attributing pattern differences to biology (standard IHC practice).
Could epitope position or isoform choice explain discordant KCNMA1 staining?
KCNMA1 has 7 annotated isoforms and 7 transmembrane segments, so epitope position matters when comparing antibodies (UniProt Q12791 isoforms and topology). Its long cytoplasmic region spans residues 389–1236, while several shorter loops face the extracellular side (UniProt Q12791 topology). Obtain the catalog antibody’s immunogen sequence or mapped epitope and check which annotated isoforms retain it before interpreting a negative section (standard IHC practice; UniProt Q12791 isoforms). The supplied PB9227 image caption does not identify that epitope, so it cannot establish coverage of every isoform (PB9227 image caption). If two antibodies disagree, compare their epitope coverage, retrieval conditions, and staining compartments using matched sections (standard IHC practice; UniProt Q12791 topology).
How can IF help assess a disputed KCNMA1 IHC pattern?
Use IF as an orthogonal localisation check and multiplex KCNMA1 with a marker for the expected cell type, such as glandular cells in duodenum, after validating that marker independently (HPA tissue IHC: high in duodenal glandular cells; standard IF practice). Choose fluorophores after inspecting unstained tissue for autofluorescence, and keep single-label controls to assess channel bleed-through (standard IF practice). Match permeabilisation to the antibody epitope: a cytoplasmic epitope needs intracellular access, whereas extracellular accessibility must be assessed for the specimen preparation (UniProt Q12791 topology; standard IF practice). Because the supplied PB9227 caption is a paraffin-section IHC result and gives no IF conditions, optimise IF fixation and permeabilisation empirically (PB9227 image caption; standard IF practice). Compare cellular location rather than raw IF brightness with DAB intensity (standard IHC/IF practice).
What should I check when KCNMA1 staining is widespread and diffuse?
Begin with a no-primary control and inspect whether DAB deposit follows tissue edges, damaged areas, or compartments outside the expected membrane-associated pattern (standard IHC practice; UniProt Q12791: cell membrane). The PB9227 image used 10% goat serum blocking, biotinylated goat anti-rabbit secondary antibody, a streptavidin–biotin complex, and DAB (PB9227 image caption). Check endogenous peroxidase blocking and assess background from the biotin-based detection system with appropriate controls before changing primary concentration (standard IHC practice; PB9227 image caption). If background persists, shorten DAB development or titrate the primary around the documented 1 µg/ml condition while preserving a known positive section (standard IHC practice; PB9227 image caption). Compare signal within matched cell types, since HPA reports both stained and undetected populations across tissues (HPA tissue IHC).
How should I quantify KCNMA1 IHC across tissue sections? ⚠ ANSWER MARKED FOR VERIFICATION
Define the cell type and compartment before scoring, since KCNMA1 is membrane annotated and HPA reports both membranous and cytoplasmic staining (UniProt Q12791: cell membrane; HPA tissue IHC profile). For glandular cells, report the percentage of positive cells and an H-score based on prespecified intensity categories; document whether membrane and cytoplasm were scored separately (standard IHC practice). For discrete positive cells, report counts per mm² of evaluable tissue and normalise to the same tissue compartment or eligible cell population across sections (standard IHC practice). Keep retrieval, exposure to DAB, and image-analysis thresholds consistent, and exclude folds, necrosis, and edge artefacts by a documented rule (standard IHC practice). Do not equate an H-score with channel activity, which also depends on calcium, voltage, and modulatory subunits (UniProt Q12791 function and subunit).
How can I distinguish genuine KCNMA1 staining from artefact?
Give the most weight to reproducible staining in the expected cell type and a plausible membrane-associated pattern, with suitable positive and negative controls (UniProt Q12791: cell membrane; standard IHC practice). HPA reports high staining in duodenal glandular cells but no detected staining in adipocytes, providing cell-specific reference observations rather than universal control guarantees (HPA tissue IHC). Treat isolated nuclear DAB, tissue-edge accentuation, necrotic deposits, or signal in the no-primary control as reasons to investigate artefact (UniProt Q12791: cell membrane; standard IHC practice). Review endogenous peroxidase and biotin-system background when staining is broad, because the PB9227 image used streptavidin–biotin detection with DAB (PB9227 image caption; standard IHC practice). Interpret discordance cautiously: HPA labels its tissue IHC data approved while noting low consistency with RNA and pending external verification (HPA tissue IHC reliability).
Boster reagents
Best KCNMA1 / Calcium-activated potassium channel subunit alpha-1 IHC Antibodies
PB9227 has real KCNMA1 IHC images from paraffin-embedded mouse and rat intestine and human lung cancer tissue (PB9227 IHC captions); no IF image is supplied (catalog: IF images absent).
Real IHC data
Anti-Maxi Potassium channel alpha/KCNMA1 Antibody ®
Cat # PB9227
PB9227 is listed for IHC in human, mouse and rat (catalog: PB9227 applications and reactivity). Its IHC captions show paraffin-embedded mouse and rat intestine and human lung cancer tissue (PB9227 IHC captions).
Which to pick: Choose PB9227 for paraffin-section IHC: its captions document those samples, and the catalog lists an IHC dilution of 0.5–1 μg/ml (PB9227 IHC captions; catalog: PB9227 IHC dilution). PB9227 is the cross-species choice for human, mouse and rat IHC; it is rabbit-hosted, with no clone specified (catalog: PB9227 reactivity, host and clone). No IF/ICC SKU is supported by this payload, and the fixative used for the pictured paraffin sections is unreported (catalog: PB9227 applications and IF images; PB9227 IHC captions).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry Q12791 (KCMA1_HUMAN, Calcium-activated potassium channel subunit alpha-1).
- Human Protein Atlas. KCNMA1 tissue IHC expression (reliability: Approved).
- Human Protein Atlas. KCNMA1 subcellular location (ICC-IF): Membrane.
- Human Protein Atlas. KCNMA1 antibody validation summary (1 antibodies).
- KCNMA1 Expression is Downregulated in Colorectal Cancer via Epigenetic Mechanisms. Cancers 2019 — PMC6406553.
- Metabolomic and transcriptomic signatures of prenatal excessive methionine support nature rather than nurture in schizophrenia pathogenesis. Communications biology 2020 — PMC7393105.
- Transcriptomics reveals age-related changes in ion transport-related factors in yak lungs. Frontiers in veterinary science 2024 — PMC11110679.
- Co-dependent regulation of p-BRAF and potassium channel KCNMA1 levels drives glioma progression. Cellular and molecular life sciences : CMLS 2023 — PMC9918570.
- PubMed PMID:7877450 — UniProt-cited evidence.
- PubMed PMID:7573516 — UniProt-cited evidence.
- PubMed PMID:15164054 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for KCNMA1 (Calcium-activated potassium channel subunit alpha-1). Expected localisation Observed cytoplasmic/membranous (HPA tissue IHC); cell membrane expected (UniProt). Antigen retrieval: Citrate pH 6 HIER, heat-mediated (datasheet PB9227). Validated IHC antibody: PB9227 at 0.5-1μg/ml (the product's own IHC validation image is shown). Controls (HPA): positive Duodenum (Glandular cells); negative Adipose tissue. IHC-P workflow on paraffin sections; fixative unspecified. Protocol steps: 1. Sample: Paraffin-embedded mouse intestine tissue; fixative not specified (datasheet PB9227); 2. Fixation: Image fixative and duration unreported (datasheet PB9227); 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 PB9227); 6. Peroxidase block: 3% H2O2, 10 min , room temperature (standard); 7. Blocking: 10% goat serum (datasheet PB9227); 8. Primary antibody: Rabbit anti-KCNMA1, 0.5-1μg/ml (datasheet PB9227); 9. Primary incubation: Overnight at 4 °C (datasheet PB9227). Watch for: Fixation: Keep fixation consistent across sections (standard IHC practice; not target-specific); Caveat: Low consistency between staining and RNA expression (HPA tissue IHC); Isoform / epitope: 7 isoforms; extracellular versus cytoplasmic epitope matters (UniProt); Regulation: Expression regulation unreported (UniProt). Evidence: UniProt Q12791, HPA tissue IHC · Approved, HPA ICC-IF · Membrane, Datasheet PB9227, PMC6406553, PMC11110679. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/KCNMA1/immunohistochemistry-ihc-guide.