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ASS1 / Argininosuccinate synthase · IHC design guide
Design Immunohistochemistry for ASS1
ASS1 shows cytoplasmic staining in several tissues, including liver and kidney (HPA tissue IHC). Use this guide to plan paraffin-section staining around the catalog antibody’s IHC evidence (datasheet M02212-1) and cell-specific controls (standard IHC practice).
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
ASS1 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 | Cytoplasmic tissue staining (HPA tissue IHC); cytosolic protein (UniProt) | |
| Staining pattern | Cytoplasmic staining in hepatocytes and urothelial cells (HPA tissue IHC) | |
| Antigen retrieval | EDTA pH 8.0 HIER, heat-mediated (datasheet M02212-1) | |
| Positive control | Kidney+4 more · see all | |
| Negative control | Bone marrow+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 | Staining and RNA show medium consistency (HPA tissue IHC) | |
| Regulation | Expression regulation not reported (UniProt) | |
| Isoform / epitope | No annotated isoforms; one 1–412 chain (UniProt) |
Section 1
Recommended ASS1 IHC & IF Protocols
The catalog antibody’s IHC-P protocol (datasheet: M02212-1) is accompanied by published ASS1 IHC methods for esophageal, pancreatic and ovarian tumor samples (PMC12650347; PMC5302782; PMC4858122).
| Sample | Paraffin-embedded human prostate cancer tissue; fixative not specified (datasheet M02212-1) |
| Fixation | Image fixative and duration unreported (datasheet M02212-1); verify before use. |
| Sectioning | 4–5 µm sections on charged slides (standard) |
| Deparaffinisation | Xylene, graded ethanol series to water (standard) |
| Antigen retrieval | Heat retrieval: EDTA pH 8.0 (datasheet M02212-1); 20 min, 95–100 °C (standard) |
| Peroxidase block | 3% H2O2, 10 min, room temperature (standard) |
| Blocking | 10% goat serum (datasheet M02212-1) |
| Primary antibody | Mouse monoclonal (clone 5I5) anti-ASS1, 2μg/ml (datasheet M02212-1) |
| Primary incubation | Overnight at 4 °C (datasheet M02212-1) |
| Detection | Streptavidin-biotin complex (SABC), DAB chromogen (datasheet M02212-1) |
| Counterstain | Hematoxylin, blue, dehydrate and mount (standard) |
| Expected result | ASS1-positive staining in bowman's capsule of kidney (HPA tissue IHC: High). HPA tissue profile: Cytoplasmic expression in several tissues including kidney, liver and urinary bladder. No signal in the no-primary control. |
💡Decision noteStart with heat-mediated EDTA pH 8.0 retrieval for the catalog antibody (datasheet: M02212-1); the cited articles do not specify retrieval conditions (PMC12650347; PMC5302782; PMC4858122).
Section 2
What Is the Expected ASS1 Staining Pattern?
ASS1 is a cytosolic protein with no transmembrane segment (UniProt P00966: subcellular location and topology). In paraffin sections, expect cytoplasmic staining in hepatocytes and cells of Bowman’s capsule; both are reported as high in HPA tissue IHC (HPA: liver and kidney). HPA rates the tissue profile Enhanced but describes only medium consistency between staining and RNA expression (HPA: tissue reliability).
| Strong cytoplasmic staining in hepatocytes or cells of Bowman’s capsule. | This matches the expected compartment and two reported high-staining cell populations (UniProt P00966: cytosol; HPA: liver and kidney, High). Judge the pattern within the identified cells, since an entire tissue need not stain uniformly. |
| Predominantly nuclear, membranous or extracellular staining in an IHC section. | These are unexpected dominant patterns for cytosolic ASS1 (UniProt P00966: subcellular location and no transmembrane segment). Check morphology and detection controls before assigning them to ASS1; HPA’s uncertain additional nucleoplasmic ICC-IF location does not establish a dominant nuclear IHC pattern (HPA: subcellular). |
| Prominent staining of hematopoietic cells in bone marrow or germinal center cells in lymph node. | HPA reports ASS1 as not detected in those specific cell populations (HPA: bone marrow and lymph node). Consider cross-reactivity or endogenous detection activity, and compare with a high-staining control; the HPA observations do not prove absolute absence in every sample. |
| Broad color deposit over stroma, empty spaces or most cell types, obscuring cytoplasm. | This cannot be scored confidently as cell-specific ASS1 staining. Uneven detection background, endogenous activity or insufficient blocking are general IHC possibilities (standard IHC practice); HPA reports a cytoplasmic pattern in several tissues (HPA: tissue profile). |
| No visible signal in hepatocytes or cells of Bowman’s capsule. | A run with no signal in these reported high-staining cells needs technical review before a negative ASS1 call (HPA: liver and kidney, High). Check section integrity and controls, then examine retrieval, antibody exposure and detection as general IHC workflow variables (standard IHC practice). |
💡Expected ASS1 appearanceCall a convincing positive result when clear cytoplasmic color is present in hepatocytes or cells of Bowman’s capsule at a strong level consistent with HPA’s High category (UniProt P00966: cytosol; HPA: liver and kidney); dominant nuclear, membranous or noncellular color warrants investigation rather than a positive call (UniProt P00966: topology; standard IHC practice).
| Cell-specific tissue distribution | HPA reports High staining in hepatocytes, cells of Bowman’s capsule, type II alveolar cells, basal-layer skin cells and urothelial cells (HPA: tissue IHC). Choose and score the named cell population; HPA also reports Medium, Low and Not detected results elsewhere (HPA: tissue IHC). |
| Compartment and topology | Cytoplasmic IHC signal fits a cytosolic protein lacking a transmembrane segment or signal peptide (UniProt P00966: location, topology and processing). These annotations give no basis for expecting a surface or secreted staining pattern. |
| Strength of pattern evidence | HPA calls the tissue profile Enhanced while describing medium agreement with RNA; both listed antibodies have Enhanced IHC status (HPA: tissue reliability and antibody validation). These labels support pattern review, but do not guarantee identical intensity in every section. |
| Antigen retrieval | Retrieval conditions can be assessed with positive and negative controls as a general paraffin IHC workflow step (standard IHC practice). Neither HPA nor UniProt here supplies an ASS1-specific retrieval setting or fixation-sensitivity claim. |
| Epitope interpretation | UniProt lists modified residues, but the supplied record gives no antibody epitope or modification-dependent staining result (UniProt P00966: modified residues). Do not attribute a weak section to a particular modification without separate evidence. |
| Situation | Likely cause | Next action |
|---|---|---|
| The high-staining control is blank. | The cause is unresolved; retrieval, primary-antibody exposure or detection can fail in a paraffin IHC workflow (standard IHC practice). | Verify tissue and section quality, then check each workflow step and the same-run controls before interpreting test sections (standard IHC practice; HPA: hepatocytes and cells of Bowman’s capsule, High). |
| Color appears mainly in nuclei or along membranes. | That distribution conflicts with the expected cytosolic pattern (UniProt P00966: location and topology); morphology or nonspecific detection may be misleading (standard IHC practice). | Recheck compartment boundaries with the counterstain and compare a known high-staining cell population and detection controls (standard IHC practice; HPA: liver and kidney, High). |
| A reported Not detected cell population stains strongly. | Cross-reactivity or endogenous detection activity is possible, but HPA’s cell-specific observation alone cannot identify the cause (HPA: bone marrow or lymph node, Not detected). | Check a no-primary detection control and compare staining with a high-staining cell population on a controlled run (standard IHC practice; HPA: liver and kidney, High). |
| Diffuse color obscures the cells to be scored. | Blocking, washing or endogenous detection activity may contribute to background in chromogenic IHC (standard IHC practice). | Inspect a no-primary control, check blocking and washes, and score only identifiable cellular staining after background is resolved (standard IHC practice). |
| Staining intensity differs between sections. | HPA reports High, Medium, Low and Not detected findings across specified cell populations; differences in cell composition can affect the apparent section-wide result (HPA: tissue IHC). | Compare the same named cell type and a same-run high-staining control, then record intensity and background separately (standard IHC practice; HPA: liver and kidney, High). |
| Q: Should an IF/ICC nuclear signal be called expected ASS1 staining? | HPA supports cytosol as the main ICC-IF location and lists nucleoplasm only as an uncertain additional location (HPA: subcellular). | A: Prioritize cytosolic signal; treat nucleoplasmic signal as uncertain and assess it with appropriate IF controls (HPA: subcellular; standard IF practice). |
Experiment evidence
IHC & IF images showing ASS1 staining
M02212-1 · IHCIHC analysis of ASS1 using anti-ASS1 antibody (M02212-1). ASS1 was detected in paraffin-embedded section of human prostate cancer tissue. He
M02212-1 · IHCIHC analysis of ASS1 using anti-ASS1 antibody (M02212-1). ASS1 was detected in paraffin-embedded section of human breast cancer tissue. Heat
M02212-1 · IFIF analysis of ASS1 using anti-ASS1 antibody (M02212-1). ASS1 was detected in immunocytochemical section of MCF-7 cells. Enzyme antigen retr
M02212-2 · IHCIHC analysis of ASS1 using anti-ASS1 antibody (M02212-2). ASS1 was detected in paraffin-embedded section of human breast cancer tissue. Heat
M02212-2 · IHCIHC analysis of ASS1 using anti-ASS1 antibody (M02212-2). ASS1 was detected in paraffin-embedded section of human liver cancer tissue. Heat
M02212-2 · IFIF analysis of ASS1 using anti-ASS1 antibody (M02212-2). ASS1 was detected in immunocytochemical section of MCF-7 cells. Enzyme antigen retr
A02212-1 · IHCIHC analysis of ASS1 using anti-ASS1 antibody (A02212-1). ASS1 was detected in paraffin-embedded section of human Pancreatic Cancer tissue.
A02212-1 · IFIF analysis of ASS1 using anti-ASS1 antibody (A02212-1). ASS1 was detected in immunocytochemical section of HEPG2 cells. Enzyme antigen retr
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000130707-ASS1/tissue/cerebral+cortex#imid_5627076
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000130707-ASS1/tissue/colon#imid_5626442
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000130707-ASS1/tissue/liver#imid_5627003
HPA · KidneyHuman Protein Atlas IHC, Kidney. Source: https://www.proteinatlas.org/ENSG00000130707-ASS1/tissue/kidney#imid_5627012
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA020934; green = ASS1, blue = nucleus, red = microtubules.
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA020934; green = ASS1, blue = nucleus, red = microtubules.
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for ASS1 IHC & IF
🧪Run liver first: hepatocytes must show ASS1 staining (HPA: High in hepatocytes; UniProt P00966: expressed in adult liver). Use cerebellum as a negative comparator, focusing on the granular layer (HPA: Not detected in cells in the granular layer); on the liver slide, non-hepatocyte cells should show background-level chromogen, but their ASS1-negative status is unverified by the supplied evidence.
Positive control tissue: Kidney (Bowman's capsule, HPA High)
Negative control tissue: Bone marrow (HPA Not detected)
ICC-IF cell lines (HPA subcellular resource): HPA ICC-IF images show ASS1 in A-431, MCF-7, U2OS, with annotated localisation: Cytosol (supported) (HPA subcellular).
Technical controls: Include a no-primary, secondary-only control and a mouse IgG isotype control matched to the primary antibody (selected-SKU caption: mouse anti-ASS1); use an ASS1 knockout specimen, if available, as a biological specificity control. Check endogenous peroxidase and biotin background in liver because the caption uses biotinylated secondary antibody, streptavidin–biotin detection and DAB (selected-SKU caption).
⚠️Feasibility: A target-specific fixation window and fixation effect are unreported, and the exact M02212-1 tissue-IHC caption does not state the fixative (selected-SKU caption). The caption demonstrates heat-mediated retrieval in EDTA at pH 8.0 on a paraffin section, but does not establish that retrieval is required for every specimen (selected-SKU caption); the supplied evidence does not establish whether frozen-section staining or IF is easier. In liver, endogenous peroxidase or biotin may add background to the caption’s DAB and streptavidin–biotin detection, so interpret staining against the technical controls (selected-SKU caption).
HPA tissue IHC evidence for ASS1
Comprehensive Human Protein Atlas IHC scoring per tissue (reliability: Enhanced — Medium consistency between antibody staining and RNA expression data.). Rows are taken directly from the HPA tissue chart — click any row's HPA link to view the source.
Positive expression · recommended positive controls
| Tissue | Cell type | Level | Evidence | Source |
|---|---|---|---|---|
| Kidney | Bowman's capsule | High | Protein (IHC) | HPA → |
| Liver | Hepatocytes | High | Protein (IHC) | HPA → |
| Lung | Alveolar cells type II | High | Protein (IHC) | HPA → |
| Skin | Cells in basal layer | High | Protein (IHC) | HPA → |
| Urinary bladder | Urothelial cells | High | Protein (IHC) | HPA → |
Undetected expression · recommended negative controls
| Tissue | Cell type | Level | Evidence | Source |
|---|---|---|---|---|
| Bone marrow | Hematopoietic cells | Not detected | Protein (IHC) | HPA → |
| Cerebellum | Cells in granular layer | Not detected | Protein (IHC) | HPA → |
| Duodenum | Glandular cells | Not detected | Protein (IHC) | HPA → |
| Endometrium | Cells in endometrial stroma | Not detected | Protein (IHC) | HPA → |
| Epididymis | Glandular cells | Not detected | Protein (IHC) | HPA → |
Section 3
Advanced ASS1 IHC Tips
Troubleshoot ASS1 staining in paraffin sections using the catalog antibody’s tissue IHC example, with one entry on adapting the assay to IF.
Which retrieval conditions should I start with for weak ASS1 staining?
Start with heat-mediated retrieval in EDTA at pH 8.0 for paraffin sections (datasheet M02212-1). If signal is weak, check that sections were fully deparaffinised and that heating and cooling were consistent across the run (standard IHC practice). Run a liver section alongside the test tissue; hepatocytes show high ASS1 staining (HPA tissue IHC). Compare retrieved sections with a no-primary control before increasing antibody concentration, since background can mimic weak cytoplasmic signal (standard IHC practice; UniProt P00966 localisation). Record retrieval temperature and duration for each run so a change in staining can be traced to the processing step (standard IHC practice).
How should I investigate loss of ASS1 staining after fixation?
Target-specific ASS1 sensitivity to fixation is unknown from the supplied evidence; the paraffin-section caption does not state its fixative (caption M02212-1). Document the fixative and fixation duration for each block, then compare sections processed with matched retrieval and detection conditions (standard IHC practice). Include liver as a positive tissue reference because adult liver expression is reported and hepatocyte staining is high (UniProt P00966 tissue specificity; HPA tissue IHC). If the reference stains but a test block does not, review that block’s processing history before interpreting absence of signal (standard IHC practice). Do not assign the loss to a particular fixation mechanism without a controlled comparison (standard IHC practice).
What staining pattern is credible for ASS1 in paraffin sections?
Expect predominantly cytoplasmic staining: ASS1 is cytosolic and has no transmembrane segment (UniProt P00966 localisation and topology). HPA also reports cytoplasmic expression across several tissues, with high staining in liver hepatocytes and kidney Bowman’s capsule (HPA tissue IHC). Score nuclear staining separately instead of counting it automatically as positive, because HPA’s additional nucleoplasmic localisation is marked uncertain (HPA subcellular). Check cellular boundaries against the counterstain before assigning diffuse pigment to a particular cell population (standard IHC practice). If staining is exclusively membranous or nuclear, compare it with a positive tissue section and no-primary control before accepting it as ASS1 (UniProt P00966 localisation; standard IHC practice).
Could epitope choice explain discordant ASS1 staining between antibodies?
The supplied record lists 0 isoforms and a single ASS1 chain spanning residues 1–412 (UniProt P00966 processing and isoforms). It does not provide the catalog antibody’s epitope, so a difference between antibodies cannot be assigned to a specific sequence or modification (supplied record; datasheet M02212-1). ASS1 has annotated phosphorylation and acetylation sites, including Tyr87 and Lys112, but their effects on this antibody’s IHC staining are unknown (UniProt P00966 modified residues). Compare antibodies on adjacent sections with identical retrieval, detection, and counterstaining before interpreting discordance (standard IHC practice). Record each antibody’s stated immunogen or epitope if available, and keep compartment-specific scores separate (standard IHC practice; UniProt P00966 localisation).
How can I adapt the ASS1 tissue assay for multiplex IF?
Treat IF as a separate optimisation: the supplied catalog example demonstrates chromogenic IHC in a paraffin section, with no IF conditions stated (caption M02212-1). Pair ASS1 with a validated marker for the expected cell population, such as hepatocytes in liver, and assess each channel alone before multiplexing (HPA tissue IHC; standard IF practice). Choose fluorophores and filter sets after checking unstained tissue for autofluorescence, and include single-label controls for spectral bleed-through (standard IF practice). ASS1 is cytosolic with no transmembrane segment, so use permeabilisation appropriate for access to an intracellular epitope and titrate it against morphology (UniProt P00966 localisation and topology; standard IF practice). Keep fixation and antibody dilution specific to the IF optimisation rather than importing unreported conditions from the IHC caption (caption M02212-1; standard IF practice).
How do I reduce diffuse or granular background in ASS1 IHC?
First compare the stained section with no-primary and isotype-appropriate controls to separate detection-system background from antibody-dependent staining (standard IHC practice). The catalog example used 10% goat serum blocking, 2 μg/ml primary antibody overnight at 4°C, and a biotinylated secondary with DAB development (caption M02212-1). Check endogenous peroxidase blocking and, with a biotin-based system, assess endogenous biotin as possible sources of pigment (standard IHC practice). Titrate primary concentration and DAB development while retaining a liver positive control and matched exposure between sections (HPA tissue IHC; standard IHC practice). Interpret fine cytoplasmic signal in the expected cells separately from precipitate, tissue folds, and edge staining (UniProt P00966 localisation; standard IHC practice).
How should I score ASS1 across heterogeneous tissue regions? ⚠ ANSWER MARKED FOR VERIFICATION
Define the cell population and viable region before scoring, since ASS1 expression varies among tissues and cell types (HPA tissue IHC). For cellular staining, report the percentage of positive cells and an H-score based on cytoplasmic intensity; state the intensity categories and threshold used (UniProt P00966 localisation; standard IHC practice). If counting discrete positive cells, report density per mm² of analysed viable tissue and the number of sampled fields (standard IHC practice). Normalise comparisons to the same cell population, section area, staining batch, and image settings, with a shared positive control (standard IHC practice). Exclude folds, necrosis, and section edges using rules set before reviewing group identities (standard IHC practice).
When should apparent ASS1 positivity be treated as artefact?
A credible result has cytoplasmic signal in identifiable cells and agrees with a positive reference section; ASS1 is cytosolic (UniProt P00966 localisation; standard IHC practice). Liver hepatocytes and kidney Bowman’s capsule have reported high staining, whereas bone-marrow hematopoietic cells are reported as not detected (HPA tissue IHC). Isolated membrane staining, strong staining confined to section edges or necrotic areas, and pigment in a no-primary control warrant investigation (UniProt P00966 topology; standard IHC practice). Check endogenous peroxidase and biotin contributions when using the caption’s biotin-based DAB detection workflow (caption M02212-1; standard IHC practice). Treat an unexpected nuclear pattern cautiously because HPA marks nucleoplasmic localisation uncertain, and resolve it with controls or an independent antibody (HPA subcellular; standard IHC practice).
Boster reagents
Best ASS1 / Argininosuccinate synthase IHC Antibodies
Anti-ASS1 antibodies have IHC images from human paraffin sections and rat liver, plus IF images from HEPG2 and MCF-7 cells (catalog image captions); listed reactivity includes human, mouse, rat and monkey (catalog reactivity).
Real IHC data
Anti-ASS1 Antibody ® (monoclonal, 5I5)
Cat # M02212-1
Real IHC data
Anti-ASS1 Antibody ® (monoclonal, 7I9)
Cat # M02212-2
Real IHC data
Anti-ASS1 ® Antibody
Cat # A02212-1
M02212-1 shows human prostate cancer paraffin sections (M02212-1 IHC caption), and M02212-2 shows human breast cancer paraffin sections (M02212-2 IHC caption). A02212-1 shows human pancreatic cancer paraffin sections (A02212-1 IHC caption).
Which to pick: For tissue IHC, consider M02212-1: its captions show human prostate, breast and colon cancer paraffin sections and rat liver (M02212-1 IHC captions); the fixative is unreported in all three rendered IHC captions (M02212-1, M02212-2 and A02212-1 IHC captions). For IF/ICC, A02212-1 lists both applications and has an IF image in HEPG2 cells (A02212-1 applications and IF caption). For the broadest listed species coverage, M02212-1 (mouse monoclonal 5I5) and M02212-2 (mouse monoclonal 7I9) each list human, mouse, rat and monkey reactivity (catalog host, clone and reactivity); their IHC captions document human paraffin sections, and M02212-1 also documents rat liver (M02212-1 and M02212-2 IHC captions).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry P00966 (ASSY_HUMAN, Argininosuccinate synthase).
- Human Protein Atlas. ASS1 tissue IHC expression (reliability: Enhanced).
- Human Protein Atlas. ASS1 subcellular location (ICC-IF): Mainly localized to the cytosol. In addition localized to the nucleoplasm..
- Human Protein Atlas. ASS1 antibody validation summary (2 antibodies).
- A Phase 1 study of ADI-PEG20 (pegargiminase) combined with cisplatin and pemetrexed in ASS1-negative metastatic uveal melanoma. Pigment cell & melanoma research 2022 — PMC9322321.
- Loss of Argininosuccinate Synthetase-1 (ASS1) Occurs in Esophageal Adenocarcinoma and Represents a Promising Biomarker for Therapy with Pegargiminase. Cancers 2025 — PMC12650347.
- Reduced expression of argininosuccinate synthetase 1 has a negative prognostic impact in patients with pancreatic ductal adenocarcinoma. PloS one 2017 — PMC5302782.
- Differential expression of argininosuccinate synthetase in serous and non-serous ovarian carcinomas. The journal of pathology. Clinical research 2015 — PMC4858122.
- PubMed PMID:6194510 — UniProt-cited evidence.
- PubMed PMID:6321498 — UniProt-cited evidence.
- PubMed PMID:11941481 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for ASS1 (Argininosuccinate synthase). Expected localisation Cytoplasmic tissue staining (HPA tissue IHC); cytosolic protein (UniProt). Antigen retrieval: EDTA pH 8.0 HIER, heat-mediated (datasheet M02212-1). Validated IHC antibody: M02212-1 at 2μg/ml (the product's own IHC validation image is shown). Controls (HPA): positive Kidney (Bowman's capsule); negative Bone marrow. IHC-P workflow on paraffin sections; fixative unspecified. Protocol steps: 1. Sample: Paraffin-embedded human prostate cancer tissue; fixative not specified (datasheet M02212-1); 2. Fixation: Image fixative and duration unreported (datasheet M02212-1); 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: EDTA pH 8.0 (datasheet M02212-1); 20 min, 95–100 °C (standard); 6. Peroxidase block: 3% H2O2, 10 min , room temperature (standard); 7. Blocking: 10% goat serum (datasheet M02212-1); 8. Primary antibody: Mouse monoclonal (clone 5I5) anti-ASS1, 2μg/ml (datasheet M02212-1); 9. Primary incubation: Overnight at 4 °C (datasheet M02212-1). Watch for: Fixation: Keep fixation consistent across sections. (standard IHC practice; not target-specific); Caveat: Staining and RNA show medium consistency (HPA tissue IHC); Isoform / epitope: No annotated isoforms; one 1–412 chain (UniProt); Regulation: Expression regulation not reported (UniProt). Evidence: UniProt P00966, HPA tissue IHC · Enhanced, HPA ICC-IF · Mainly localized to the cytosol. In addition localized to the…, Datasheet M02212-1, PMC12650347, PMC5302782. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/ASS1/immunohistochemistry-ihc-guide.