fam151a Antibody

What is FAM151A and why is it significant for research?

FAM151A (Family with sequence similarity 151 member A) is a transmembrane protein encoded by the FAM151A gene located on chromosome 1 at position 1p32.3. This protein has gained research significance due to its expression patterns in kidney tubules and its potential role in cellular signaling pathways . FAM151A is an ortholog of menorin, a protein involved in neuron development in nematodes, suggesting evolutionary conservation of important biological functions . The protein contains one transmembrane domain and two domains of unknown function (DUF2181), with DUF2181 belonging to the GDPD/PLCD superfamily known to hydrolyze glycerophosphodiester bonds . Research interest has increased following the discovery that an SNP in FAM151A (rs11206394) is a significant predictor of colorectal cancer, highlighting its potential clinical relevance .

What types of FAM151A antibodies are available for research?

Researchers can access several types of FAM151A antibodies optimized for different experimental applications. The primary categories include:

• Polyclonal antibodies: Such as rabbit-derived affinity-isolated antibodies that recognize human FAM151A protein sequences .

• Monoclonal antibodies: Including mouse monoclonal IgG1 kappa light chain antibodies (like G-10) that specifically detect human FAM151A protein .

• Conjugated antibodies: FAM151A antibodies are available with various conjugations including:

  • Horseradish peroxidase (HRP) for enhanced chemiluminescent detection

  • Fluorescent tags such as FITC, PE, and Alexa Fluor for immunofluorescence applications

  • Agarose conjugations for immunoprecipitation studies

These diverse antibody formats enable researchers to select the most appropriate tool for their specific experimental design and detection method requirements .

How is FAM151A expression distributed across tissues?

The expression pattern of FAM151A shows interesting tissue specificity that researchers should consider when designing experiments. According to current research:

• mRNA distribution: FAM151A transcripts have been detected in kidney, small intestine, and liver tissues, indicating transcriptional activity in these organs .

• Protein expression: Despite the wider mRNA distribution, the FAM151A protein expression appears to be restricted primarily to kidney tubules, suggesting post-transcriptional regulation mechanisms .

• Cellular localization: As a transmembrane protein, FAM151A localizes to cellular membranes, consistent with its structural features that include a transmembrane domain .

This distinct expression pattern provides important context for experimental design, particularly for tissue selection in immunohistochemistry studies and for interpreting functional data. The restricted protein expression despite broader mRNA presence suggests complex regulatory mechanisms that may themselves be worthy of investigation .

What criteria should researchers use when selecting a FAM151A antibody?

When selecting a FAM151A antibody for research applications, consider these critical factors:

• Target epitope: Determine which region of FAM151A your research requires targeting. For example, some antibodies target amino acids 454-500 of the human protein . Match the epitope to your research question, especially if you're studying specific domains like the DUF2181 regions.

• Species reactivity: Verify the antibody's species reactivity aligns with your experimental model. Currently available antibodies primarily target human FAM151A, though some may cross-react with orthologs from closely related species .

• Application compatibility: Different experimental techniques require antibodies validated for specific applications. For instance:

  • For immunohistochemistry: Consider antibodies validated at dilutions of 1:200-1:500

  • For western blot: Look for antibodies validated at 0.04-0.4 μg/mL concentrations

• Clonality considerations: Polyclonal antibodies like HPA016840 may offer broader epitope recognition, while monoclonal antibodies like G-10 provide high specificity for particular epitopes .

• Validation evidence: Review available validation data, particularly those with enhanced validation through recombinant expression systems .

Proper antibody selection directly impacts experimental outcomes, making this decision critical to research success.

How can researchers validate FAM151A antibody specificity?

Validating antibody specificity is critical for ensuring experimental integrity. For FAM151A antibodies, a comprehensive validation strategy should include:

• Knockout/knockdown controls:

  • Utilize CRISPR/Cas9 knockout systems specifically targeting the FAM151A gene

  • Compare antibody reactivity between wild-type and FAM151A-depleted samples

  • Absence of signal in knockout samples confirms specificity

• Overexpression studies:

  • Express tagged recombinant FAM151A in model systems

  • Confirm co-localization of antibody signal with tag-specific antibodies

  • Observe increased signal intensity proportional to expression level

• Peptide competition assays:

  • Pre-incubate the antibody with the immunogen peptide sequence

  • Apply the peptide-antibody mixture to samples

  • Specific binding should be blocked by the peptide, resulting in signal reduction

• Cross-reactivity assessment:

  • Test against FAM151B, the known paralog of FAM151A

  • Evaluate potential cross-reactivity with other GDPD/PLCD superfamily members

  • Confirm signal patterns match known tissue distribution (kidney tubules)

• Multiple antibody confirmation:

  • Use antibodies from different sources targeting distinct epitopes

  • Consistent results across different antibodies strengthen validation

Thorough validation creates confidence in subsequent experimental results and facilitates accurate interpretation of FAM151A biology .

What are the optimal storage and handling conditions for FAM151A antibodies?

Proper storage and handling of FAM151A antibodies is essential for maintaining their functionality and ensuring reproducible experimental results:

• Storage temperature:

  • Store unconjugated antibodies at -20°C for long-term preservation

  • Avoid repeated freeze-thaw cycles by preparing working aliquots

• Buffer composition considerations:

  • Most commercial FAM151A antibodies are supplied in buffered aqueous glycerol solutions that help maintain stability

  • The glycerol content prevents freezing at -20°C and preserves antibody structure

• Working dilution preparation:

  • For immunohistochemistry applications, prepare working dilutions (1:200-1:500) immediately before use

  • For western blotting, prepare fresh dilutions (0.04-0.4 μg/mL) in appropriate blocking buffer

• Shipping conditions:

  • FAM151A antibodies are typically shipped on wet ice and should be transferred to -20°C storage immediately upon receipt

• Stability monitoring:

  • Regularly test antibody performance with positive controls

  • Document lot-to-lot variations by maintaining reference samples

  • Consider including stability time points in validation studies

Adherence to these handling protocols helps ensure consistent antibody performance across experiments and extends the useful lifetime of these valuable reagents .

What are the optimal protocols for using FAM151A antibodies in western blotting?

For optimal western blotting results with FAM151A antibodies, follow this methodological approach:

• Sample preparation:

  • Prioritize kidney tissue extracts as FAM151A protein is predominantly expressed in kidney tubules

  • Use RIPA buffer with protease inhibitors for efficient protein extraction

  • Include positive controls (kidney extracts) and negative controls (tissues not expressing FAM151A)

• Gel electrophoresis considerations:

  • Use 8-10% polyacrylamide gels to properly resolve FAM151A (approximately 95 kDa)

  • Load 20-40 μg of total protein per lane for endogenous detection

  • Include molecular weight markers covering 70-120 kDa range

• Transfer and blocking:

  • Transfer proteins to PVDF membranes (preferred over nitrocellulose for this protein)

  • Block with 5% non-fat dry milk in TBST for 1 hour at room temperature

• Antibody incubation:

  • Dilute primary FAM151A antibodies to 0.04-0.4 μg/mL in blocking buffer

  • Incubate membranes overnight at 4°C with gentle agitation

  • Wash 4x with TBST, 5 minutes each

  • Incubate with appropriate HRP-conjugated secondary antibody (1:5000-1:10000) for 1 hour

• Detection optimization:

  • Use enhanced chemiluminescence detection systems

  • For low expression samples, consider signal enhancement systems or directly conjugated FAM151A-HRP antibodies

  • Expected band size is approximately 95 kDa, corresponding to full-length FAM151A protein

This protocol should yield specific detection of FAM151A protein while minimizing background and non-specific signals .

How should researchers optimize immunohistochemistry protocols for FAM151A detection?

For optimal immunohistochemical detection of FAM151A in tissue sections, implement the following protocol adaptations:

• Tissue preparation:

  • Use formalin-fixed, paraffin-embedded kidney tissue sections (4-6 μm thickness)

  • Include other tissues (small intestine, liver) for comparative expression analysis

  • Perform heat-induced epitope retrieval using citrate buffer (pH 6.0) for 20 minutes

• Blocking and permeabilization:

  • Block endogenous peroxidase activity with 3% H₂O₂ for 10 minutes

  • Permeabilize with 0.1% Triton X-100 if working with cell preparations

  • Block non-specific binding with 5% normal serum from the same species as the secondary antibody

• Antibody incubation:

  • Apply FAM151A primary antibody at 1:200-1:500 dilution

  • Incubate in a humidified chamber at 4°C overnight

  • For double-labeling studies, combine with tubular segment markers to precisely locate FAM151A expression

• Visualization strategy:

  • Use compatible detection systems based on your primary antibody species (rabbit or mouse)

  • For brightfield microscopy: HRP-conjugated secondary antibodies with DAB substrate

  • For fluorescence: Apply fluorophore-conjugated secondaries or directly use fluorophore-conjugated FAM151A antibodies

• Counterstaining and controls:

  • Counterstain nuclei with hematoxylin (brightfield) or DAPI (fluorescence)

  • Include positive controls (kidney sections) and negative controls (primary antibody omission)

  • Consider peptide competition controls to verify specificity

This protocol emphasizes the known tissue distribution of FAM151A while providing flexibility for different visualization requirements .

What considerations are important for immunoprecipitation experiments using FAM151A antibodies?

When performing immunoprecipitation (IP) of FAM151A, consider these critical methodological aspects:

• Antibody selection for IP:

  • Choose agarose-conjugated FAM151A antibodies for direct precipitation

  • Alternatively, use unconjugated antibodies with protein A/G beads

  • Monoclonal antibodies like G-10 are often preferred for IP due to their specificity

• Lysate preparation:

  • Use kidney-derived cell lines or tissue for optimal endogenous protein levels

  • Prepare lysates in non-denaturing buffers (e.g., NP-40 or CHAPS-based)

  • Clear lysates by centrifugation (14,000 × g, 10 min, 4°C) before antibody addition

• Pre-clearing strategy:

  • Pre-clear lysates with protein A/G beads alone to reduce non-specific binding

  • Reserve 5-10% of pre-cleared lysate as input control

  • Use 500-1000 μg of total protein per IP reaction

• Immunoprecipitation procedure:

  • For agarose-conjugated antibodies, use 20-40 μl of affinity matrix per IP

  • For unconjugated antibodies, use 2-5 μg antibody per 500 μg protein

  • Incubate overnight at 4°C with gentle rotation

  • Wash beads 4-5 times with cold IP buffer containing reduced detergent

• Elution and analysis:

  • Elute immunoprecipitated complexes with 2X SDS sample buffer

  • Analyze by western blotting using a different FAM151A antibody (different species or epitope)

  • Visualize interacting proteins by mass spectrometry for protein-protein interaction studies

This protocol maximizes the chances of successfully isolating FAM151A and its interacting partners for downstream analyses .

How can researchers troubleshoot weak or absent FAM151A signals in western blots?

When encountering weak or absent FAM151A signals in western blots, consider this systematic troubleshooting approach:

• Sample-related issues:

  • Verify sample source - FAM151A protein is predominantly expressed in kidney tubules and appears absent in many other tissues despite mRNA presence

  • Increase protein loading (40-60 μg per lane) for endogenous detection

  • Check protein integrity by Ponceau S staining of membrane

  • Use fresh tissue samples to avoid protein degradation

• Antibody performance factors:

  • Test different FAM151A antibody concentrations (range: 0.04-0.8 μg/mL)

  • Consider alternative FAM151A antibody clones if one fails to detect the protein

  • Include positive controls (commercial recombinant FAM151A protein)

  • Verify antibody activity with a known positive sample

• Technical modifications:

  • Extend primary antibody incubation time (overnight at 4°C)

  • Optimize transfer conditions for high molecular weight proteins (~95 kDa)

  • Try different membrane types (PVDF often superior to nitrocellulose for some antibodies)

  • Use enhanced sensitivity detection reagents

• Buffer and protocol adjustments:

  • Test alternative blocking agents (BSA instead of milk) if phosphorylated epitopes are targeted

  • Add 0.1% SDS to antibody dilution buffer to enhance accessibility

  • Modify wash stringency and duration

  • Consider native versus reducing conditions if epitope is conformation-sensitive

• Identification verification:

  • Confirm band identity using overexpression systems

  • Run FAM151A-depleted samples (CRISPR knockout) as specificity controls

  • Check for post-translational modifications that might alter migration pattern

This systematic approach helps identify and resolve technical issues preventing successful FAM151A detection .

What are common pitfalls in FAM151A immunohistochemistry and how can they be addressed?

Several common pitfalls can affect FAM151A immunohistochemistry results. Here are specific challenges and their methodological solutions:

• High background staining:

  • Increase blocking stringency using 3-5% BSA or normal serum

  • Reduce primary antibody concentration (try 1:500-1:1000 dilutions)

  • Add 0.1-0.3% Triton X-100 to reduce non-specific membrane binding

  • Include avidin/biotin blocking step if using biotin-based detection systems

• Weak or inconsistent staining:

  • Optimize epitope retrieval conditions (test both citrate pH 6.0 and EDTA pH 9.0 buffers)

  • Extend primary antibody incubation (overnight at 4°C)

  • Use signal amplification systems like tyramide signal amplification

  • Ensure tissue fixation is optimized (prolonged fixation can mask epitopes)

• False negative results:

  • Verify kidney tissue sections contain tubular regions where FAM151A is expressed

  • Include positive control slides in each batch

  • Test multiple antibody clones targeting different epitopes

  • Consider membrane permeabilization enhancement for transmembrane protein access

• False positive interpretation:

  • Run parallel sections with isotype control antibodies

  • Include peptide competition controls to confirm specificity

  • Use CRISPR knockout tissue controls when available

  • Compare staining pattern with published expression data (kidney tubules)

• Inconsistent results between experiments:

  • Standardize tissue processing and storage conditions

  • Use automated staining platforms where available

  • Document all protocol parameters including lot numbers

  • Prepare master mixes of antibody dilutions for batch consistency

These methodological refinements address the specific challenges faced when detecting transmembrane proteins like FAM151A in tissue sections .

How should researchers interpret subcellular localization data for FAM151A?

Proper interpretation of FAM151A subcellular localization data requires understanding of the protein's structural features and expected distribution patterns:

• Expected localization pattern:

  • Primary localization should be at cellular membranes, consistent with FAM151A's transmembrane domain structure

  • Look for enrichment in plasma membrane or possibly specialized membrane compartments in kidney tubular cells

  • Potential presence in vesicular structures may indicate trafficking or recycling

• Co-localization analysis methodology:

  • Combine FAM151A immunostaining with established markers for:

    • Plasma membrane (Na⁺/K⁺-ATPase)

    • Endoplasmic reticulum (calnexin)

    • Golgi apparatus (GM130)

    • Endosomes (EEA1, Rab proteins)

  • Calculate Pearson's or Manders' coefficients to quantify co-localization

  • Use super-resolution microscopy for precise membrane localization

• Dynamic localization considerations:

  • Monitor potential redistribution following cellular stimulation

  • Assess internalization rates using surface biotinylation assays

  • Evaluate protein turnover using pulse-chase experiments

• Interpretation challenges:

  • Distinguish between specific signal and background fluorescence using appropriate controls

  • Consider fixation artifacts that can alter membrane protein distribution

  • Be aware that overexpression systems may lead to mislocalization

  • Account for tissue-specific variations in processing and trafficking

• Functional correlation:

  • Relate observed localization to FAM151A's proposed function in signaling pathways

  • Connect subcellular distribution to its evolutionary relationship with menorin and dendrite development

  • Consider how localization patterns might inform potential interactions with GDPD/PLCD superfamily members

This integrated approach to localization data provides context for functional hypotheses about FAM151A's role in kidney physiology .

How can researchers design experiments to elucidate FAM151A protein-protein interactions?

To comprehensively map FAM151A protein-protein interactions, implement this multi-method experimental design:

• Proximity-based interactome mapping:

  • Apply BioID or APEX2 proximity labeling by fusing biotin ligase to FAM151A

  • Express in kidney cell lines (HEK293, RPTEC)

  • Purify biotinylated proteins and identify by mass spectrometry

  • Filter against control datasets to remove common contaminants

• Co-immunoprecipitation with mass spectrometry:

  • Use agarose-conjugated FAM151A antibodies for endogenous pulldowns

  • Perform reciprocal IPs with candidate interactors

  • Apply SILAC or TMT labeling for quantitative interaction profiling

  • Focus on kidney tubule-derived cellular models for physiological relevance

• Yeast two-hybrid screening:

  • Design baits based on individual domains (particularly the functional DUF2181 domain)

  • Screen against kidney-specific cDNA libraries

  • Validate positive hits with targeted Y2H assays

  • Exclude transmembrane domain from constructs to avoid technical artifacts

• In situ proximity detection:

  • Implement proximity ligation assays (PLA) for candidate interactors

  • Apply in kidney tissue sections to maintain physiological context

  • Quantify interaction signals in different tubular segments

  • Include appropriate negative controls for signal specificity

• Computational interaction prediction and validation:

  • Use structure prediction tools to model FAM151A domains

  • Apply molecular docking to assess interaction potential with candidates

  • Validate predicted interactions using mutational analysis

  • Focus on GDPD/PLCD superfamily members as potential functional partners

This multi-faceted approach enables robust identification of the FAM151A interactome, providing critical insights into its biological function .

What approaches should be used to investigate FAM151A's role in colorectal cancer risk?

To investigate FAM151A's potential role in colorectal cancer risk, particularly in relation to the significant SNP rs11206394 , implement these methodological approaches:

• Genetic association validation:

  • Perform case-control studies across diverse populations

  • Implement targeted genotyping of rs11206394 and surrounding haplotype blocks

  • Conduct meta-analysis of existing genome-wide association studies

  • Correlate genotypes with clinical outcomes and cancer subtypes

• Functional genomics assessment:

  • Apply CRISPR/Cas9 to introduce the risk allele in cellular models

  • Evaluate allele-specific effects on gene expression using reporter assays

  • Analyze chromatin accessibility and transcription factor binding at the SNP locus

  • Perform RNA-seq to identify downstream transcriptional changes

• Protein expression analysis in clinical samples:

  • Develop tissue microarrays of colorectal cancer specimens

  • Perform immunohistochemistry using validated FAM151A antibodies

  • Correlate protein levels with rs11206394 genotype

  • Compare expression between tumor and matched normal tissues

• Mechanistic investigation:

  • Assess effects of FAM151A modulation on colorectal cancer cell line phenotypes

  • Evaluate cellular behaviors (proliferation, migration, invasion)

  • Examine impacts on signaling pathways known to be dysregulated in colorectal cancer

  • Investigate potential alterations in membrane glycerophosphodiester processing

• In vivo model development:

  • Generate FAM151A knockout or risk-allele knockin mouse models

  • Assess spontaneous and chemically-induced colorectal cancer development

  • Evaluate changes in intestinal homeostasis and inflammatory responses

  • Conduct histopathological analysis of intestinal tissues

This comprehensive approach integrates genetic, molecular, cellular, and in vivo methodologies to elucidate FAM151A's contribution to colorectal cancer pathogenesis .

How might researchers investigate the evolutionary conservation of FAM151A function across species?

To systematically investigate the evolutionary conservation of FAM151A function, implement these comparative methodological approaches:

• Phylogenetic analysis and structural comparison:

  • Construct comprehensive phylogenetic trees of FAM151A orthologs across species

  • Perform multiple sequence alignments focusing on the conserved DUF2181 domains

  • Apply structural prediction tools to assess conservation of protein folding

  • Compare with the C. elegans menorin protein to identify functionally critical residues

• Cross-species expression pattern analysis:

  • Utilize species-specific FAM151A antibodies or develop new ones as needed

  • Compare tissue distribution patterns across mammals, fish, and invertebrates

  • Document kidney tubule expression conservation across vertebrates

  • Note the absence in birds as a significant evolutionary event

• Functional complementation experiments:

  • Express human FAM151A in model organisms with FAM151A/menorin mutations

  • Assess rescue of phenotypes in C. elegans menorin mutants

  • Examine functional conservation in zebrafish FAM151A knockouts

  • Compare with FAM151B to understand paralog functional divergence

• Domain-swapping experiments:

  • Create chimeric proteins with domains from different species

  • Focus on the potentially non-functional second DUF2181 domain

  • Express in knockout cellular backgrounds

  • Assess restoration of molecular and cellular functions

• Comparative interactome analysis:

  • Identify conserved interaction partners across species

  • Focus on core functional modules preserved throughout evolution

  • Compare with menorin interactors in nematodes to understand functional conservation

  • Develop an evolutionary model of FAM151A functional adaptation

This multi-dimensional approach provides insights into the evolutionary history of FAM151A while highlighting functionally critical regions that have been maintained through selective pressure, offering clues about its fundamental biological roles .