KEGG: dre:100093704
UniGene: Dr.105281
SMIM7 (Small Integral Membrane Protein 7), also known as C19orf42 or hypothetical protein LOC79086, is a protein-coding gene located on chromosome 19p13.11 . The protein contains specific epitopes that have been successfully targeted for antibody production, particularly the amino acid sequence KKDTQGFGEESREPSTGDNIREFLLSLR, which has been used as an immunogen for generating polyclonal antibodies .
When designing experiments targeting SMIM7, researchers should note that:
The protein shows high sequence identity across species (96% with mouse, 100% with rat)
Subcellular localization studies indicate potential Golgi apparatus localization
Expression has been detected in human colon tissue with both cytoplasmic and nuclear positivity in glandular cells
This information is crucial for appropriate experimental design and interpretation of staining patterns when using SMIM7 antibodies.
SMIM7 antibodies have been validated for several research applications with specific optimal working conditions:
| Application | Recommended Dilution/Concentration | Critical Considerations |
|---|---|---|
| Immunohistochemistry (IHC) | 1:50 - 1:200 | HIER pH 6 retrieval recommended for paraffin sections |
| Immunocytochemistry (ICC) | 0.25-2 μg/ml or 1-4 μg/ml (varies by manufacturer) | PFA fixation and Triton X-100 permeabilization optimal |
| Immunofluorescence (IF) | 0.25-2 μg/ml | Same fixation and permeabilization as ICC |
| IHC-Paraffin | 1:50 - 1:200 | HIER pH 6 retrieval protocol critically important |
The most widely validated SMIM7 antibodies include rabbit polyclonal antibodies from Atlas Antibodies (HPA043127), Invitrogen (PA5-60250), and Novus Biologicals (NBP1-93497) . Validation data demonstrates that these antibodies recognize SMIM7 in human samples with specific subcellular patterns.
For reproducible results, researchers should carefully follow the recommended buffer systems (typically PBS pH 7.2 with 40% glycerol and 0.02% sodium azide) and storage conditions (4°C short-term; -20°C long-term with aliquoting to avoid freeze-thaw cycles) .
Validating antibody specificity is essential for reliable experimental outcomes. For SMIM7 antibodies, multiple complementary approaches should be employed:
Protein array validation: Confirm antibody specificity against SMIM7 in the presence of other non-target proteins. Commercial antibodies often undergo validation on protein arrays containing the target plus hundreds of non-specific proteins .
Immunoblotting controls:
Orthogonal validation: Compare staining patterns from antibodies raised against different epitopes of SMIM7 or from different host species.
Cross-species reactivity assessment: Test antibody against samples from different species based on sequence homology (mouse - 96%, rat - 100%) to confirm predicted cross-reactivity.
Subcellular localization consistency: Confirm that observed localization patterns (e.g., Golgi apparatus) are consistent across multiple experimental systems and with bioinformatic predictions.
Detecting low-abundance proteins like SMIM7 in complex neuronal tissues requires specialized methodological approaches:
Signal amplification systems:
Implement tyramide signal amplification (TSA) to enhance chromogenic or fluorescent signals while maintaining specificity
Utilize biotin-streptavidin amplification with careful blocking of endogenous biotin
Consider quantum dot-conjugated secondary antibodies for improved signal-to-noise ratio and photostability
Sample preparation optimization:
Extended fixation periods may mask epitopes; optimize fixation time (typically 12-24 hours) for neural tissues
For SMIM7 detection in brain samples, test multiple antigen retrieval methods beyond standard HIER pH 6
Consider using thick sections (40-100 μm) with extended antibody incubation times for better signal detection
Advanced microscopy techniques:
Quantitative analysis:
These approaches have been successfully implemented in studies examining protein expression in cerebellum, frontal and cingulate gyrus cortex, and hippocampus of normal and neurological disease-affected human brain tissues .
Epitope masking can significantly impact the detection of SMIM7, particularly when studying protein interactions:
Pre-analytical considerations:
Implement a systematic approach testing multiple fixatives (PFA, methanol, acetone) as protein interactions may differentially affect epitope accessibility
Test protease-induced epitope retrieval (PIER) alongside heat-induced epitope retrieval (HIER) methods
Consider native-state preservation techniques for interaction studies
Advanced epitope retrieval protocols:
Implement sequential antigen retrieval using both heat and enzymatic methods
Test pH gradient series (pH 3-10) to identify optimal conditions for SMIM7 epitope exposure
Consider using protein denaturants at controlled concentrations to expose hidden epitopes
Proximity labeling approaches:
Implement BioID or APEX2 proximity labeling to identify SMIM7 interaction partners without relying on antibody accessibility
Use chemical crosslinking followed by mass spectrometry (XL-MS) to detect transient interactions
Computational prediction:
Analyze potential protein-protein interaction interfaces using structural prediction tools
Identify regions of SMIM7 likely to be exposed or masked based on predicted secondary structure
Alternative detection strategies:
Consider epitope tagging of SMIM7 (if expression systems are available) for detection via tag-specific antibodies
Use protein array technologies to screen for interactions in controlled environments
These approaches address the complex challenges of studying membrane protein interactions where conformational changes and binding partners can significantly affect antibody accessibility.
Multiplex immunostaining with SMIM7 antibodies requires careful methodological planning:
Antibody panel design:
Select antibodies from different host species to avoid cross-reactivity
When using multiple rabbit polyclonal antibodies (common for SMIM7), implement sequential staining with thorough blocking and stripping steps
Validate each antibody individually before combining into multiplex panels
Signal separation strategies:
For fluorescence multiplex: Select fluorophores with minimal spectral overlap
For chromogenic multiplex: Use spectrally distinct chromogens with different cellular compartments (nuclear vs. cytoplasmic)
Consider tyramide-based signal amplification with sequential covalent labeling
Protocol optimization:
Determine the optimal order of antibody application (typically start with lowest abundance target)
For SMIM7 detection in multiplex panels, optimal antigen retrieval conditions (HIER pH 6) should be compatible with other targets
Implement microwave treatment between rounds to effectively eliminate previous primary antibodies
Validation controls for multiplex specificity:
Single-stain controls on serial sections to confirm staining patterns
Absorption controls using immunizing peptides for SMIM7 and other targets
Fluorescence minus one (FMO) controls to assess bleed-through
Advanced image analysis:
Implement spectral unmixing algorithms for fluorescence multiplex
Use computational approaches to separate overlapping signals
Apply machine learning for automated cell classification and quantification
These methodological considerations ensure reliable data generation in complex multiplex experiments incorporating SMIM7 detection.
Inconsistent staining is a common challenge with SMIM7 antibodies. Systematic troubleshooting should include:
Antibody validation and handling:
Verify antibody lot consistency through standardized positive controls
Implement proper antibody storage: aliquot upon receipt to avoid freeze-thaw cycles
Standardize antibody concentration using quantitative methods rather than relying solely on dilution ratios
Sample preparation standardization:
Implement consistent fixation protocols with controlled temperature and duration
Standardize tissue processing, especially time in fixative and dehydration steps
For FFPE tissues, monitor storage time as antigenicity can decrease over extended storage periods
Protocol calibration:
Establish titration curves for each new antibody lot
Implement automated staining platforms where possible to reduce manual variation
Develop and use detailed standard operating procedures (SOPs) with specific timing parameters
Quality control measures:
Include standardized positive and negative control tissues in each experiment
Consider using tissue microarrays for batch calibration
Implement quantitative image analysis to detect subtle variations in staining intensity
Systematic record-keeping:
Document all experimental variables including reagent lot numbers, incubation times, and temperature fluctuations
Maintain detailed antibody validation records including specificity testing data
Create a laboratory database of staining results with standardized evaluation criteria
These methodological approaches have been derived from practices used in multi-site validation studies of research antibodies and can significantly improve reproducibility.
Distinguishing specific from non-specific binding requires rigorous methodological controls:
Comprehensive control system:
Advanced validation techniques:
Implement orthogonal detection methods (e.g., in situ hybridization for SMIM7 mRNA)
Compare staining patterns across multiple antibodies targeting different SMIM7 epitopes
Validate with genetic approaches (siRNA knockdown, CRISPR knockout) where possible
Signal-to-noise optimization:
Systematically optimize blocking conditions (test BSA, normal serum, commercial blockers)
Implement stringent washing protocols with detergent optimization
Test antibody diluents containing competing proteins or mild detergents
Analytical approaches:
Implement quantitative image analysis to establish signal-to-background thresholds
Use spectral imaging to distinguish true signal from autofluorescence
Apply computational analysis to establish staining pattern consistency
Publication standards:
Report detailed antibody validation including all negative results
Document antibody catalog numbers, lot numbers, and RRID identifiers
Share raw image data to enable independent evaluation
These approaches align with enhanced validation standards recommended for antibody-based research and significantly improve data reliability.
Optimizing fixation and antigen retrieval requires systematic method development:
Fixation optimization:
Test multiple fixation methods: 10% neutral buffered formalin, 4% paraformaldehyde, Bouin's solution, alcohol-based fixatives
Evaluate fixation times (4, 12, 24, 48 hours) to determine optimal epitope preservation
For delicate tissues, consider using PAXgene or other molecular-friendly fixatives
Antigen retrieval matrix testing:
Create a systematic matrix testing different retrieval conditions:
pH series: pH 6 citrate, pH 9 Tris-EDTA, pH 3 glycine
Heating methods: microwave, pressure cooker, water bath
Duration series: 10, 20, 30 minutes
Enzymatic methods: proteinase K, trypsin, pepsin
Tissue-specific protocol adaptation:
Develop tissue-specific protocols as epitope accessibility varies across tissues:
Neural tissues: may require extended retrieval times
Fibrous tissues: often benefit from dual retrieval approaches
Adipose tissues: require optimization of deparaffinization and retrieval
Retrieval buffer additives:
Test retrieval enhancers:
Calcium chelators (EDTA)
Detergents (0.05% Tween-20)
Reducing agents (2-mercaptoethanol) for disulfide-rich samples
Validation across tissue types:
Create a standardized panel of different tissues for protocol validation
Document tissue-specific variations in optimal protocols
Develop and maintain a laboratory database of optimal conditions by tissue type
This systematic approach has been demonstrated to significantly improve detection sensitivity while maintaining specificity in antibody-based research protocols.
SMIM7 antibodies can provide valuable insights in neurological disease research through several methodological approaches:
Expression profiling in disease states:
Implement quantitative immunohistochemistry to assess SMIM7 expression changes across different neurological disorders
Studies have shown differential dysregulation of various proteins in cerebellum, frontal and cingulate gyrus cortex, and hippocampus of brain affected by Parkinson's disease, Lewy Body Dementia, and cognitive defects
Use digital pathology approaches with machine learning for unbiased quantification
Subcellular localization analysis:
Employ high-resolution confocal microscopy to track potential changes in SMIM7 localization in disease models
Implement immunogold electron microscopy for ultrastructural localization
Combine with markers of cellular stress or protein aggregation to identify potential associations
Protein interaction studies:
Use SMIM7 antibodies in co-immunoprecipitation studies to identify interaction partners
Implement proximity ligation assays (PLA) to detect protein-protein interactions in situ
Compare interaction profiles between normal and disease-affected tissues
Functional studies:
Combine with activity-dependent markers to correlate SMIM7 expression with neuronal function
Implement time-course studies following experimental manipulations in disease models
Use in combination with electrophysiological recordings to correlate protein expression with functional outcomes
Biomarker development:
Evaluate SMIM7 as a potential biomarker by correlating expression with disease progression
Implement multiplexed approaches combining SMIM7 with established disease markers
Develop quantitative assays for potential diagnostic applications
These applications demonstrate how SMIM7 antibodies can be integrated into comprehensive research programs investigating the molecular basis of neurological disorders.
Improving reproducibility in quantitative SMIM7 expression analysis requires:
Standardized sample preparation:
Implement consistent protocols for tissue collection, fixation, and processing
Use automated systems where possible to reduce operator variability
Establish timing controls for all critical steps (fixation, antigen retrieval, antibody incubation)
Calibrated detection systems:
Incorporate calibration standards in immunohistochemistry/immunofluorescence protocols
Use reference samples with known SMIM7 expression levels in each batch
Implement internal controls for normalization (housekeeping proteins, total protein stains)
Quantification methodology:
Develop standard operating procedures for image acquisition:
Standardized exposure settings
Consistent thresholding approaches
Field selection criteria to avoid bias
Statistical considerations:
Implement power calculations to determine appropriate sample sizes
Use statistical methods that account for nested data structures (multiple measurements per sample)
Report all data normalization steps and statistical approaches in detail
Advanced image analysis workflows:
These methodological approaches align with recent efforts to improve reproducibility in antibody-based research and can significantly enhance data quality and reliability.
Interpreting subcellular localization of SMIM7 requires systematic analysis and integration with functional data:
Multi-scale imaging approach:
Combine widefield, confocal, and super-resolution microscopy for comprehensive localization analysis
Implement electron microscopy for definitive organelle localization
Use live-cell imaging with tagged constructs to confirm antibody-based observations
Co-localization studies:
Functional correlation:
Correlate localization patterns with cell states (proliferation, differentiation, stress)
Track potential translocation following experimental manipulations
Implement temporal studies to identify dynamic localization changes
Computational analysis:
Apply quantitative co-localization metrics (Pearson's coefficient, Mander's overlap)
Use algorithms that correct for random overlap and diffraction limitations
Implement 3D reconstruction to fully capture spatial relationships
Integration with structural predictions:
Compare observed localization with bioinformatic predictions of targeting signals
Analyze protein domain structure in relation to observed localization patterns
Consider post-translational modifications that might affect localization
This multifaceted approach provides a robust framework for interpreting subcellular localization data and generating hypotheses about SMIM7 function.
Generating anti-idiotype antibodies against SMIM7 antibodies involves specialized methodological considerations:
Anti-idiotype antibody development strategies:
Phage display approach: Generate phage-displayed scFv libraries using RNA from animals immunized with the idiotype SMIM7 antibody, similar to methods used for anti-CD22 antibodies
Hybridoma technology: Immunize mice with purified SMIM7 antibodies and screen hybridomas for those producing antibodies that specifically recognize the variable regions of the original antibody
Recombinant approaches: Use computational design based on crystal structures of antibody-antigen complexes to engineer anti-idiotype antibodies with customized specificity profiles
Validation of anti-idiotype antibodies:
Binding specificity assessment: Test against the original SMIM7 antibody, isotype-matched control antibodies, and unrelated antibodies using ELISA and surface plasmon resonance
Epitope mapping: Determine if the anti-idiotype recognizes the paratope (binding site) of the SMIM7 antibody
Competition assays: Confirm the anti-idiotype antibody inhibits binding of the original antibody to SMIM7 protein
Classification and applications:
Troubleshooting considerations:
Address potential cross-reactivity with structurally similar antibodies
Develop strategies for preserving binding activity during labeling procedures
Implement quality control measures for batch-to-batch consistency
These approaches can provide valuable research tools for tracking SMIM7 antibodies in complex biological systems and developing novel assay platforms.
Enhanced validation requires comprehensive methodological approaches aligned with current reproducibility standards:
Orthogonal validation:
Correlate antibody-based detection with orthogonal methods (mass spectrometry, RNA-seq)
Implement in situ hybridization to correlate protein detection with mRNA expression
Compare results across multiple antibodies targeting different SMIM7 epitopes
Genetic strategy validation:
Use CRISPR/Cas9-mediated knockout models to confirm antibody specificity
Implement siRNA knockdown with quantitative assessment of signal reduction
Test in overexpression systems with controlled expression levels
Independent method verification:
Validate key findings using independent detection methods
Implement cell fractionation with Western blotting to confirm subcellular localization
Use recombinant expression systems with epitope tags for verification
Cross-laboratory validation:
Establish collaborative validation across multiple research sites
Implement standardized protocols with detailed documentation
Use identical sample sets with blinded analysis
Transparent reporting:
Document complete validation data including negative results
Report Research Resource Identifiers (RRIDs) for all antibodies
Share original images and quantification methods
These enhanced validation approaches align with recent guidelines from scientific societies and funding agencies aimed at improving reproducibility in antibody-based research.
Studying post-translational modifications (PTMs) of SMIM7 requires specialized methodological considerations:
Modification-specific antibody selection:
Evaluate commercial availability of PTM-specific antibodies (phospho-, glyco-, ubiquitin-specific)
Consider custom antibody development against predicted modification sites
Implement rigorous validation for PTM-specific antibodies, including competition with modified and unmodified peptides
Sample preparation optimization:
Preserve labile modifications through rapid sample processing
Implement phosphatase inhibitors, deubiquitinase inhibitors, or other PTM-preserving protocols
Consider specialized fixation methods that preserve specific modifications
Enrichment strategies:
Use immunoprecipitation with SMIM7 antibodies followed by PTM-specific detection
Implement PTM enrichment methods (phosphopeptide enrichment, lectin affinity, etc.)
Consider proximity ligation assays to detect modified forms in situ
Confirmation approaches:
Validate antibody-based findings with mass spectrometry
Use site-directed mutagenesis of potential modification sites
Implement in vitro modification systems with purified enzymes
Functional correlation:
Correlate PTM detection with functional assays
Track modifications under different cellular conditions
Implement temporal studies to track dynamic modification patterns
These methodological considerations provide a framework for reliable investigation of SMIM7 post-translational modifications using antibody-based approaches.
Emerging technologies offer exciting possibilities for next-generation SMIM7 antibodies:
Recombinant antibody platforms:
Nanobody and alternative scaffold development:
Generate camelid nanobodies against SMIM7 for improved penetration into tissue sections
Explore alternative binding scaffolds (affibodies, DARPins) for novel epitope recognition
Develop smaller binding agents for improved tissue penetration and reduced background
Affinity maturation and specificity engineering:
Advanced conjugation strategies:
Develop site-specific conjugation methods for controlled reporter attachment
Implement branched detection systems for signal amplification
Create bispecific formats combining SMIM7 recognition with contextual markers
Enhanced reporting systems:
Develop proximity-dependent activation for improved signal-to-noise ratio
Implement split reporter systems for detecting protein interactions
Create environmentally-responsive antibody conjugates for functional detection
These approaches highlight how emerging antibody engineering technologies can be applied to develop improved SMIM7 detection tools with enhanced performance characteristics.
Investigating SMIM7 interaction networks requires integrated methodological approaches:
Comprehensive interaction screening:
Implement antibody-based co-immunoprecipitation followed by mass spectrometry
Apply BioID or APEX2 proximity labeling to identify neighboring proteins
Develop SMIM7-based yeast two-hybrid or mammalian two-hybrid screens
Validation of interaction candidates:
Confirm interactions through reciprocal co-immunoprecipitation
Implement proximity ligation assays for in situ detection of protein interactions
Use FRET or BRET approaches for live-cell interaction analysis
Contextual interaction mapping:
Map interactions across different cellular conditions (stress, differentiation, etc.)
Implement temporal studies to identify dynamic interaction patterns
Develop tissue-specific interaction maps using spatial proteomics
Functional analysis of interactions:
Apply targeted disruption of specific interactions through mutagenesis
Develop competing peptides based on interaction interfaces
Implement inducible protein degradation systems to study functional consequences
Computational integration:
Apply network analysis to position SMIM7 within larger interactome networks
Implement machine learning approaches to predict functional modules
Develop visualization tools for complex interaction datasets