2.1. Gout and Uric Acid Metabolism
ALDH16A1 interacts with hypoxanthine-guanine phosphoribosyltransferase 1 (HPRT1), a key enzyme in purine salvage pathways. Mutations in ALDH16A1 impair this interaction, leading to hyperuricemia and gout . Antibodies have been used to confirm protein-protein interactions in studies linking ALDH16A1 variants (e.g., Pro527Arg) to disrupted HPRT1 activity .
2.2. Tumor Progression
In glioblastoma, ALDH16A1 expression correlates with tumor cell proliferation and migration. Antibody-based assays have shown that ALDH16A1 knockdown induces cell-cycle arrest and epithelial-mesenchymal transition (EMT) inhibition, suggesting its role as a therapeutic target .
2.3. Mast Syndrome
ALDH16A1 interacts with maspardin, a protein truncated in Mast syndrome (hereditary spastic paraplegia). Antibodies have localized ALDH16A1 to kidney and liver tissues, aiding in understanding its tissue-specific roles .
Western Blot: Antibodies detect a 85 kDa band in human cell lysates (e.g., HeLa, HepG2) .
IHC: Staining reveals expression in kidney proximal tubules and liver zone 3 hepatocytes .
ELISA: Used for quantifying ALDH16A1 in plasma or tissue lysates .
Kidney Function: ALDH16A1 knockout mice exhibit upregulated lipid metabolism genes and altered urate transporters (e.g., Abcc4, Slc16a9) .
Glioma Prognosis: ALDH16A1 expression levels correlate with tumor aggressiveness and immune infiltration .
Mast Syndrome: ALDH16A1 colocalizes with maspardin in neuronal tissues, suggesting a role in neurodegeneration .
When selecting antibodies for renal immunohistochemistry, prioritize clones validated for:
Epitope localization: Antibodies targeting the N-terminal (e.g., Aviva Systems Biology ARP67350_P050) show consistent reactivity in proximal/distal tubules .
Species cross-reactivity: Confirm reactivity with experimental models (e.g., BosterBio’s antibody validated for human/mouse/rat) .
Fixation compatibility: Pilot studies using paraffin-embedded vs. frozen sections are essential, as ALDH16A1’s conformational sensitivity varies by tissue processing .
Methodological recommendation:
Perform antigen retrieval using pH 9.0 Tris-EDTA buffer for 20 min at 95°C.
Include knockout tissue controls to confirm signal specificity .
Quantify staining intensity across cortical vs. medullary regions using automated image analysis platforms.
Validation requires a multi-platform approach:
Molecular weight verification: Compare observed bands (75 kDa canonical, 55 kDa isoform) against recombinant standards .
Knockout validation: Use tissues from Aldh16a1 −/− mice as negative controls .
Cross-reactivity testing: Validate against other ALDH isoforms (ALDH1A1, ALDH2, ALDH3A1) using overexpression lysates .
A tiered localization protocol is advised:
Subcellular fractionation: Confirm cytoplasmic vs. membrane association via differential centrifugation .
Multi-resolution microscopy: Combine widefield (10x) surveys with super-resolution (STED) imaging of tubular structures .
Co-localization metrics: Calculate Pearson coefficients for markers like aquaporin-1 (proximal tubules) or THP (distal tubules) .
Critical controls:
Isotype-matched IgG at matching concentrations
Contradictions often arise from:
Strain-specific compensation: C57BL/6N vs. BALB/c backgrounds show differential Abcc4 upregulation .
Temporal effects: Collect data at multiple timepoints (e.g., 8/16/24 weeks post-knockout).
Analytical framework:
Normalize counts using TMM-weighted log2(CPM).
Conduct pathway overrepresentation analysis (ORA) with STRING-DB v12.0.
Validate top hits (e.g., Slc16a9, Abcc4) via Nanostring nCounter .
| Parameter | KO Model Value | WT Control Value |
|---|---|---|
| Average read depth | 45M ± 3.2M | 42M ± 2.8M |
| Differentially expressed genes (FDR <0.05) | 327 upregulated | 214 downregulated |
| Top enriched pathway | Lipid metabolic process (GO:0006629) | Xenobiotic transport (GO:0042908) |
Implement multimodal imaging pipelines:
Correlative light-electron microscopy (CLEM): Map antibody signals to ultrastructural features (e.g., ER membranes vs. cytoplasmic vesicles) .
Fluorescence lifetime imaging (FLIM): Detect protein-protein interactions via FRET efficiency changes between ALDH16A1 and HPRT1 .
Spatial transcriptomics: Combine Visium HD (10x Genomics) with IHC to link mRNA-protein expression gradients .
Case study: CLEM revealed ALDH16A1’s dual localization in S3 tubules – 68% cytoplasmic, 32% associated with mitochondrial outer membranes .
For missense variants (e.g., p.Pro527Arg):
Molecular dynamics simulations:
Docking analysis:
Solvation model: TIP3P explicit water
Force field: ff19SB for proteins
Cluster analysis with 2Å cutoff
Key design considerations:
Interaction screening: Employ BioID2 proximity labeling to map interactomes in renal cells .
Metabolomic integration: Pair LC-MS/MS data (e.g., uric acid, hypoxanthine) with co-immunoprecipitation results .
Allosteric mutagenesis: Introduce mutations distant from catalytic pseudo-sites (e.g., D458A) to test scaffolding roles .
Example workflow: