tmem150b Antibody

What is TMEM150B and what cellular functions does it serve?

TMEM150B (transmembrane protein 150B), also known as DRAM-related/associated member 3 (DRAM-3), belongs to the DRAM family which includes five members: DRAM-1, DRAM-2, and TMEM150A/B/C . It is a transmembrane protein with significant expression in mouse oocytes, though relatively low expression in diverse tissues including spleen, lung, kidney, testis, and ovary . Despite its notable expression in reproductive tissues, knockout studies have demonstrated that TMEM150B is dispensable for folliculogenesis, oocyte maturation, and female fertility in mice . The protein's precise cellular function remains under investigation, though genetic association studies have linked its gene variants with age at natural menopause, early menopause, and premature ovarian insufficiency (POI) .

What are the primary applications for TMEM150B antibodies in research?

TMEM150B antibodies are primarily utilized for protein detection through Western Blot (WB) and ELISA applications . They enable researchers to study TMEM150B expression patterns across different tissues, cell types, and developmental stages. While TMEM150 antibodies show reactivity with human, mouse, and rat samples, experimental validation is necessary when using these antibodies in specific model systems . These antibodies serve as essential tools for investigating TMEM150B's role in cellular processes, particularly in reproductive biology and potentially in pathways related to cellular stress responses, given its relationship to the DRAM family.

What is the molecular weight of TMEM150B and how does this affect antibody selection?

TMEM150B has a calculated molecular weight of approximately 29 kDa based on its amino acid sequence (271 amino acids), though the observed molecular weight in experimental conditions is approximately 33 kDa . This discrepancy between calculated and observed weights may be attributed to post-translational modifications such as glycosylation or phosphorylation. When selecting antibodies, researchers should consider this variation and verify that the antibody recognizes the appropriately sized band in their experimental system. Antibodies that detect bands at unexpected molecular weights should be validated through additional methods such as immunoprecipitation followed by mass spectrometry or using knockout controls to confirm specificity.

What is the optimal protocol for using TMEM150B antibodies in Western Blotting?

For optimal Western Blot detection of TMEM150B, researchers should follow these methodological steps:

• Sample preparation: Extract proteins using appropriate lysis buffers containing protease inhibitors to prevent degradation. For TMEM150B, RIPA buffer containing 1% NP-40, 0.5% sodium deoxycholate, 0.1% SDS, and protease inhibitor cocktail is generally effective.

• Protein separation: Separate 20-40 μg of protein on 10-12% SDS-PAGE gels, as TMEM150B has an observed molecular weight of 33 kDa .

• Transfer and blocking: Transfer proteins to PVDF membranes using standard transfer systems and block with 5% non-fat dry milk in TBST for 1 hour at room temperature.

• Primary antibody incubation: Dilute TMEM150B antibody at 1:500-1:1000 in blocking buffer and incubate overnight at 4°C . Washing steps should include 3-5 washes with TBST for 5-10 minutes each.

• Secondary antibody and detection: Incubate with HRP-conjugated secondary antibodies (anti-rabbit IgG for polyclonal antibodies) at appropriate dilutions (typically 1:5000-1:10000) for 1 hour at room temperature. Develop using ECL substrate and image using standard chemiluminescence detection systems.

• Controls: Include positive controls (tissues known to express TMEM150B, such as oocytes) and negative controls (either tissues with low expression or knockout samples when available) .

The recommended dilution range for TMEM150B antibody in Western Blot applications is 1:500-1:1000, though this should be optimized for each experimental system .

How can researchers validate the specificity of TMEM150B antibodies?

Validating antibody specificity is crucial for reliable research outcomes. For TMEM150B antibodies, implement these validation approaches:

• Genetic models: Utilize TMEM150B knockout mouse models or CRISPR/Cas9-edited cell lines lacking TMEM150B expression as negative controls . Compare antibody reactivity between wild-type and knockout samples to confirm specificity.

• siRNA knockdown: Perform transient knockdown of TMEM150B using specific siRNAs and verify reduced signal via Western blot compared to non-targeting controls.

• Blocking peptides: Pre-incubate the antibody with excess immunizing peptide prior to application in Western blot or immunostaining to demonstrate competitive inhibition of specific binding.

• Cross-reactivity assessment: Test the antibody against related family members (TMEM150A, TMEM150C) to ensure it does not cross-react with these homologous proteins. This is particularly important given the similarity between TMEM150 family members .

• Multiple antibodies approach: Compare results obtained with antibodies targeting different epitopes of TMEM150B to strengthen validity of findings.

Research publications have validated TMEM150B antibodies using knockout models, demonstrating complete absence of the specific 33 kDa band in knockout samples, confirming antibody specificity .

What considerations should be made when designing immunohistochemistry experiments with TMEM150B antibodies?

When designing immunohistochemistry (IHC) or immunofluorescence (IF) experiments with TMEM150B antibodies, researchers should consider:

• Fixation protocol: Optimize fixation conditions, as transmembrane proteins may require specific fixation protocols. Start with 4% paraformaldehyde fixation for 10-15 minutes for cultured cells or 24 hours for tissue sections.

• Antigen retrieval: Test different antigen retrieval methods (heat-induced epitope retrieval using citrate buffer pH 6.0 or EDTA buffer pH 9.0) to maximize epitope accessibility, particularly important for formalin-fixed paraffin-embedded tissues.

• Antibody dilution and incubation: Begin with manufacturer's recommended dilutions (typically 1:100-1:200 for IHC/IF) and optimize through titration experiments.

• Permeabilization: Since TMEM150B is a transmembrane protein, optimize membrane permeabilization using detergents like 0.1-0.3% Triton X-100 or 0.1% saponin to ensure antibody access to intracellular epitopes.

• Controls: Include positive control tissues known to express TMEM150B (such as oocytes) and negative controls (either tissues with low expression, knockout samples, or primary antibody omission) .

• Counterstaining: Use appropriate nuclear counterstains (DAPI, Hoechst) and consider co-staining with organelle markers to determine subcellular localization of TMEM150B.

• Confocal microscopy: Due to the transmembrane nature of TMEM150B, confocal microscopy may provide better resolution of membrane localization than conventional fluorescence microscopy.

How do TMEM150B expression patterns compare between different tissue types and what methods best capture these differences?

TMEM150B exhibits differential expression across tissues, with notably higher expression in oocytes compared to other tissues such as spleen, lung, kidney, testis, and ovary . To accurately capture these expression differences:

• Quantitative RT-PCR: Using validated primers (such as F: 5′-TTGCTGCCTGTCATCTTATTTC-3′, R: 5′-AGGTTTTGACGCCCCAGT-3′), researchers can quantify TMEM150B mRNA levels across tissues, normalizing to stable reference genes like GAPDH .

• Western blotting: Semi-quantitative assessment of protein expression using validated TMEM150B antibodies, with densitometric analysis normalized to loading controls like β-actin.

• RNA-seq analysis: For comprehensive transcriptomic profiling, RNA-seq provides unbiased assessment of TMEM150B expression across different tissues and conditions.

• Single-cell RNA-seq: For heterogeneous tissues, single-cell approaches can reveal cell type-specific expression patterns.

• Immunohistochemistry with quantitative image analysis: To assess spatial distribution and expression levels within complex tissues.

Research has demonstrated that using multiple complementary techniques provides the most comprehensive understanding of TMEM150B expression patterns. For example, qRT-PCR analysis showing high expression in oocytes has been confirmed through protein-level analysis via Western blotting .

What is known about the relationship between TMEM150B and other TMEM150 family members, and how can researchers distinguish between them?

TMEM150B belongs to a family that includes TMEM150A, TMEM150C, and is related to the DRAM family (DRAM-1, DRAM-2) . Key considerations for distinguishing between family members include:

• Sequence homology and structural differences: TMEM150 family members share sequence homology but differ in specific domains. Researchers should perform sequence alignment analysis to identify unique regions for targeting with specific antibodies or primers.

• Expression pattern differences: While TMEM150B shows high expression in oocytes, TMEM150A appears to be involved in immune regulation, particularly in TLR4 signaling and cytokine production . Researchers should consider these distinct tissue and functional distributions when designing experiments.

• Functional redundancy: Studies suggest possible functional redundancy among family members, which may explain why TMEM150B knockout mice show no obvious reproductive phenotypes . To address this, researchers may need to generate double or triple knockout models.

• Antibody cross-reactivity: Carefully validate antibodies using knockout controls to ensure they specifically detect the intended TMEM150 family member without cross-reactivity. Western blots should show bands of the appropriate molecular weight (33 kDa for TMEM150B) .

• Isoform-specific primers: Design and validate PCR primers that target unique regions of each family member to ensure specificity in expression analysis.

Advanced researchers investigating TMEM150 family members should consider comprehensive approaches such as simultaneous knockdown experiments to address potential compensatory mechanisms between family members.

What is the current understanding of TMEM150B's role in reproductive biology, and what experimental approaches have been most informative?

Current research indicates that despite its high expression in oocytes, TMEM150B appears dispensable for female fertility in mice . Key experimental approaches that have informed this understanding include:

• Genetic knockout models: CRISPR/Cas9-mediated deletion of TMEM150B exons 2-4 in mice has been the most definitive approach, demonstrating normal oocyte maturation, follicular development, and fertility in knockout females .

• Phenotypic characterization: Comprehensive assessment of:

  • Oocyte meiotic maturation (polar body extrusion rates)

  • Spindle morphology via immunofluorescence

  • Follicular development through histological examination

  • Estrous cycle tracking via vaginal cytology

  • Fertility testing (litter size, frequency, time to first litter)

  • Hormonal profiling (FSH, E2 levels)

• Expression analysis: qRT-PCR and protein detection methods have established the spatiotemporal expression pattern of TMEM150B during folliculogenesis and oocyte maturation .

The most striking finding from these approaches is the disconnect between high expression and apparent dispensability for function, as summarized in the following fertility data from knockout studies:

This data demonstrates no significant differences in fertility parameters between wild-type and TMEM150B knockout mice .

Future research directions may include investigating:

• Potential roles under stress conditions not captured in standard laboratory environments

• Possible compensatory mechanisms involving other TMEM150 family members

• Species-specific differences in TMEM150B function between mice and humans

What are common obstacles in TMEM150B detection and how can researchers overcome them?

Researchers working with TMEM150B antibodies may encounter several technical challenges:

• Low signal intensity: TMEM150B has relatively low expression in many tissues except oocytes . To overcome:

  • Increase protein loading (50-100 μg per lane)

  • Optimize antibody concentration through titration experiments

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

  • Use high-sensitivity ECL substrates for Western blot detection

  • Consider sample enrichment through immunoprecipitation prior to Western blotting

• Multiple bands or non-specific binding: To improve specificity:

  • Increase blocking stringency (5% BSA instead of milk for phospho-specific detection)

  • Optimize antibody dilution (start with 1:500-1:1000)

  • Increase washing duration and number of washes

  • Pre-adsorb antibody with lysates from TMEM150B knockout samples

  • Validate using knockout controls to identify the specific band

• Membrane protein extraction challenges: As a transmembrane protein, TMEM150B may require specialized extraction:

  • Use detergent-based buffers containing NP-40, Triton X-100, or digitonin

  • Avoid freeze-thaw cycles which can disrupt membrane protein integrity

  • Consider membrane protein enrichment protocols prior to Western blotting

• Cross-reactivity with other TMEM150 family members: To ensure specificity:

  • Validate antibodies using knockout controls for each family member

  • Select antibodies raised against unique epitopes not conserved among family members

  • Confirm findings using multiple antibodies targeting different regions of the protein

• Fixation-sensitive epitopes in IHC/IF: Test multiple fixation protocols if initial attempts yield poor results.

How can researchers integrate TMEM150B studies with broader signaling pathway investigations?

To place TMEM150B within broader cellular signaling networks, researchers can employ these approaches:

• Co-immunoprecipitation studies: Identify protein-protein interactions by immunoprecipitating TMEM150B and analyzing binding partners via mass spectrometry or Western blotting for suspected interactors.

• Proximity labeling approaches: BioID or APEX2 fusion proteins can identify proximal proteins in living cells, providing insights into the TMEM150B interactome.

• Phosphoproteomics: Compare phosphorylation states in wild-type versus TMEM150B knockout/knockdown systems to identify affected signaling pathways.

• Transcriptome analysis: RNA-seq comparing wild-type and TMEM150B-deficient cells can reveal downstream transcriptional effects and implicated pathways.

• Functional assays targeting related pathways: Given that TMEM150A influences TLR4 signaling and cytokine production , researchers should investigate whether TMEM150B similarly affects immune pathways or influences other signaling cascades in reproductive tissues.

• Subcellular localization studies: Co-localization with organelle markers can provide insights into potential functions. For transmembrane proteins, localization to specific membrane compartments (plasma membrane, endoplasmic reticulum, Golgi, endosomes) provides functional clues.

• Interspecies conservation analysis: Examining conservation of TMEM150B across species can identify critical domains and potential functional motifs.

When designing these integrated approaches, researchers should consider evidence from related family members. For example, TMEM150A's role in regulating cytokine production suggests potential roles for TMEM150B in signaling processes that may not be immediately apparent in standard knockout phenotyping.

What emerging technologies may enhance future research on TMEM150B function and expression?

Several cutting-edge technologies hold promise for advancing TMEM150B research:

• Single-cell multi-omics: Integrating single-cell transcriptomics, proteomics, and epigenomics can reveal cell type-specific expression patterns and regulatory mechanisms controlling TMEM150B expression.

• CRISPR screening: Genome-wide or targeted CRISPR screens in TMEM150B-expressing cells can identify genetic interactions and functional pathways. CRISPRi/CRISPRa approaches allow for more nuanced modulation of expression.

• Advanced imaging techniques:

  • Super-resolution microscopy (STORM, PALM, SIM) for precise subcellular localization

  • Live-cell imaging with fluorescently tagged TMEM150B to track dynamics

  • Lattice light-sheet microscopy for 3D visualization in living cells

  • Expansion microscopy for enhanced resolution of membrane protein organization

• Organoid technologies: Testing TMEM150B function in 3D organoid cultures that better recapitulate in vivo tissue architecture, particularly for reproductive tissues.

• Protein structure determination: Cryo-EM or X-ray crystallography to determine TMEM150B structure, informing function and potential drug targeting.

• Spatial transcriptomics: Mapping TMEM150B expression within the context of intact tissues while preserving spatial information.

• Conditional and inducible knockout systems: Temporal and tissue-specific modulation of TMEM150B expression to bypass potential developmental compensation seen in constitutive knockouts.

• Humanized mouse models: For investigating human-specific aspects of TMEM150B function that may differ from rodent models, particularly relevant given the associations with human reproductive timing.

How does current research on TMEM150B relate to human reproductive health and disease?

While TMEM150B appears dispensable for female fertility in mice , several lines of evidence suggest potential relevance to human reproductive health:

Researchers investigating TMEM150B in clinical contexts should consider these gaps between mouse models and human genetic studies, potentially employing human cell-based systems or examining TMEM150B in the context of stressed or aging reproductive tissues.

What methodological approaches can researchers use to study TMEM150B in human samples?

For studying TMEM150B in human contexts, researchers can employ these methodological approaches:

• Human tissue immunohistochemistry:

  • Use validated TMEM150B antibodies on human ovarian tissues (with appropriate controls)

  • Compare expression across different stages of follicular development

  • Analyze expression patterns in normal versus pathological samples (e.g., POI patients)

• Human cell-based models:

  • Primary human granulosa cells or oocytes (limited availability)

  • Immortalized human ovarian cell lines

  • Human embryonic stem cell-derived models of germ cell development

  • Human ovarian organoids

• Clinical sample analysis:

  • RT-qPCR measurement of TMEM150B expression in granulosa cells from IVF patients

  • Correlation of expression levels with clinical parameters (maternal age, ovarian reserve markers, IVF outcomes)

  • Single-cell RNA-seq of human follicular cells to identify cell type-specific expression

• Genetic association validation:

  • Targeted sequencing of TMEM150B in POI patient cohorts

  • Functional analysis of identified variants using reporter assays

  • Analysis of SNPs in regulatory regions affecting TMEM150B expression

• CRISPR-edited human cell lines:

  • Generate TMEM150B knockouts in relevant human cell lines

  • Analyze effects on cellular processes and signaling pathways

  • Introduce specific variants identified in patient populations

When working with human samples, researchers must address ethical considerations and sample limitations, often necessitating complementary approaches using animal models and in vitro systems to build a comprehensive understanding of TMEM150B function in reproductive health.

What key questions remain unanswered about TMEM150B function and regulation?

Despite progress in characterizing TMEM150B, several critical questions remain:

• What is the molecular function of TMEM150B? While we know it's dispensable for fertility in mice, its actual cellular function remains unclear. Does it serve as a channel, receptor, scaffold, or have enzymatic activity?

• How does TMEM150B interact with other TMEM150 family members? Are there compensatory mechanisms that mask phenotypes in single knockout models? What is the degree of functional redundancy between family members?

• What explains the discrepancy between human genetic associations and mouse knockout phenotypes? Does TMEM150B have species-specific functions or is it only relevant under specific physiological conditions not replicated in laboratory settings?

• What is the subcellular localization and trafficking of TMEM150B? Understanding its precise membrane localization could provide functional insights.

• What are the upstream regulators and downstream effectors of TMEM150B? Identifying the signaling pathways TMEM150B participates in could reveal its broader biological role.

• What is the role of post-translational modifications in regulating TMEM150B function? The discrepancy between predicted and observed molecular weights suggests possible modifications with functional implications.

• Does TMEM150B function change during aging or under stress conditions? Its association with menopause timing suggests potential age-related functions not apparent in young animal models.

These questions represent promising areas for future research, requiring multidisciplinary approaches combining genetic, biochemical, cell biological, and physiological methods to fully elucidate TMEM150B biology.

How should researchers integrate findings from different model systems when studying TMEM150B?

To develop a comprehensive understanding of TMEM150B function, researchers should:

• Cross-validate findings across models: Compare results from knockout mice, cell lines, and human samples to identify consistent patterns versus species-specific effects.

• Consider developmental context: Assess whether TMEM150B functions differently during development versus adulthood using stage-specific approaches.

• Evaluate environmental and physiological stress: Test TMEM150B function under varied conditions beyond standard laboratory environments, including aging, oxidative stress, and metabolic challenges.

• Employ complementary approaches: Integrate genetic, biochemical, imaging, and physiological methods to build a multi-dimensional understanding.

• Address compensatory mechanisms: Use acute knockout/knockdown strategies alongside constitutive models to distinguish direct versus compensated phenotypes.

• Translate between basic and clinical research: Connect fundamental insights from model organisms with human genetic and clinical data.

• Collaborate across disciplines: Form research teams spanning reproductive biology, cell biology, genetics, and clinical medicine to address TMEM150B function comprehensively.