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SDHB / Succinate dehydrogenase [ubiquinone] iron-sulfur subunit, mitochondrial · IHC design guide
Design Immunohistochemistry for SDHB
Plan SDHB chromogenic IHC around granular cytoplasmic staining across cell types (HPA tissue IHC). Use the IHC-validated antibody with tissue controls and score cytoplasmic signal, bearing in mind SDHB’s inner mitochondrial membrane location (UniProt).
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
SDHB 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 | Granular cytoplasm (HPA tissue IHC) | |
| Staining pattern | Granular cytoplasmic staining across cell types (HPA tissue IHC) | |
| Antigen retrieval | Citrate pH 6 HIER, heat-mediated (datasheet M01090-1) | |
| Positive control | Adrenal gland+4 more · see all | |
| Negative control | None in HPA (detected in all 45 tissues); use no-primary + isotype controls |
Important caveats
Reasons your staining may differ from the expected pattern.
| Fixation | Keep fixation conditions consistent across sections (standard IHC practice; not target-specific) | |
| Caveat | Low staining in adipocytes and chondrocytes (HPA tissue IHC) | |
| Regulation | RNA enhanced in skeletal muscle, tongue (HPA tissue RNA) | |
| Isoform / epitope | No isoforms listed; mature chain spans residues 29–280 (UniProt) |
Section 1
Recommended SDHB IHC & IF Protocols
The catalog antibody protocol uses citrate pH 6 heat retrieval (datasheet M01090-1). Three published SDHB IHC protocols provide additional sample, staining and detection details (PMC3415983; PMC4718191; PMC8418866).
| Sample | Paraffin-embedded human lung cancer tissues; fixative not specified (datasheet M01090-1) |
| Fixation | Image fixative and duration unreported (datasheet M01090-1); verify before use. |
| Sectioning | 4–5 µm sections on charged slides (standard) |
| Deparaffinisation | Xylene, graded ethanol series to water (standard) |
| Antigen retrieval | Heat retrieval: Citrate pH 6, 20 min (datasheet M01090-1) |
| Peroxidase block | 3% H2O2, 10 min, room temperature (standard) |
| Blocking | 10% goat serum (datasheet M01090-1) |
| Primary antibody | Mouse monoclonal (clone 2I3) anti-SDHB, 0.5-1μg/ml (datasheet M01090-1) |
| Primary incubation | Overnight at 4 °C (datasheet M01090-1) |
| Detection | Streptavidin-biotin complex (SABC), DAB chromogen (datasheet M01090-1) |
| Counterstain | Hematoxylin, blue, dehydrate and mount (standard) |
| Expected result | SDHB-positive staining in glandular cells of adrenal gland (HPA tissue IHC: High). HPA tissue profile: Granular cytoplasmic expression in all cell types. No signal in the no-primary control. |
💡Decision noteStart with citrate pH 6 heat retrieval (datasheet M01090-1); the published FFPE protocol also used Tris–EDTA pH 9 (PMC4718191).
Section 2
What Is the Expected SDHB Staining Pattern?
SDHB is an inner mitochondrial membrane protein without a transmembrane segment (UniProt P21912 topology). In paraffin-section IHC, expect granular cytoplasmic staining across cell types (HPA: granular cytoplasmic expression in all cell types). HPA rates the tissue IHC profile Enhanced, reflecting high consistency between antibody staining and RNA expression data (HPA: Enhanced reliability). Interpret intensity in the tissue and cell type examined rather than requiring every cell to stain equally.
| Granular cytoplasmic staining in colon glandular cells or bronchial respiratory epithelial cells. | This matches the reported compartment and cells; both examples have High staining (HPA: granular cytoplasmic expression; High in colon glandular and bronchial respiratory epithelial cells). Assess the granules against tissue morphology and nearby background. |
| Predominantly nuclear or cell-edge staining, with little granular cytoplasmic signal. | This differs from the tissue IHC pattern (HPA: granular cytoplasmic expression). Review controls and detection before calling it SDHB. Additional nucleoplasm and plasma membrane locations are uncertain in ICC-IF (HPA: subcellular location); they do not establish an expected paraffin IHC pattern. |
| Strong staining confined to an unexpected cell population while expected cells lack granules. | Treat the distribution as suspicious, not as proof of a new SDHB-positive cell type: HPA describes granular expression in all cell types and gives cell-specific intensity examples (HPA: tissue IHC). Check cross-reactivity and endogenous detection activity using appropriate controls (general IHC practice). |
| Diffuse, uniform color over tissue or blank areas instead of discrete cytoplasmic granules. | Background can obscure the reported pattern (HPA: granular cytoplasmic expression). Compare a no-primary control, inspect wash and blocking steps, and assess whether the detection system contributes color (general IHC practice). Diffuse color alone does not establish SDHB localization. |
| No convincing signal in colon glandular cells despite preserved tissue morphology. | Colon glandular cells are reported High (HPA: colon glandular cells, High). First evaluate the positive control and assay steps; absent staining in one section cannot by itself establish loss of SDHB expression (general IHC practice). |
💡Expected SDHB appearanceCall a positive result when cells show discernible granular cytoplasmic staining, with High signal expected in documented examples such as colon glandular cells (HPA: tissue IHC); predominantly nuclear color or uniform haze is discordant with that pattern (HPA: granular cytoplasmic expression).
| Compartment and topology | SDHB is assigned to the mitochondrial inner membrane and has no transmembrane segment (UniProt P21912 topology). The tissue readout is granular cytoplasmic staining (HPA: tissue IHC); score that visible pattern rather than inferring membrane-surface staining from the protein name. |
| Tissue and cell-type intensity | HPA reports granular cytoplasmic expression in all cell types, with High staining in its listed colon glandular and bronchial respiratory epithelial cells (HPA: tissue IHC). Match an intensity judgment to the cell type on the slide; the examples are observations, not a universal intensity cutoff. |
| Low-staining cell examples | Adipocytes and chondrocytes are listed as Low (HPA: adipocytes, Low; chondrocytes, Low). Weak staining there is less informative as a sole assay control than a documented High cell population (general IHC practice). Low is an intensity category, not evidence of complete absence. |
| Protein processing | UniProt assigns SDHB a mature chain spanning residues 29–280 and lists no isoforms (UniProt P21912 processing and isoforms). These annotations do not specify the antibody epitope or predict whether a particular antigen-retrieval condition will reveal it. |
| Antibody-level validation | HPA rates IHC staining Enhanced for HPA002868, CAB009822 and CAB068235, and Supported for CAB068233 and CAB068234 (HPA: antibody IHC validation). These ratings support review of staining patterns; they do not supply a dilution, retrieval setting or slide-specific performance guarantee. |
| Antigen retrieval | Retrieval is a general paraffin IHC workflow variable (general IHC practice). The supplied HPA and UniProt records give no SDHB-specific retrieval condition or fixation-sensitivity result; optimize with controls before interpreting a weak slide. |
| Situation | Likely cause | Next action |
|---|---|---|
| Known High colon glandular cells show no granular staining. | An assay-step failure is possible; the expected cell-level observation is High (HPA: colon glandular cells, High). The records do not identify a target-specific fixation cause. | Check a documented positive section, reagent sequence, detection and counterstain; review the chosen retrieval condition as general IHC practice. Do not score biological loss until assay performance is established. |
| The section has widespread flat color that hides cell detail. | Excess background or endogenous detection activity may mask the granular cytoplasmic pattern (HPA: tissue IHC; general IHC practice). The appearance alone does not identify which step failed. | Run a no-primary control and review blocking, washes and chromogen development (general IHC practice). Read SDHB only where granules remain distinguishable from background (HPA: granular cytoplasmic expression). |
| A nuclear rim or plasma-membrane outline dominates. | This is discordant with tissue IHC granules (HPA: tissue IHC). HPA labels additional nucleoplasm and plasma membrane ICC-IF locations uncertain (HPA: subcellular location). | Recheck cell morphology, control staining and detection specificity (general IHC practice); avoid treating an uncertain ICC-IF location as confirmation of the chromogenic IHC result. |
| Adipocytes or chondrocytes stain faintly while other cells stain strongly. | Those cell types have Low reported staining (HPA: adipocytes, Low; chondrocytes, Low). Unequal intensity by itself does not imply a failed stain. | Judge the section against its cell types and include a documented High population for comparison (HPA: tissue IHC; general IHC practice). Do not use Low as a required negative result. |
| Only one unexpected cell population is intensely colored. | A restricted pattern conflicts with HPA's granular expression across cell types if expected cells are unstained (HPA: tissue IHC). Cross-reactivity or endogenous detection activity are possible assay explanations (general IHC practice). | Compare morphology and a no-primary control; repeat with another appropriately validated antibody if needed (general IHC practice; HPA: antibody IHC validation). Do not assign a new cell-specific expression pattern from this slide alone. |
| IF/ICC: should mitochondrial puncta be expected? | HPA supports mitochondria as the main ICC-IF location; additional nucleoplasm and plasma membrane locations are uncertain (HPA: subcellular location). This evidence describes localization, not an IF protocol. | Expect a mitochondrial distribution when interpreting IF/ICC (HPA: mitochondria, supported; UniProt P21912 localization). Use the separate IF/ICC guide for experimental setup. |
Experiment evidence
IHC & IF images showing SDHB staining
M01090-1 · IHCIHC analysis of SDHB using anti-SDHB antibody (M01090-1). SDHB was detected in paraffin-embedded section of human lung cancer tissues. Heat
M01090-1 · IHCIHC analysis of SDHB using anti-SDHB antibody (M01090-1). SDHB was detected in paraffin-embedded section of human mammary cancer tissues. He
M01090-2 · IHCIHC analysis of SDHB using anti-SDHB antibody (M01090-2). SDHB was detected in paraffin-embedded section of human intestinal cancer tissues.
M01090-2 · IHCIHC analysis of SDHB using anti-SDHB antibody (M01090-2). SDHB was detected in paraffin-embedded section of human mammary cancer tissues. He
PA1718 · IHCIHC analysis of SDHB using anti-SDHB antibody (PA1718). SDHB was detected in a paraffin-embedded section of human liver cancer tissue. Heat
PA1718 · IHCIHC analysis of SDHB using anti-SDHB antibody (PA1718). SDHB was detected in a paraffin-embedded section of human lung adenocarcinoma tissue
M01090-5 · IHCRat kidney was stained with anti-SDHB rabbit antibody
M01090-5 · IHCHuman kidney was stained with anti-SDHB rabbit antibody
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000117118-SDHB/tissue/cerebral+cortex#imid_18632412
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000117118-SDHB/tissue/colon#imid_18632338
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000117118-SDHB/tissue/liver#imid_18632355
HPA · KidneyHuman Protein Atlas IHC, Kidney. Source: https://www.proteinatlas.org/ENSG00000117118-SDHB/tissue/kidney#imid_18632340
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA002868; green = SDHB, blue = nucleus, red = microtubules.
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA002868; green = SDHB, blue = nucleus, red = microtubules.
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for SDHB IHC & IF
🧪Run adrenal gland first; its glandular cells should stain strongly (HPA: High in adrenal gland glandular cells). HPA detects SDHB in all 45 scored tissues, so there is no supported negative tissue: use no-primary and isotype controls, and expect clear extracellular background rather than a reliably negative cell population within the positive section (HPA: no negative rows; detected in all 45 scored tissues).
Positive control tissue: Adrenal gland (Glandular cells, HPA High)
Negative control tissue: None in HPA: SDHB 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 SDHB in A-431, PC-3, U2OS, with annotated localisation: Mitochondria (supported) (HPA subcellular).
Technical controls: Include a secondary-only slide, an irrelevant mouse IgG control matched to the primary antibody’s isotype and clonality, and SDHB-knockout material as a biological negative (caption: mouse anti-SDHB). For chromogenic detection, check endogenous peroxidase and biotin background because the reported method uses an avidin-biotin complex with DAB (caption: SABC/DAB).
⚠️Feasibility: No target-specific fixation window or fixation effect is reported in the supplied evidence, and the selected M01090-1 tissue-IHC caption does not state a fixative (caption: fixative unreported). The reported paraffin-section method uses citrate retrieval at pH 6 for 20 minutes; whether frozen sections or IF are easier is unreported (caption: citrate retrieval). No adrenal-specific artefact is documented here; assess background from the chosen chromogenic detection method on the adrenal section (HPA: adrenal gland glandular cells High; caption: SABC/DAB).
HPA tissue IHC evidence for SDHB
Comprehensive Human Protein Atlas IHC scoring per tissue (reliability: Enhanced — 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 → |
| Breast | Glandular cells | High | Protein (IHC) | HPA → |
| Bronchus | Respiratory epithelial cells | High | Protein (IHC) | HPA → |
| Caudate | Neuronal cells | High | Protein (IHC) | HPA → |
Undetected expression · recommended negative controls
| Tissue | Cell type | Level | Evidence | Source |
|---|---|---|---|---|
| None in HPA: SDHB is detected in all 45 scored tissues. Use a no-primary (secondary-only) and an isotype control instead. | ||||
Section 3
Advanced SDHB IHC Tips
Use the paraffin-section IHC example and the reported mitochondrial staining pattern to troubleshoot SDHB while keeping unreported processing details explicit.
What should I change when SDHB staining is weak after retrieval?
Start with heat-mediated citrate retrieval at pH 6 for 20 minutes (datasheet M01090-1). The selected paraffin-section example used that condition before overnight incubation with 1 μg/ml primary antibody at 4°C (selected SKU caption). If signal is weak, check heating consistency, section adhesion, and whether the antibody reaches tissue evenly before changing retrieval conditions (standard IHC practice). Compare any adjusted retrieval with the citrate condition on matched sections, judging improvement by granular cytoplasmic staining and preserved tissue structure (HPA tissue IHC profile; standard IHC practice).
Can I attribute absent SDHB staining to the fixative?
Target-specific sensitivity of SDHB staining to fixation is unknown from the supplied evidence (selected SKU caption: fixative not stated). The selected image documents a paraffin-embedded human lung cancer section, but gives no fixative or fixation duration (selected SKU caption). Record those variables for each specimen, and compare suspect sections with an adequately stained section processed alongside them (standard IHC practice). If multiple antigens stain poorly in the same area, examine tissue preservation and processing before assigning the loss specifically to SDHB (standard IHC practice). Do not derive a fixation requirement from SDHB topology or its reported tissue staining pattern (UniProt P21912 topology; HPA tissue IHC profile).
Which staining pattern supports SDHB localisation in paraffin sections?
Look for granular cytoplasmic staining: the tissue IHC profile reports this pattern across cell types (HPA tissue IHC profile). SDHB is associated with the mitochondrial inner membrane and has no annotated transmembrane segment (UniProt P21912 subcellular location and topology). Assess whether granules lie within intact cells and recur away from section edges, where processing artefacts can complicate interpretation (standard IHC practice). Diffuse nuclear staining alone does not match the reported tissue pattern; additional nucleoplasmic and plasma-membrane localisation in the subcellular dataset is marked uncertain (HPA tissue IHC profile; HPA subcellular). Interpret the pattern alongside tissue morphology and a matched control section (standard IHC practice).
Could epitope choice explain a discordant SDHB result?
The supplied record lists 0 annotated isoforms, so an isoform-specific explanation has no support here (UniProt P21912 isoforms). It identifies a processed chain spanning residues 29–280, but supplies no epitope location for the catalog antibody (UniProt P21912 processing; selected SKU caption). The protein has no annotated transmembrane segment and includes iron-sulfur domains at residues 40–133 and 176–206 (UniProt P21912 topology and domains). Acetyllysines at residues 51 and 55 are annotated, but their effect on this antibody's staining is unreported (UniProt P21912 modified residues; selected SKU caption). Compare staining under the documented retrieval condition before proposing an epitope mechanism (datasheet M01090-1; standard IHC practice).
How should I check an SDHB IHC pattern by multiplex IF?
For an IF follow-up, pair SDHB with a marker identifying the expected cell population; respiratory epithelial cells in bronchus have reported high SDHB staining (HPA tissue IHC). Select spectrally separated fluorophores and consider a longer-wavelength channel where tissue autofluorescence obscures signal, using single-label controls to assess bleed-through (standard IF practice). Test permeabilisation for access to the mitochondrial inner-membrane-associated antigen, since the supplied topology gives no epitope position or membrane-facing side for this antibody (UniProt P21912 topology; selected SKU caption). Compare intracellular puncta with a mitochondrial reference and inspect each channel separately before interpreting overlap (HPA subcellular; standard IF practice).
How do I reduce diffuse or patchy chromogenic background?
First compare the stain with a no-primary control to distinguish detection-system background from primary-antibody signal (standard IHC practice). The selected example used 10% goat serum blocking, 1 μg/ml primary antibody overnight at 4°C, and a biotinylated secondary for 30 minutes at 37°C (selected SKU caption). Check peroxidase blocking, washing, and DAB development as general chromogenic workflow variables, particularly where tissue pigmentation complicates reading (standard IHC practice). Retain a condition that resolves discrete granular cytoplasmic staining without raising diffuse signal across the section (HPA tissue IHC profile; standard IHC practice).
How should I score SDHB staining across sections? ⚠ ANSWER MARKED FOR VERIFICATION
Define the cell population and analysis region before scoring, excluding necrosis and poorly preserved edges consistently (standard IHC practice). An H-score sums the percentage of cells at intensity grades 0–3 multiplied by each grade, giving a 0–300 range (standard IHC practice). Report the percentage of positive cells separately when extent matters, and keep the positivity threshold and DAB exposure comparable across sections (standard IHC practice). Normalise any stained-area or positive-cell density per mm² to evaluable tissue area or the relevant cell population, and document how background was subtracted (standard IHC practice).
When is an apparent SDHB-positive stain likely to be artefact?
A credible positive shows granular cytoplasmic staining within preserved cells, consistent with the reported tissue pattern and mitochondrial localisation (HPA tissue IHC profile; UniProt P21912 subcellular location). Treat staining confined to a section edge, necrotic area, or morphologically inappropriate material cautiously, and compare it with intact nearby cells (standard IHC practice). Nuclear-only or surface-only staining is discordant with the main supported mitochondrial location; the reported nucleoplasmic and plasma-membrane locations are uncertain (HPA subcellular). Check a no-primary control for endogenous enzyme or detection background, especially before calling broad DAB deposition positive (standard IHC practice). A technically adequate negative result alone does not establish why SDHB signal is absent (standard IHC practice).
Boster reagents
Best SDHB / Succinate dehydrogenase [ubiquinone] iron-sulfur subunit, mitochondrial IHC Antibodies
Anti-SDHB IHC images cover human cancer tissues and rat kidney (catalog IHC captions: M01090-1, M01090-2, PA1718, M01090-5); an IF/ICC image shows U20S cells (A01090 IF caption).
Real IHC data
Anti-SDHB Antibody ® (monoclonal, 2I3)
Cat # M01090-1
Real IHC data
Anti-SDHB Antibody ® (monoclonal, 11I3)
Cat # M01090-2
Real IHC data
Anti-SDHB Antibody ®
Cat # PA1718
Real IHC data
Anti-SDHB Rabbit Monoclonal Antibody
Cat # M01090-5
M01090-1 shows human lung cancer, and M01090-2 shows human intestinal cancer in paraffin sections (catalog IHC captions: M01090-1, M01090-2). PA1718 shows paraffin-section human liver cancer, while M01090-5 shows rat kidney (catalog IHC captions: PA1718, M01090-5).
Which to pick: For tissue IHC, choose mouse monoclonal M01090-1 for human lung cancer with citrate retrieval, M01090-2 for human intestinal cancer with citrate retrieval, or PA1718 for human liver cancer with EDTA retrieval (catalog IHC captions: M01090-1, M01090-2, PA1718; catalog clones: M01090-1, M01090-2). For IF/ICC, consider rabbit monoclonal M01090-5 because IF is listed at 1:200–1:1000; its supplied image captions document IHC rather than IF (M01090-5 application list, dilution and image captions). For cross-species tissue IHC, M01090-5 has human, mouse and rat kidney images; the four rendered IHC captions do not report the fixative (M01090-5 image captions; catalog IHC captions: M01090-1, M01090-2, PA1718, M01090-5).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry P21912 (SDHB_HUMAN, Succinate dehydrogenase [ubiquinone] iron-sulfur subunit, mitochondrial).
- Human Protein Atlas. SDHB tissue IHC expression (reliability: Enhanced).
- Human Protein Atlas. SDHB subcellular location (ICC-IF): Mainly localized to the mitochondria. In addition localized to the nucleoplasm and plasma membrane..
- Human Protein Atlas. SDHB antibody validation summary (5 antibodies).
- Alpha-ketoglutarate alleviates acute pancreatitis by restoring energy metabolism. iScience 2026 — PMC13059122.
- SDHB immunohistochemistry: a useful tool in the diagnosis of Carney-Stratakis and Carney triad gastrointestinal stromal tumors. Modern pathology : an official journal of the United States and Canadian Academy of Pathology, Inc 2011 — PMC3415983.
- An immunohistochemical procedure to detect patients with paraganglioma and phaeochromocytoma with germline SDHB, SDHC, or SDHD gene mutations: a retrospective and prospective analysis. The Lancet. Oncology 2009 — PMC4718191.
- Succinate Dehydrogenase Complex Iron Sulfur Subunit B (SDHB) Immunohistochemistry in Pheochromocytoma, Head and Neck Paraganglioma, Thoraco-Abdomino-Pelvic Paragangliomas: Is It a Good Idea to Use in Routine Work?. Asian Pacific journal of cancer prevention : APJCP 2021 — PMC8418866.
- PubMed PMID:7622059 — UniProt-cited evidence.
- PubMed PMID:14702039 — UniProt-cited evidence.
- PubMed PMID:16710414 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for SDHB (Succinate dehydrogenase [ubiquinone] iron-sulfur subunit, mitochondrial). Expected localisation Granular cytoplasm (HPA tissue IHC). Antigen retrieval: Citrate pH 6 HIER, heat-mediated (datasheet M01090-1). Validated IHC antibody: M01090-1 at 0.5-1μg/ml (the product's own IHC validation image is shown). Controls (HPA): positive Adrenal gland (Glandular cells); negative None in HPA (detected in all 45 tissues); use no-primary + isotype controls. IHC-P workflow on paraffin sections; fixative unspecified. Protocol steps: 1. Sample: Paraffin-embedded human lung cancer tissues; fixative not specified (datasheet M01090-1); 2. Fixation: Image fixative and duration unreported (datasheet M01090-1); verify before use.; 3. Sectioning: 4–5 µm sections on charged slides (standard); 4. Deparaffinisation: Xylene, graded ethanol series to water (standard); 5. Antigen retrieval: Heat retrieval: Citrate pH 6 , 20 min (datasheet M01090-1); 6. Peroxidase block: 3% H2O2, 10 min , room temperature (standard); 7. Blocking: 10% goat serum (datasheet M01090-1); 8. Primary antibody: Mouse monoclonal (clone 2I3) anti-SDHB, 0.5-1μg/ml (datasheet M01090-1); 9. Primary incubation: Overnight at 4 °C (datasheet M01090-1). Watch for: Fixation: Keep fixation conditions consistent across sections (standard IHC practice; not target-specific); Caveat: Low staining in adipocytes and chondrocytes (HPA tissue IHC); Isoform / epitope: No isoforms listed; mature chain spans residues 29–280 (UniProt); Regulation: RNA enhanced in skeletal muscle, tongue (HPA tissue RNA). Evidence: UniProt P21912, HPA tissue IHC · Enhanced, HPA ICC-IF · Mainly localized to the mitochondria. In addition localized to the…, Datasheet M01090-1, PMC3415983, PMC4718191. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/SDHB/immunohistochemistry-ihc-guide.