adgra3 Antibody

What is ADGRA3 and why is it important in research?

ADGRA3, also known as adhesion G protein-coupled receptor A3 or G-protein coupled receptor 125 (GPR125), is a protein encoded by the human GPR125 gene. As a member of the adhesion G protein-coupled receptor family, ADGRA3 has a long extracellular subunit with protein-protein interacting domains and a GPCR subunit. The last four amino acids (ETTV) of Gpr125 constitute a PDZ-binding motif, which is also found in the transmembrane PCP pathway components Frizzled and Vangl2 . Recent research indicates that ADGRA3 exhibits high expression levels in brown adipose tissue (BAT) and may participate in inducing adipose thermogenesis, making it a promising target for metabolic research . Understanding ADGRA3's function is particularly valuable for researchers investigating adipose tissue biology, energy metabolism, and related disorders.

What are the basic characteristics of commercially available ADGRA3 antibodies?

ADGRA3 antibodies are available for various research applications, with specific characteristics optimized for different detection methods. For immunohistochemistry, antibodies like anti-ADGRA3 (1:200; 11912-1-AP) have been successfully employed in published research . Western blot applications typically use anti-ADGRA3 antibodies at a 1:1000 dilution . The antibodies target specific epitopes of the ADGRA3 protein, which has a total length of 1321 amino acids and contains 7 transmembrane domains . When selecting an ADGRA3 antibody, researchers should consider the specific application, species reactivity (human vs. mouse), clonality (monoclonal vs. polyclonal), and the particular domain of ADGRA3 being targeted.

What tissue types express ADGRA3 at detectable levels?

ADGRA3 expression shows tissue specificity with notable patterns. Research has demonstrated that ADGRA3 is predominantly expressed in adipocytes, with significantly higher expression levels in brown adipose tissue (BAT) adipocytes compared to white adipose tissue (WAT) adipocytes . In contrast, the expression level of ADGRA3 in the stromal vascular fraction (SVF) shows no significant difference between WAT and BAT . Expression profiling has revealed that ADGRA3 follows a similar expression pattern to UCP1 (a key marker of brown/beige adipocytes) during differentiation in both mouse and human adipocytes . When planning experiments involving ADGRA3 antibodies, researchers should prioritize adipose tissues, particularly BAT, as primary targets for investigation.

What are the recommended protocols for ADGRA3 antibody use in immunohistochemistry?

For successful immunohistochemistry (IHC) using ADGRA3 antibodies, researchers should follow a protocol that has been validated in peer-reviewed research. Based on published methodologies, tissue slides should first be blocked with goat serum for 1 hour to reduce non-specific binding. Following blocking, incubate the slides with anti-ADGRA3 antibody (at a 1:200 dilution; 11912-1-AP) overnight at 4°C . Detection should be performed using an appropriate secondary antibody system such as EnVision Detection Systems, with hematoxylin as a counterstain . This approach has successfully visualized ADGRA3 in adipose tissues. For optimal results, include positive controls (BAT samples) and negative controls (antibody omission) to validate specificity.

How can ADGRA3 antibodies be used to investigate the role of ADGRA3 in adipose thermogenesis?

ADGRA3 has emerged as a significant factor in adipose thermogenesis and beige adipocyte formation. To investigate this role, researchers can employ a multi-faceted approach using ADGRA3 antibodies. Western blot analysis using ADGRA3 antibodies can quantify protein expression in different adipose depots (BAT vs. WAT) and under various experimental conditions (cold exposure, β-adrenergic stimulation) . For spatial distribution assessment, immunohistochemistry with ADGRA3 antibodies can be performed in parallel with UCP1 staining on sequential sections to establish co-localization patterns .

A comprehensive investigation should combine protein detection with functional readouts. Researchers have successfully correlated ADGRA3 expression levels (detected via antibodies) with thermogenic capacity measurements including oxygen consumption rate (OCR), mitochondrial content (via Mito-Tracker staining), and lipid droplet morphology . For mechanistic studies, ADGRA3 antibodies can be used to monitor protein expression after genetic manipulation (overexpression or knockdown) of Adgra3, revealing the consequent effects on downstream signaling proteins like phosphorylated CREB (p-CREB) .

What methodological approaches should be used when studying ADGRA3's interaction with the PKA-CREB signaling pathway?

ADGRA3 has been demonstrated to activate the PKA-CREB signaling pathway, which is critical for understanding its functional role in adipose tissues. To investigate this interaction, researchers should implement a coordinated experimental approach. Western blot analysis using antibodies against both ADGRA3 and phosphorylated CREB (p-CREB) should be performed to establish correlation between ADGRA3 expression levels and PKA pathway activation . This relationship can be further confirmed through genetic manipulation experiments, where overexpression of Adgra3 increases p-CREB levels while knockdown reduces p-CREB expression .

For more detailed mechanistic insights, researchers should employ pharmacological inhibitors alongside antibody detection. Treatment with PKA inhibitors (such as H-89) followed by Western blot analysis for ADGRA3, p-CREB, and downstream targets like UCP1 can reveal the dependence of ADGRA3's effects on PKA signaling . Additionally, knockdown of Gαs (encoded by Gnas) combined with ADGRA3 overexpression, followed by antibody detection of signaling components, can determine whether ADGRA3 signals through G protein-coupled mechanisms . This comprehensive approach has successfully demonstrated that ADGRA3's thermogenic effects are mediated through the PKA-CREB signaling pathway in adipocytes.

How can researchers address potential cross-reactivity issues with ADGRA3 antibodies?

Cross-reactivity remains a significant challenge when working with antibodies against G protein-coupled receptors like ADGRA3, due to structural similarities within this protein family. To address this issue, researchers should implement a multi-faceted validation strategy. First, conduct specificity testing through Western blot analysis using samples with Adgra3 knockdown and overexpression to confirm that antibody signal changes proportionally with experimental manipulation of the target protein .

For immunohistochemistry applications, researchers should perform parallel staining with multiple antibodies targeting different epitopes of ADGRA3 to confirm concordant localization patterns. Additionally, pre-absorption tests using the immunizing peptide can validate specificity by demonstrating signal reduction. When possible, orthogonal validation using gene expression analysis (qPCR) should be performed to confirm that protein levels detected by antibodies correlate with mRNA expression patterns across tissues and experimental conditions .

Finally, researchers should consider species-specific validation when working with both human and mouse models, as antibody performance may vary between species despite high sequence homology. Published studies have successfully used this approach to confirm ADGRA3 antibody specificity in adipose tissue samples .

What are the recommended protocols for quantifying ADGRA3 protein levels in adipose tissue samples?

Accurate quantification of ADGRA3 protein levels in adipose tissue requires optimized protocols that account for the unique characteristics of these samples. For Western blot analysis, adipose tissues should be lysed in RIPA buffer supplemented with 1 mM PMSF and protease inhibitor cocktail . Protein concentration determination using BCA protein assay is recommended, with standardized loading of 25 μg total protein per lane . For ADGRA3 detection, use primary antibody at 1:1000 dilution, with appropriate housekeeping controls such as HSP90 (1:1000) or α-tubulin (1:10000) .

For accurate quantification across different adipose depots, researchers should implement a standardized tissue collection and processing protocol. Isolated stromal vascular fraction (SVF) and mature adipocytes should be analyzed separately to determine cell-specific expression patterns . When comparing different depot types (BAT vs. WAT), normalization to total protein is preferred over housekeeping genes due to potential variation in reference protein expression across adipose tissue types.

Digital image analysis of Western blots should employ standardized exposure settings and calibration standards for densitometry measurements. For statistical validity, biological replicates (n≥3) and technical replicates should be included, with data presented as mean ± standard deviation or standard error.

How should researchers interpret discrepancies between ADGRA3 mRNA and protein expression data?

Discrepancies between mRNA and protein expression are common in GPCR research, including studies of ADGRA3. When encountering such discrepancies, researchers should consider several interpretive frameworks. Post-transcriptional regulation mechanisms may explain these differences, including microRNA regulation, RNA stability differences, or alternative splicing. Post-translational modifications and protein stability factors may also contribute to differences between mRNA and protein levels.

To systematically address these discrepancies, researchers should implement time-course studies measuring both mRNA (via qPCR) and protein (via Western blot with ADGRA3 antibodies) during adipocyte differentiation or following experimental manipulations . This approach has revealed that ADGRA3 mRNA and protein levels follow similar patterns during adipocyte differentiation, though with temporal differences .

What controls should be included when using ADGRA3 antibodies in adipose tissue research?

Robust experimental design for ADGRA3 antibody research requires comprehensive controls to ensure validity and reproducibility. Researchers should include positive tissue controls (BAT samples with confirmed high ADGRA3 expression) and negative tissue controls (tissues with minimal ADGRA3 expression) in every experiment . For antibody validation, technical negative controls should include primary antibody omission and isotype controls to assess non-specific binding.

Genetic controls are particularly valuable, incorporating samples from Adgra3 knockdown and overexpression experiments to confirm antibody specificity and dynamic range . When possible, include tissue samples from Adgra3 knockout models as gold-standard negative controls. For Western blot applications, recombinant ADGRA3 protein can serve as a positive control for antibody specificity and size verification.

When studying thermogenic effects, parallel samples should be processed for both ADGRA3 and UCP1 detection to establish functional correlations . Additionally, physiological controls comparing animals exposed to different conditions (thermoneutrality vs. cold exposure) can validate antibody performance across biologically relevant expression ranges. This comprehensive control strategy has been successfully implemented in published studies investigating ADGRA3's role in adipose tissue biology .

How can researchers determine if ADGRA3 antibody is suitable for co-immunoprecipitation studies?

Determining an ADGRA3 antibody's suitability for co-immunoprecipitation (co-IP) requires systematic validation beyond manufacturer specifications. Researchers should first confirm the antibody's ability to recognize native, non-denatured ADGRA3 through techniques like immunofluorescence or flow cytometry, since Western blot validation alone is insufficient for co-IP applications.

A pilot co-IP experiment should be performed using tissue or cells with confirmed high ADGRA3 expression (such as BAT), followed by Western blot analysis of the immunoprecipitated material using the same or a different ADGRA3 antibody targeting a distinct epitope . Successful immunoprecipitation of ADGRA3 itself is a prerequisite for interaction studies.

For comprehensive validation, researchers should perform reciprocal co-IP experiments with antibodies against known or predicted ADGRA3-interacting proteins. Based on ADGRA3's role in PKA-CREB signaling, antibodies against G proteins (particularly Gαs) or components of the PKA complex would be appropriate for such validation . Additionally, testing the antibody in cells with Adgra3 overexpression and knockdown will confirm specificity and sensitivity in co-IP applications.

Finally, researchers should optimize co-IP conditions including buffer composition (detergent type and concentration), incubation time, and washing stringency to maintain native protein interactions while minimizing non-specific binding.

What methodological approaches should be employed when studying ADGRA3's constitutive activity?

ADGRA3 demonstrates constitutive activity that induces adipose thermogenesis, requiring specialized experimental approaches to characterize this activity. Researchers should implement a multi-parameter experimental design combining molecular and functional readouts. For signal transduction analysis, Western blot with phospho-specific antibodies targeting downstream effectors (particularly p-CREB) should be performed in cells expressing ADGRA3 with and without ligand stimulation . Comparison with other GPCRs that lack constitutive activity can serve as negative controls.

Pharmacological profiling using inverse agonists and neutral antagonists can help distinguish between constitutive activity and ligand-independent activation. Following treatment, ADGRA3 antibodies can be used to assess receptor expression levels and localization, while functional assays measure downstream effects. For adipocyte studies, measurement of basal and maximum oxygen consumption rates (OCR) using Seahorse technology has successfully demonstrated that ADGRA3 overexpression increases basal metabolic activity even without stimulation .

Mutation studies targeting the GPCR domains combined with antibody detection can identify regions critical for constitutive activity. This approach should be complemented with intracellular cAMP assays to directly measure second messenger production resulting from constitutive GPCR activity. Through these methodologies, researchers have established that ADGRA3 possesses intrinsic signaling capacity that promotes thermogenic programming in adipocytes .

How can ADGRA3 antibodies be used in studies comparing human and mouse adipose tissue?

Cross-species comparisons of ADGRA3 expression and function require careful methodological consideration. When using ADGRA3 antibodies across human and mouse samples, researchers should first verify cross-reactivity through sequence analysis of the epitope regions and validation testing on both species' samples. Western blot analysis may reveal species-specific differences in molecular weight due to post-translational modifications or splice variants.

A comprehensive experimental design should include parallel immunohistochemistry of human and mouse adipose tissue sections (both BAT and WAT) using standardized protocols . This approach has revealed that ADGRA3 expression patterns are conserved across species, with higher expression in brown/beige adipocytes compared to white adipocytes . When quantifying expression, normalization strategies should be consistent between species, preferably using multiple reference proteins that show stable expression across both human and mouse samples.

For functional studies, parallel differentiation experiments with human and mouse pre-adipocytes have demonstrated that ADGRA3 expression follows similar patterns during adipogenesis in both species . This approach, combined with antibody detection of ADGRA3 and UCP1, can establish whether the protein's role in thermogenesis is evolutionarily conserved. Published data indicate that modulation of ADGRA3/Adgra3 and UCP1/Ucp1 expression exhibits similar patterns during differentiation between mouse and human adipocytes .

What advanced techniques can be combined with ADGRA3 antibodies for studying protein-protein interactions?

Understanding ADGRA3's functional mechanisms requires sophisticated approaches to protein interaction analysis. Researchers can employ proximity ligation assays (PLA) using ADGRA3 antibodies paired with antibodies against potential interacting partners to visualize protein-protein interactions in situ with subcellular resolution. This technique is particularly valuable for membrane proteins like ADGRA3 that may form transient complexes at the cell surface.

For comprehensive interactome mapping, immunoprecipitation using ADGRA3 antibodies followed by mass spectrometry (IP-MS) can identify novel interaction partners in an unbiased manner. This approach should include appropriate controls such as IgG immunoprecipitation and samples with Adgra3 knockdown to distinguish specific from non-specific interactions .

Advanced imaging techniques including super-resolution microscopy (STORM/PALM) using fluorescently-labeled ADGRA3 antibodies can reveal nanoscale organization and clustering of ADGRA3 at the plasma membrane. For dynamic interaction studies, bioluminescence resonance energy transfer (BRET) or fluorescence resonance energy transfer (FRET) assays can be employed to monitor real-time interactions between ADGRA3 and other proteins in living cells.

Researchers studying ADGRA3's role in G protein signaling have successfully combined antibody detection with functional assays following genetic manipulation (Gαs knockdown) to establish that ADGRA3's effects on adipocyte thermogenesis are dependent on G protein signaling pathways .

How should researchers quantitatively analyze ADGRA3 expression across different adipose tissue depots?

Accurate quantitative analysis of ADGRA3 expression across adipose depots requires standardized methodologies and appropriate statistical approaches. The following table outlines a framework for comprehensive expression analysis:

What parameters should be considered when evaluating ADGRA3 antibody performance across different applications?

Comprehensive evaluation of ADGRA3 antibody performance requires assessment across multiple parameters and applications. The following table provides a framework for systematic antibody evaluation:

This evaluation framework incorporates validated protocols from published research, including the successful use of anti-ADGRA3 antibodies at 1:200 dilution for immunohistochemistry and 1:1000 dilution for Western blot applications . Researchers should systematically assess each parameter across different applications to determine the optimal conditions for their specific experimental questions, always including appropriate positive and negative controls for each application.