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SRRM2 / Serine/arginine repetitive matrix protein 2 · IHC design guide
Design Immunohistochemistry for SRRM2
Plan chromogenic IHC for SRRM2 using its ubiquitous nuclear tissue pattern (HPA tissue IHC). Compare nuclear staining across cells with consistent fixation, and check whether the antibody epitope covers the 3 reported isoforms (UniProt).
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
SRRM2 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 tissue staining (HPA tissue IHC) | |
| Staining pattern | Ubiquitous nuclear staining (HPA tissue IHC) | |
| Antigen retrieval | Tris-EDTA pH 9.0 HIER, heat-mediated (datasheet A07592) | |
| 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) | |
| Caveat | Broad nuclear staining limits tissue specificity (HPA tissue IHC) | |
| Regulation | Low tissue specificity (HPA tissue RNA) | |
| Isoform / epitope | 3 isoforms; check antibody epitope coverage (UniProt) |
Section 1
Recommended SRRM2 IHC & IF Protocols
The catalog antibody protocol uses Tris-EDTA pH 9.0 retrieval (datasheet A07592). These published IHC protocols provide three tissue-specific comparisons (PMC10827842; PMC13319659; PMC11502262).
| Sample | Paraffin-embedded human Small intestinal stromal tumor tissue; fixative not specified (datasheet A07592) |
| Fixation | Image fixative and duration unreported (datasheet A07592); verify before use. |
| Sectioning | 4–5 µm sections on charged slides (standard) |
| Deparaffinisation | Xylene, graded ethanol series to water (standard) |
| Antigen retrieval | Heat retrieval: Tris-EDTA pH 9.0 (datasheet A07592); 20 min, 95–100 °C (standard) |
| 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-SRRM2, 1:50 (datasheet A07592) |
| 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 | SRRM2-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 Tris-EDTA pH 9.0 for the catalog antibody (datasheet A07592); evaluate citrate pH 6.0 if staining needs optimization (PMC10827842; PMC13319659; PMC11502262).
Section 2
What Is the Expected SRRM2 Staining Pattern?
SRRM2 should produce nuclear staining in many cell types in paraffin sections (HPA: ubiquitous nuclear expression; UniProt Q9UQ35: nucleus and nuclear speckle). HPA reports high staining in glandular, hematopoietic, respiratory epithelial, neuronal and glial cells across its listed tissues, with supported IHC reliability based on agreement with RNA expression (HPA: tissue IHC, Supported). SRRM2 has no transmembrane segment (UniProt Q9UQ35: topology).
| Nuclear signal in glandular cells of appendix or adrenal gland, or hematopoietic cells of bone marrow. | This fits the reported distribution: each listed population has High HPA tissue staining (HPA: tissue IHC). Score nuclei within the identified cell population; compare intensity and the fraction of positive nuclei within that population. A positive control supports interpretation of the assay, but does not prove that every stained cell in a test section is specific. |
| Strong cytoplasmic, membranous or extracellular deposit dominates while nuclei are weak or blank. | The dominant compartment conflicts with the nuclear assignment (UniProt Q9UQ35: nucleus; HPA: ubiquitous nuclear expression). Treat the deposit as possible nonspecific staining or detection artefact. Recheck morphology, run the appropriate detection controls and assess whether any convincing nuclear signal remains before calling the section SRRM2 positive. |
| Signal is confined to a cell population outside the listed HPA examples while expected nuclei in the same section are blank. | The pattern warrants review for antibody cross-reactivity or endogenous detection activity. HPA reports low tissue specificity and ubiquitous nuclear expression, so an unlisted cell type is not automatically negative (HPA: tissue IHC). The concern is the combined compartment and control pattern, rather than the cell name alone. |
| Widespread diffuse color obscures nuclei, tissue edges or blank spaces. | Background can make a nuclear result uninterpretable. General IHC practice is to inspect the no-primary control, blocking and washes, then shorten chromogen development or reduce detection strength if needed. HPA supports a nuclear target pattern, but does not identify the cause of background in this preparation (HPA: tissue IHC). |
| No nuclear signal appears in a control tissue expected to stain strongly. | A blank appendix glandular compartment or bone marrow hematopoietic compartment conflicts with HPA High staining in those cells (HPA: tissue IHC). First assess tissue preservation, cell identity and the assay controls; then review antibody application, retrieval and detection as general IHC variables. A blank run alone cannot establish absent SRRM2 expression. |
💡Expected SRRM2 appearanceCall a convincing positive result when identifiable cells show predominantly nuclear signal, potentially strong in HPA-listed high-staining populations; dominant cytoplasmic or extracellular color without matching nuclear signal is suspicious (HPA: tissue IHC; UniProt Q9UQ35: nucleus).
| Tissue and cell selection | HPA reports High staining in adrenal and appendix glandular cells, bone marrow hematopoietic cells, bronchial respiratory epithelium, caudate neuronal cells and cerebral cortex glial cells (HPA: tissue IHC). Use an identified listed population for a positive-control readout. These examples do not define exclusive expression or a validated negative tissue (HPA: low tissue specificity; negative list empty). |
| Antibody evidence | HPA041411 has Supported IHC status; HPA066181 has no IHC status in the supplied record (HPA: antibodies). HPA's tissue profile is also Supported, reflecting agreement with RNA expression (HPA: tissue IHC). Keep these evidence levels separate: an ICC result alone does not establish performance in paraffin sections. |
| Isoforms and epitope | UniProt lists three SRRM2 isoforms and a full-length chain spanning residues 1–2752 (UniProt Q9UQ35: isoforms and processing). The supplied sources do not locate the IHC antibody epitope or show which isoforms it detects. If samples disagree, review the antibody's stated immunogen before attributing the difference to an isoform. |
| Topology and processing | SRRM2 is assigned to the nucleus and nuclear speckle, with no transmembrane segment, signal peptide or propeptide annotated (UniProt Q9UQ35: location, topology and processing). Those annotations support a nuclear readout; they do not establish how fixation or retrieval affects this antibody, or justify interpreting a membrane rim as the expected signal. |
| IF/ICC: what should the pattern look like? | HPA describes enhanced nuclear speckle localization in ICC-IF; both listed antibodies have Enhanced ICC status (HPA: subcellular; HPA: antibodies). Speckles provide a localization cross-check. Assess paraffin chromogenic sections by their nuclear staining pattern and morphology (HPA: tissue IHC); this IF/ICC observation is not an IF protocol recommendation. |
| Situation | Likely cause | Next action |
|---|---|---|
| Known-positive tissue is blank. | Possible assay failure, unsuitable section or missed positive cell population; HPA lists High staining in appendix glandular and bone marrow hematopoietic cells (HPA: tissue IHC). | Confirm the relevant cells are present, examine a run control and check antibody application, retrieval and detection using general IHC practice. Repeat the run before interpreting a test section as truly negative. |
| Color is mainly cytoplasmic or outlines cell membranes. | The compartment disagrees with the reported nuclear location (UniProt Q9UQ35: location; HPA: tissue IHC). Nonspecific primary binding or detection artefact is possible. | Compare with a no-primary control, inspect nuclear counterstain and tissue morphology, and review the antibody's IHC evidence. Count only convincing nuclear staining as the expected readout. |
| Only an unexpected cell population stains. | Cross-reactivity or endogenous detection activity is possible, especially if an HPA-listed high-staining population on the section is blank (HPA: tissue IHC). HPA's low tissue specificity means cell identity alone is insufficient to reject a nuclear signal. | Check the no-primary control and compartment, then compare an HPA-listed positive population. Investigate detection activity and antibody specificity before assigning the signal to SRRM2. |
| Diffuse deposit prevents scoring nuclei. | General IHC background may arise from detection activity, inadequate blocking or excessive development; the supplied HPA and UniProt records do not identify a cause for this specimen. | Inspect no-primary and detection controls, review blocking and washes, and adjust chromogen development or detection strength as appropriate. Re-score only when nuclear boundaries are readable. |
| A strong nuclear signal varies between tissue types. | Cell composition and expression may differ: HPA reports low tissue specificity but identifies particular cell populations with High staining (HPA: tissue IHC). Variation alone does not establish an assay fault. | Compare the same cell types and scoring criteria, verify tissue identity, and include an HPA-listed positive control. Report intensity and proportion of positive nuclei separately. |
| ICC shows speckles, but paraffin-section staining looks less punctate. | HPA's enhanced nuclear speckle result comes from ICC-IF, whereas its tissue result describes ubiquitous nuclear IHC staining (HPA: subcellular; HPA: tissue IHC). The supplied evidence does not require identical visual detail across methods. | For IHC, judge nuclear localization, identifiable positive cells and assay controls. Use the ICC-IF finding as a localization cross-check; consult the separate IF/ICC guide for that application. |
Experiment evidence
IHC & IF images showing SRRM2 staining
A07592 · IHCImmunohistochemical analysis of paraffin-embedded human Small intestinal stromal tumor. 1, Tris-EDTA, pH9.0 was used for antigen retrieval.
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000167978-SRRM2/tissue/cerebral+cortex#imid_10915914
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000167978-SRRM2/tissue/colon#imid_10556383
HPA · RectumHuman Protein Atlas IHC, Rectum. Source: https://www.proteinatlas.org/ENSG00000167978-SRRM2/tissue/rectum#imid_10556367
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000167978-SRRM2/tissue/liver#imid_10556392
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA041411; green = SRRM2, blue = nucleus, red = microtubules.
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA041411; green = SRRM2, blue = nucleus, red = microtubules.
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for SRRM2 IHC & IF
🧪Run bone marrow first: hematopoietic cells should show nuclear staining (HPA: High in hematopoietic cells; UniProt Q9UQ35: nucleus and nuclear speckles). HPA detects SRRM2 in all 45 scored tissues, so there is no validated negative tissue or negative cell population within the positive slide; cells lacking nuclear chromogen can be noted, but no-primary and isotype controls must establish background (HPA: no negative tissue rows; standard IHC practice).
Positive control tissue: Adrenal gland (Glandular cells, HPA High)
Negative control tissue: None in HPA: SRRM2 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 SRRM2 in A-431, U-251MG, U2OS, HEK293, HeLa, U2OS, siRNA 1 (10x), U2OS, siRNA 1 (40x), U2OS, siRNA 2 (10x), U2OS, siRNA 2 (40x), U2OS, scrambled (10x), U2OS, scrambled (40x), with annotated localisation: Nuclear speckles (enhanced) (HPA subcellular).
Technical controls: Include a no-primary, secondary-only control, an isotype control matched to the primary antibody’s host species and immunoglobulin class or clonality, and a target-depleted biological control such as knockout material or a validated peptide block (standard IHC practice). In bone marrow, quench endogenous peroxidase and assess pigment or other background before interpreting chromogenic signal (standard IHC practice).
⚠️Feasibility: No target-specific fixation window or fixation effect is reported, and the selected A07592 paraffin-section caption does not state a fixative (selected-SKU tissue-IHC caption). That caption reports Tris-EDTA retrieval at pH 9.0 and primary antibody at 1:200 overnight at 4°C; whether SRRM2 staining depends on that retrieval condition is unreported (selected-SKU tissue-IHC caption). HPA ICC-IF images support nuclear-speckle localization, but the supplied evidence does not establish that IF or frozen sections are easier than paraffin IHC; bone marrow pigment and endogenous peroxidase can complicate chromogenic interpretation (HPA: nuclear speckles; standard IHC practice).
HPA tissue IHC evidence for SRRM2
Comprehensive Human Protein Atlas IHC scoring per tissue (reliability: Supported — High 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 → |
| Appendix | Glandular cells | High | Protein (IHC) | HPA → |
| Bone marrow | Hematopoietic cells | High | Protein (IHC) | HPA → |
| Breast | Glandular cells | High | Protein (IHC) | HPA → |
| Bronchus | Respiratory epithelial cells | High | Protein (IHC) | HPA → |
Undetected expression · recommended negative controls
| Tissue | Cell type | Level | Evidence | Source |
|---|---|---|---|---|
| None in HPA: SRRM2 is detected in all 45 scored tissues. Use a no-primary (secondary-only) and an isotype control instead. | ||||
Section 3
Advanced SRRM2 IHC Tips
Use nuclear staining as the reference pattern when troubleshooting SRRM2 in paraffin sections (UniProt Q9UQ35; HPA tissue IHC).
How should I adjust retrieval when SRRM2 nuclear staining is weak?
Use heat-mediated Tris-EDTA at pH 9.0 for paraffin sections, matching the selected antibody's tissue image (datasheet A07592). That image used 1:200 primary antibody at 4 °C overnight and 1:200 secondary antibody for 45 minutes at room temperature (caption A07592). Keep heating and cooling consistent across slides, since uneven retrieval can produce uneven staining (standard IHC practice). If signal remains weak, compare shorter and longer heating exposures on adjacent sections while holding antibody dilution and detection constant (standard IHC practice). Judge improvement by distinct nuclear staining, consistent with SRRM2 localisation, rather than diffuse cytoplasmic colour (UniProt Q9UQ35; HPA subcellular).
Could fixation explain weak or patchy SRRM2 staining?
The paraffin-section caption does not state a fixative, so SRRM2-specific sensitivity to fixation is unknown (caption A07592). Record fixation conditions for each specimen, including fixative, duration and any processing delays, before comparing staining across cases (standard IHC practice). Compare sections processed together and stain them in the same run to reduce variation unrelated to the specimen (standard IHC practice). When signal is patchy, examine section integrity and compare neighbouring intact regions before changing retrieval or antibody concentration (standard IHC practice). Treat any association between fixation history and SRRM2 signal as a finding to test with controlled specimens, rather than an established target-specific effect (caption A07592).
What staining pattern should count as SRRM2 positive in tissue?
Score SRRM2 primarily in nuclei: UniProt places it in the nucleus and nuclear speckles, while HPA reports ubiquitous nuclear tissue staining (UniProt Q9UQ35; HPA tissue IHC). HPA reports high staining in adrenal glandular cells and bone marrow hematopoietic cells, so compare the relevant cell population rather than the whole section (HPA tissue IHC). Chromogenic sections may show nuclear staining without resolving individual speckles; assess subnuclear detail only when image resolution supports it (standard IHC practice; HPA subcellular). Strong cytoplasmic colour without corresponding nuclear signal warrants a background check before scoring (UniProt Q9UQ35; standard IHC practice). Include intact nuclei in the assessment and keep the scoring threshold consistent across specimens (standard IHC practice).
Could SRRM2 isoforms or modifications change what the antibody detects?
SRRM2 has 3 annotated isoforms, but the supplied tissue-image caption does not identify this antibody's epitope or isoform coverage (UniProt Q9UQ35; caption A07592). Consequently, a negative nucleus cannot be assigned to loss of a particular isoform from this stain alone (UniProt Q9UQ35; standard IHC interpretation). UniProt lists numerous modified residues, including phosphoserine at residue 220, without establishing their effect on this antibody's binding (UniProt Q9UQ35). Check epitope documentation before comparing antibodies directed at different SRRM2 regions (standard IHC practice). If antibodies disagree, compare their nuclear patterns on adjacent sections under matched processing conditions before proposing an isoform or modification effect (UniProt Q9UQ35; standard IHC practice).
How can IF help assess an ambiguous chromogenic SRRM2 pattern?
Use IF as a separate localisation check: SRRM2 is nuclear, with enrichment in nuclear speckles reported by HPA (UniProt Q9UQ35; HPA subcellular). For multiplexing, pair SRRM2 with a cell-type marker appropriate to the compartment being assessed, such as cytokeratin for glandular epithelium (HPA tissue IHC; standard IF practice). Choose a spectrally separated, preferably far-red SRRM2 fluorophore when tissue autofluorescence interferes with shorter wavelengths (standard IF practice). Because the expected epitope is intracellular and nuclear, optimise permeabilisation for nuclear antibody access after fixation (UniProt Q9UQ35; standard IF practice). Compare nuclear signal with a DNA counterstain and include single-colour controls to distinguish true overlap from channel bleed-through (standard IF practice).
What should I check when the SRRM2 DAB stain looks diffuse?
First inspect a no-primary control and the tissue's unstained appearance to separate detection background from pigment or tissue colour (standard IHC practice). Block endogenous peroxidase before horseradish-peroxidase detection, and keep DAB development time consistent across slides (standard chromogenic IHC practice). Titrate the primary antibody around the image's 1:200 dilution if diffuse signal persists, comparing adjacent sections in one run (caption A07592; standard IHC practice). Assess whether colour follows nuclei, since SRRM2 is reported in the nucleus and nuclear speckles (UniProt Q9UQ35; HPA subcellular). Exclude folds, damaged edges and necrotic areas when judging whether a change improves specific staining (standard IHC practice).
How should I quantify SRRM2 staining across tissue sections? ⚠ ANSWER MARKED FOR VERIFICATION
Define the cell population and score only intact nuclei within that compartment, because HPA describes SRRM2 tissue expression as ubiquitous and nuclear (HPA tissue IHC; standard IHC practice). Report the percentage of positive nuclei and an intensity-stratified nuclear H-score from 0–300, using one threshold across the comparison (standard IHC practice). Normalise positive counts to all assessable nuclei in the same compartment, or report positive-cell density per mm² of viable tissue (standard IHC practice). Exclude necrosis, folds and section edges using predefined criteria before counting (standard IHC practice). Keep counterstain and DAB exposure comparable, and review automated nuclear segmentation against representative images (standard IHC practice).
How can I distinguish genuine SRRM2 staining from artefact?
A credible positive pattern is nuclear, consistent with SRRM2's nuclear-speckle localisation and HPA's ubiquitous nuclear tissue profile (UniProt Q9UQ35; HPA tissue IHC; HPA subcellular). Compare the stained cells with the compartment being evaluated; HPA reports high staining in glandular and hematopoietic populations among its tissue examples (HPA tissue IHC). Colour concentrated at section edges, folds or necrotic regions calls for inspection of tissue quality and processing before interpretation (standard IHC practice). Predominantly cytoplasmic colour is discordant with the supplied localisation evidence and merits a background-control comparison (UniProt Q9UQ35; HPA subcellular; standard IHC practice). If a no-primary control also develops colour, investigate endogenous enzyme activity or detection reagents before calling the specimen positive (standard IHC practice).
Boster reagents
Best SRRM2 / Serine/arginine repetitive matrix protein 2 IHC Antibodies
A07592 is listed for human and mouse IHC and IF (catalog: A07592 applications/reactivity); its IHC figure shows a paraffin-embedded human small intestinal stromal tumor (A07592 IHC caption).
Real IHC data
Anti-SRRM2 Antibody
Cat # A07592
A07592 is the only card and has IHC and IF listed for human and mouse samples (catalog: A07592 applications/reactivity). Its available figure documents IHC on a paraffin-embedded human small intestinal stromal tumor; no IF figure is supplied (A07592 image captions).
Which to pick: Choose A07592 for paraffin-section tissue IHC because its own figure documents that preparation, with Tris-EDTA retrieval at pH 9.0 and primary antibody at 1:200 overnight at 4°C (A07592 IHC caption); the fixative is unreported (A07592 IHC caption). For IF, A07592 is listed, but ICC is not listed and no IF figure is supplied (catalog: A07592 applications/image captions). For cross-species work, A07592 lists human and mouse reactivity and a rabbit host; the supplied image documents human tissue only, and clonality is unreported (catalog: A07592 reactivity/host/clone; A07592 IHC caption).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry Q9UQ35 (SRRM2_HUMAN, Serine/arginine repetitive matrix protein 2).
- Human Protein Atlas. SRRM2 tissue IHC expression (reliability: Supported).
- Human Protein Atlas. SRRM2 subcellular location (ICC-IF): Localized to the nuclear speckles..
- Human Protein Atlas. SRRM2 antibody validation summary (2 antibodies).
- SRRM2 may be a potential biomarker and immunotherapy target for multiple myeloma: a real-world study based on flow cytometry detection. Clinical and experimental medicine 2024 — PMC10827842.
- The intellectual disability gene PQBP1 rescues Alzheimer's disease pathology. Molecular psychiatry 2018 — PMC6250680.
- Nuclear Speckle Protein SRRM2 Co-localized with Pathological Tau (pTauS396) in Neuronal and Glial Cells in Progressive Supranuclear Palsy. Acta histochemica et cytochemica 2026 — PMC13319659.
- Disruption of nuclear speckle integrity dysregulates RNA splicing in C9ORF72-FTD/ALS. Neuron 2024 — PMC11502262.
- PubMed PMID:11004489 — UniProt-cited evidence.
- PubMed PMID:10668804 — UniProt-cited evidence.
- PubMed PMID:9205841 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for SRRM2 (Serine/arginine repetitive matrix protein 2). Expected localisation Nuclear tissue staining (HPA tissue IHC). Antigen retrieval: Tris-EDTA pH 9.0 HIER, heat-mediated (datasheet A07592). Validated IHC antibody: A07592 at 1:50 (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 workflow; specimen preparation unspecified. Protocol steps: 1. Sample: Paraffin-embedded human Small intestinal stromal tumor tissue; fixative not specified (datasheet A07592); 2. Fixation: Image fixative and duration unreported (datasheet A07592); 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: Tris-EDTA pH 9.0 (datasheet A07592); 20 min, 95–100 °C (standard); 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-SRRM2, 1:50 (datasheet A07592); 9. Primary incubation: Overnight at 4 °C (standard). Watch for: Fixation: Keep fixation consistent across sections. (standard IHC practice; not target-specific); Caveat: Broad nuclear staining limits tissue specificity (HPA tissue IHC); Isoform / epitope: 3 isoforms; check antibody epitope coverage (UniProt); Regulation: Low tissue specificity (HPA tissue RNA). Evidence: UniProt Q9UQ35, HPA tissue IHC · Supported, HPA ICC-IF · nuclear speckles., Datasheet A07592, PMC10827842, PMC13319659. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/SRRM2/immunohistochemistry-ihc-guide.