GOLT1A Antibody

What is GOLT1A and what cellular processes does it regulate?

GOLT1A (Golgi Transport 1A) is a transmembrane protein involved in the fusion of ER-derived transport vesicles with the Golgi complex . It is localized primarily to the Golgi apparatus membrane, endoplasmic reticulum, and nuclear envelope . Gene ontology annotations suggest it may possess lipase activity, though its precise molecular function continues to be elucidated . GOLT1A belongs to the GOT1 family of proteins and has an important paralog, GOLT1B, which shares similar functions in vesicle trafficking .

What applications are GOLT1A antibodies most commonly used for in research?

Based on the available literature, GOLT1A antibodies are primarily used for:

Most commercially available GOLT1A antibodies are polyclonal and raised in rabbits, with demonstrated reactivity against human and mouse GOLT1A proteins .

How should GOLT1A antibodies be validated for experimental use?

For proper validation of GOLT1A antibodies:

• Specificity testing: Perform western blots comparing wildtype versus GOLT1A knockdown samples

• Cross-reactivity assessment: Test against recombinant GOLT1A and closely related family members (particularly GOLT1B)

• Application-specific validation: Different applications (WB, IHC, IF) require separate validation protocols

• Subcellular localization confirmation: Colocalization studies with known Golgi markers (e.g., GM130) should show expected Golgi membrane localization pattern

• Blocking peptide controls: Use GOLT1A blocking peptides to confirm signal specificity

When using antibodies for quantitative analyses, standard curves with recombinant GOLT1A protein are essential for accurate measurements.

How is GOLT1A expression linked to breast cancer outcomes?

Research has identified significant correlations between GOLT1A expression and breast cancer progression:

• GOLT1A knockdown has been shown to restore tamoxifen resistance in breast cancer models

• Low GOLT1A expression levels correlate with better survival outcomes in breast cancer patients

• GOLT1A expression is significantly associated with tumor microenvironment (TME) scores and immune-related signatures

Specifically, a study published in Frontiers in Oncology revealed that GOLT1A expression was positively correlated with the infiltration of several immune cell types in breast cancer, including:

• Macrophages (particularly M0 and M2 subtypes)

• Regulatory T cells

• Neutrophils

• Dendritic cells

The same study found GOLT1A expression was negatively correlated with:

• CD8+ T cells

• CD4+ T cells

• Natural killer (NK) cells

What methodologies are recommended for studying GOLT1A in cancer tissue samples?

For investigating GOLT1A in cancer tissues, researchers should consider:

• Multiplex immunohistochemistry approach:

  • Co-staining GOLT1A with immune cell markers to validate correlations with specific immune cell populations

  • Using serial sections to assess spatial relationships between GOLT1A expression and immune infiltration

• Quantitative analysis:

  • Digital image analysis for precise quantification of GOLT1A expression levels

  • Normalization against housekeeping proteins

• Correlation with clinical data:

  • Kaplan-Meier survival analysis stratified by GOLT1A expression levels

  • Multivariate analysis to assess independence from other prognostic factors

• Validation across multiple cohorts:

  • Use of publicly available databases (TIMER, CIBERSORT) to validate findings

  • Meta-analysis across independent patient cohorts

• Functional validation:

  • GOLT1A knockdown or overexpression in cell line models

  • Assessment of tamoxifen sensitivity changes following GOLT1A modulation

How does GOLT1A influence immune cell infiltration in tumors?

Research indicates GOLT1A plays a complex role in regulating immune cell infiltration in breast cancer:

The expression of GOLT1A has been significantly positively correlated with infiltration of:

• Macrophages (especially M0 and M2 types)

• Induced regulatory T cells (iTreg)

• Natural regulatory T cells (nTreg)

• Dendritic cells

• Central memory T cells

• Type 1 helper T cells

Conversely, GOLT1A expression showed significant negative correlation with:

• CD4+ T cells

• Gamma delta T cells (Tγδ)

• Helper follicular T cells (TFH)

• Mucosal associated invariant T cells (MAIT)

• Natural killer T cells (NKT)

• Natural killer (NK) cells

• CD8+ T cells

GOLT1A expression also correlates positively with immune checkpoint molecules:

• CD274 (PD-L1)

• TIGIT

• CTLA4

These findings suggest GOLT1A could potentially influence tumor progression by modulating the immune microenvironment, making it a possible target for immunotherapy research.

What techniques are recommended for investigating GOLT1A's role in immune regulation?

For comprehensive investigation of GOLT1A's role in immune regulation:

• Single-cell RNA sequencing:

  • Profile immune cell populations in GOLT1A-high versus GOLT1A-low tumors

  • Identify cell-specific transcriptional programs affected by GOLT1A expression

• Co-immunoprecipitation assays:

  • Identify potential binding partners of GOLT1A in immune cells

  • Elucidate signaling pathways affected by GOLT1A expression

• Immune cell functional assays:

  • T cell proliferation and cytotoxicity assays in the presence of GOLT1A-expressing cells

  • Macrophage polarization studies with GOLT1A modulation

• In vivo tumor models:

  • GOLT1A knockdown/overexpression in syngeneic mouse models

  • Immune depletion studies to determine which immune cell populations mediate GOLT1A effects

  • Flow cytometry analysis of tumor-infiltrating lymphocytes

• Cytokine profiling:

  • Multiplex analysis of cytokine production in GOLT1A-modified systems

  • Correlation of cytokine profiles with immune cell infiltration patterns

How might targeting GOLT1A influence response to cancer immunotherapy?

Given GOLT1A's correlation with immune checkpoint molecules and its association with immunosuppressive cell types, targeting GOLT1A may have implications for immunotherapy:

• Potential synergy with checkpoint inhibitors:

  • GOLT1A expression correlates positively with checkpoint molecules CD274 (PD-L1), TIGIT, and CTLA4

  • GOLT1A knockdown could potentially enhance response to anti-PD-1/PD-L1 or anti-CTLA4 therapies

• Modulation of immunosuppressive tumor microenvironment:

  • GOLT1A correlates with M2 macrophages and regulatory T cells, which typically suppress anti-tumor immunity

  • Targeting GOLT1A might reduce immunosuppressive cell infiltration

• Impact on antigen presentation:

  • As a vesicular transport protein, GOLT1A may influence antigen processing and presentation

  • Modulating GOLT1A could potentially enhance tumor antigen recognition

• Combination therapy approaches:

  • GOLT1A knockdown restored tamoxifen resistance in breast cancer , suggesting potential for combination with endocrine therapy

  • Dual targeting of GOLT1A and immune checkpoints may provide synergistic effects

Researchers should consider investigating GOLT1A inhibition in combination with current immunotherapeutic approaches, particularly in breast cancer models where GOLT1A's roles have been most clearly defined.

What methodological approaches can be used to develop GOLT1A-targeting therapeutics?

For researchers interested in developing GOLT1A-targeting approaches:

• Target validation strategies:

  • CRISPR-Cas9 knockout studies in relevant cancer models

  • Inducible shRNA systems for temporal control of GOLT1A expression

  • Patient-derived xenografts with variable GOLT1A expression levels

• Small molecule screening:

  • High-throughput screening assays targeting GOLT1A function

  • Structure-based drug design (if crystal structure available)

  • Phenotypic screens using immune cell infiltration as readout

• Antibody-based approaches:

  • Development of function-blocking GOLT1A antibodies

  • Antibody-drug conjugates targeting GOLT1A-expressing cells

  • Bispecific antibodies linking GOLT1A with immune effector cells

• Delivery system considerations:

  • Lipid nanoparticles for siRNA/shRNA delivery

  • Tumor-targeting peptides for enhanced specificity

  • Cancer cell-specific promoters for gene therapy approaches

• Biomarker development:

  • Identification of patient populations most likely to benefit from GOLT1A targeting

  • Development of companion diagnostics for GOLT1A expression levels

How does GOLT1A influence antibody production in expression systems?

Research has identified GOLT1A as a potential modulator of antibody production in expression systems:

• In Saccharomyces cerevisiae studies, overexpression of GOT1 (yeast homolog of GOLT1A) increased antibody titers by approximately 1.4-fold

• When co-expressed with other genes involved in secretory pathway function (IRE1, PSA1, HUT1), GOT1 contributed to synergistic enhancement of antibody production:

  • GOT1 + IRE1: 2.9-fold increase

  • GOT1 + PSA1 + IRE1: 6.4-fold increase in per-cell productivity

• The enhancement appears specific to complex proteins like antibodies, as GOT1 overexpression did not improve secretion of simpler proteins like acid phosphatase

• GOT1's role in vesicular transport between ER and Golgi likely helps alleviate secretory bottlenecks that occur during expression of complex multi-domain proteins

These findings suggest GOLT1A/GOT1 modulation could be valuable for biotechnology applications requiring high-yield production of complex proteins.

What are recommended protocols for investigating GOLT1A's role in protein secretion pathways?

For researchers investigating GOLT1A's role in secretory pathways:

• Pulse-chase experiments:

  • Metabolic labeling of newly synthesized proteins

  • Tracking secretion kinetics in GOLT1A-modified versus control cells

  • Quantification of intracellular retention versus secreted fractions

• Secretory organelle imaging:

  • Live-cell imaging with fluorescent markers for ER, ERGIC, and Golgi

  • Assessment of morphological changes upon GOLT1A modulation

  • Super-resolution microscopy to visualize vesicular transport intermediates

• Cargo-specific trafficking assays:

  • RUSH system (Retention Using Selective Hooks) to synchronize cargo release

  • VSVG-GFP temperature-sensitive trafficking assay

  • Antibody fragment secretion in reporter systems

• Co-expression strategies:

  • Systematic co-expression with UPR components (IRE1, XBP1)

  • Combination with other trafficking modulators (PSA1, HUT1)

  • Dosage optimization through titrable expression systems

• Proteomics approaches:

  • Proximity labeling (BioID, APEX) to identify GOLT1A interaction partners

  • Comparative secretome analysis in GOLT1A-modified cells

  • Glycoproteomics to assess effects on protein glycosylation

The protocols should include proper controls and statistical analysis to accurately quantify GOLT1A's effects on specific cargo proteins and distinguish general versus cargo-specific effects.

What are common technical challenges when working with GOLT1A antibodies?

Researchers should be aware of several technical challenges when using GOLT1A antibodies:

• Protein size and detection issues:

  • GOLT1A is a small protein (~15 kDa observed molecular weight)

  • May require special gel systems for effective resolution

  • Can be difficult to distinguish from non-specific bands

• Subcellular localization challenges:

  • As a membrane protein spanning the Golgi apparatus, GOLT1A requires proper membrane extraction protocols

  • May require special fixation methods to preserve Golgi morphology in microscopy

• Cross-reactivity concerns:

  • Potential cross-reactivity with GOLT1B paralog

  • Some commercial antibodies show cross-reactivity with GOT1 (aspartate aminotransferase)

  • Validation with appropriate controls is essential

• Sample preparation considerations:

  • GOLT1A antibody vials may occasionally have liquid entrapped in the cap during shipment

  • Brief centrifugation recommended before use

  • Proper aliquoting and storage at -20°C recommended to avoid freeze-thaw cycles

• Application-specific optimization:

  • Different dilutions required for different applications (WB: 1:1000-3000; IHC: 1:100-1:300; ELISA: 1:5000)

  • May require optimization of blocking conditions to reduce background

What controls and validation steps are essential for GOLT1A antibody-based experiments?

For rigorous GOLT1A research, the following controls and validation steps are recommended:

• Positive and negative controls:

  • Use of cell lines with known GOLT1A expression levels

  • GOLT1A knockdown/knockout controls

  • Recombinant GOLT1A protein as positive control

• Blocking peptide verification:

  • Pre-incubation of antibody with GOLT1A blocking peptide should abolish specific signal

  • Peptide competition assays to confirm epitope specificity

• Multiple antibody validation:

  • Use of antibodies targeting different epitopes of GOLT1A

  • Comparison of monoclonal versus polyclonal antibodies when available

• Cross-species validation:

  • Testing antibody reactivity across relevant species (human, mouse, rat)

  • Sequence alignment to predict cross-reactivity

• Application-specific controls:

  • For IHC: Include isotype controls and tissue with known expression patterns

  • For WB: Include molecular weight markers and loading controls

  • For IF: Include secondary-only controls and counterstains

• Reproducibility verification:

  • Independent replication with different antibody lots

  • Testing across multiple experimental conditions

  • Quantitative assessment of signal-to-noise ratio