adgrv1 Antibody

Which tissues express ADGRV1 at detectable levels for antibody-based studies?

ADGRV1 is expressed almost ubiquitously in many tissues, with strongest expression in the developing and mature nervous system. Among brain cells, ADGRV1 is most strongly expressed in astrocytes . It is also abundantly expressed in the retina, inner ear, and various regions of the brain . When designing immunohistochemistry experiments, prioritize these tissues for optimal signal detection.

What are the recommended primary antibodies for ADGRV1 detection in different applications?

Based on published research, several antibodies have been validated for ADGRV1 detection:

For co-localization studies, these antibodies have been successfully used alongside other markers including vinculin, paxillin, and zyxin .

What is the recommended protocol for immunostaining ADGRV1 in tissue sections?

For optimal results when immunostaining ADGRV1 in tissue sections:

• Fix tissues appropriately (paraformaldehyde fixation is commonly used)

• Perform antigen retrieval if necessary

• Block in AppliChem blocking reagent for 1 hour

• Incubate with primary anti-ADGRV1 antibody overnight at 4°C

• Wash three times with PBS

• Incubate with appropriate secondary antibodies (Alexa Fluor conjugates) for 1 hour at room temperature

• Counterstain nuclei with DAPI if desired

This protocol has been validated for detecting ADGRV1 in stereocilia and other cellular structures .

How can I distinguish between the N-terminal fragment (NTF) and C-terminal fragment (CTF) of ADGRV1 using antibodies?

ADGRV1 is autoproteolytically processed at its GAIN domain, dividing the molecule into an N-terminal fragment (NTF) and a C-terminal fragment (CTF) . To distinguish between these fragments:

• Select antibodies targeting specific domains:

  • For NTF detection: Use antibodies targeting the extracellular domains (Calx-β, LamG/PTX, or EPTP/EAR domains)

  • For CTF detection: Use antibodies targeting the 7TM domain or intracellular domain

• Verify fragment-specific detection by:

  • Using Adgrv1-del7TM mouse models (lacking the 7TM domain)

  • Using Y6236fsX1 mutant models (C-terminal truncation)

  • Comparing results with full-length and fragment-specific controls

Note that in Vlgr1/del7TM mice, only the extracellular domain is expressed , making these excellent controls for antibody specificity testing.

What are the recommended approaches for resolving contradictory immunostaining results with different ADGRV1 antibodies?

When facing contradictory results with different ADGRV1 antibodies:

• Compare epitope locations:

  • Different antibodies may target different domains of this large protein

  • Domain-specific accessibility may vary between tissue types and fixation methods

• Validate with genetic models:

  • Use ADGRV1-deficient models as negative controls (Adgrv1-del7TM, Y6236fsX1)

  • Compare results with siRNA knockdown experiments

• Perform epitope competition assays:

  • Pre-incubate antibody with purified antigen or peptide

  • Loss of signal confirms specificity

• Apply multiple detection methods:

  • Complement immunostaining with Western blotting or RT-qPCR

  • Reduced transcript levels in mutant models can validate protein-level findings

How can I perform proximity ligation assays (PLAs) to study ADGRV1 interactions with focal adhesion proteins?

Proximity ligation assays have been successfully used to confirm ADGRV1's integration into focal adhesion complexes . The methodology includes:

• Cell preparation:

  • Grow cells on appropriate substrate (coverslips)

  • Fix cells with 4% paraformaldehyde

  • Permeabilize with 0.2% Triton X-100

• PLA protocol:

  • Incubate with primary antibody pairs (e.g., ADGRV1/vinculin, ADGRV1/paxillin, or ADGRV1/zyxin)

  • Apply PLA probes specific to the primary antibody species

  • Perform ligation and amplification according to manufacturer's protocol

  • Counterstain for F-actin to visualize cytoskeletal context

• Controls:

  • Omit primary antibodies as negative control

  • Use established protein interactions as positive control

• Analysis:

  • Quantify PLA interaction spots in relation to F-actin termini

  • Compare signal distribution between experimental and control conditions

This approach has revealed VLGR1/ADGRV1 localization near F-actin termini within focal adhesion complexes .

What control samples should be included when investigating ADGRV1 expression in disease models?

When designing experiments to investigate ADGRV1 expression in disease models, include these controls:

• Genetic controls:

  • Wild-type (WT) tissues of identical background strain

  • Heterozygous models when available (for gene dosage effects)

  • Multiple types of ADGRV1 mutants if possible (e.g., both Vlgr1-del7TM and Drum B mutants)

• Cellular controls:

  • ADGRV1 siRNA knockdown cells

  • CRISPR/Cas9-edited cell lines

  • USH2C patient-derived fibroblasts for human disease relevance

• Technical controls:

  • Secondary antibody-only controls

  • Non-related IgG controls of same species as primary antibody

  • Peptide competition assays to verify antibody specificity

The search results specifically mention using C57BL/6 strain mice as wild-type controls for Adgrv1/del7TM mice , and comparing homozygous and heterozygous Y6236fsX1 mutant mice .

How should I design experiments to investigate ADGRV1's role in astrocyte glutamate homeostasis?

Based on recent findings about ADGRV1's role in astrocytic glutamate homeostasis , consider this experimental design:

• Model systems:

  • Primary astrocyte cultures from Adgrv1-deficient mice (Adgrv1/del7TM)

  • Patient-derived cells carrying ADGRV1 mutations

  • ADGRV1 knockdown in established astrocyte cell lines

• Key measurements:

  • Glutamate uptake using colorimetric assays

  • Live-cell imaging with genetic glutamate reporters

  • Expression analysis of glutamate-glutamine cycle enzymes

  • Astrocyte morphology assessment via GFAP and SOX9 immunostaining

• Experimental controls:

  • Wild-type astrocytes of matching developmental stage

  • Rescue experiments with ADGRV1 expression constructs

  • Positive controls using established glutamate uptake inhibitors

• Antibodies required:

  • Anti-ADGRV1 for validation of knockout/knockdown

  • Anti-GFAP for astrocyte identification

  • Anti-SOX9 for astrocyte nuclear marker

  • Anti-GLAST for glutamate transporter analysis

  • Anti-Glutamine synthetase for glutamate metabolism

This approach has successfully demonstrated that "glutamate uptake from the extracellular environment is significantly reduced in Adgrv1-deficent astrocytes" .

What methodology should be used for tandem affinity purification (TAP) to identify ADGRV1 interacting proteins?

TAP has been successfully used to identify ADGRV1 interacting proteins in multiple studies . The recommended methodology includes:

• Construct design:

  • Create Strep II-FLAG (SF)-tagged ADGRV1 constructs

  • Consider both full-length ADGRV1a and domain-specific constructs:

    • ADGRV1_CTF (aa 5891-6306)

    • ADGRV1_ICD (aa 6155-6306)

• Expression system:

  • Transfect hTERT-RPE1 cells with the SF-tagged constructs

  • Alternative: HEK293T cells for overexpression studies

• Purification protocol:

  • Apply SF-TAP methodology

  • Analyze eluted complexes by liquid chromatography coupled with tandem mass spectrometry

  • Use software tools like SAINT for annotation of proteomic data sets

• Validation:

  • Confirm key interactions by co-immunoprecipitation

  • Verify with proximity ligation assays

  • Compare interactomes between different ADGRV1 constructs and other USH proteins like CIB2

This approach has identified important ADGRV1 interactions with focal adhesion proteins , autophagy components , and G-proteins .

How can I quantitatively assess ADGRV1 localization in subcellular compartments?

To quantitatively assess ADGRV1 subcellular localization:

• Imaging approach:

  • Acquire high-resolution confocal images

  • Use appropriate markers for subcellular compartments:

    • Focal adhesions: Vinculin, paxillin, or zyxin

    • Stereocilia: F-actin

    • Endoplasmic reticulum: Calnexin

    • Mitochondria-associated ER membranes (MAMs): Use established markers

• Quantification methods:

  • Measure colocalization with Pearson's or Mander's coefficients

  • Calculate percentage of ADGRV1 signal overlapping with compartment markers

  • Measure intensity profiles along defined cellular axes

• Analysis software:

  • ImageJ/FIJI with Coloc2 plugin

  • CellProfiler for automated high-throughput analysis

  • Specialized software like Imaris for 3D reconstruction

• Statistical approach:

  • Compare multiple cells across experimental conditions

  • Use appropriate statistical tests based on data distribution

  • Report both mean/median values and measures of variation

This approach has been used to demonstrate ADGRV1 localization in focal adhesions, at F-actin termini, and in specialized structures like ankle links in stereocilia .

What are the considerations when analyzing transcriptomic data from ADGRV1-deficient models?

When analyzing transcriptomic data from ADGRV1-deficient models , consider:

• Experimental design validation:

  • Confirm ADGRV1 expression reduction by RT-qPCR

  • Check for nonsense-mediated decay of mutant transcripts

  • Validate key findings with protein-level measurements

• Analytical approaches:

  • Focus on pathways relevant to known ADGRV1 functions:

    • Glutamate homeostasis genes

    • Autophagy-related genes

    • Focal adhesion and cytoskeletal organization genes

    • G-protein signaling pathways

  • Perform Gene Ontology (GO) enrichment analysis

  • Network analysis to identify affected protein complexes

• Validation strategies:

  • Compare findings across different models:

    • Patient-derived cells vs. mouse models

    • Different anatomical regions (hippocampus vs. retina)

  • Validate key differentially expressed genes with RT-qPCR

  • Confirm corresponding protein changes by immunoblotting

• Interpretation frameworks:

  • Interpret results in context of disease mechanisms (USH, epilepsy)

  • Consider developmental timepoints when analyzing data

  • Compare with published datasets for related disorders

This approach has revealed altered expression profiles of genes related to glutamate homeostasis and autophagy in ADGRV1-deficient models.

How should contradictory findings about ADGRV1's G-protein coupling be resolved experimentally?

Research has revealed potentially contradictory findings about ADGRV1's G-protein coupling preferences . To resolve these experimentally:

• Construct-specific analysis:

  • Compare full-length ADGRV1a vs. ADGRV1_CTF coupling preferences

  • Investigate if proteolytic processing affects coupling specificity

  • Create domain-specific mutants to map determinants of G-protein specificity

• Signaling assays:

  • Measure cAMP production (for Gαs coupling)

  • Assess IP accumulation (for Gαq coupling)

  • Evaluate inhibition of forskolin-stimulated cAMP (for Gαi coupling)

  • Employ BRET or FRET assays for direct coupling measurement

• Controls and validation:

  • Include positive controls for each G-protein pathway

  • Use specific G-protein inhibitors as validation

  • Confirm findings in multiple cell types

• Developmental and contextual analysis:

  • Investigate if coupling preferences change during development

  • Examine if cellular context alters coupling preference

  • Study if mechanical stimulation alters coupling (relevant to ADGRV1's mechanosensing role)

The data presented in the search results suggests "a signaling switch from basal Gs to active Gi" for ADGRV1 , which could explain seemingly contradictory findings if not carefully controlled for experimental conditions.

What methodological approaches can detect the autoproteolytic processing of ADGRV1 at the GAIN domain?

ADGRV1, like other adhesion GPCRs, can be autoproteolytically processed at its GAIN domain . To detect this processing:

• Western blot approach:

  • Use antibodies targeting domains on either side of the GPS cleavage site

  • Run samples under non-reducing conditions to preserve non-covalent associations

  • Compare to mutants with disrupted GPS cleavage sites

• Mass spectrometry:

  • Perform immunoprecipitation with domain-specific antibodies

  • Identify peptides corresponding to cleaved fragments

  • Quantify relative abundance of cleaved vs. uncleaved forms

• Microscopy-based approaches:

  • Use differentially tagged constructs (N-terminal and C-terminal tags)

  • Apply proximity ligation assays to detect intact vs. separated fragments

  • Perform FRET analysis to monitor conformational changes

• Functional validation:

  • Compare signaling properties of cleavable vs. non-cleavable mutants

  • Assess mechanical activation in relation to proteolytic processing

  • Evaluate interaction partners specific to cleaved or uncleaved forms

These approaches can help understand how "mechanosensation of ADGRV1 may trigger its cleavage and subsequent receptor activation by the tethered 'Stachel' agonist inducing the switch from Gαs-to Gαi-mediated signaling" .

How can antibody-based techniques help understand ADGRV1's role in USH2 protein complex formation?

ADGRV1 (USH2C) functions in complex with other Usher syndrome proteins. To study these complexes:

• Co-immunoprecipitation strategies:

  • Immunoprecipitate ADGRV1 to co-capture USH2A and WHRN

  • Use epitope-tagged constructs (Myc-WHRN, Flag-ADGRV1)

  • Compare wild-type vs. mutant forms (e.g., ADGRV1 Y6236fsX1)

• Proximity detection methods:

  • Apply PLA to detect native protein complexes in situ

  • Use FRET or BRET for dynamic interaction studies

  • Implement BioID or APEX2 proximity labeling

• Localization studies:

  • Perform whole-mount immunostaining of cochlear hair cells

  • Track stereocilia localization in wild-type vs. Adgrv1 mutants

  • Assess ankle-link complex (ALC) formation using super-resolution microscopy

• Functional validation:

  • Express truncated forms lacking the PDZ-binding motif

  • Study scaffold function of WHRN in complex formation

  • Assess impact of disease-causing mutations on complex stability

This approach has demonstrated that "the ADGRV1 Y6236fsX1 mutant affects ALC formation" and that "WHRN serves as the scaffold for the ternary complex through its concurrent binding to both ADGRV1 and USH2A" .