Bcat1 Antibody

What is BCAT1 and what cellular functions does it perform?

BCAT1 (branched chain aminotransferase 1, cytosolic) is a cytosolic enzyme responsible for the reversible transamination of branched-chain amino acids (BCAAs) - leucine, isoleucine, and valine. It catalyzes the transformation of these essential BCAAs, which largely escape first-pass liver catabolism and remain available to peripheral organs. This metabolism provides an important mechanism by which nitrogen moves throughout the body for the synthesis of nonessential amino acids . BCAT1 has a calculated molecular weight of 36 kDa (320 amino acids), though its observed molecular weight in experimental conditions typically appears as 43-45 kDa on Western blots .

What applications can BCAT1 antibodies be used for in laboratory research?

BCAT1 antibodies have been validated for multiple research applications with specific recommended protocols:

The antibody 13640-1-AP specifically has been cited in 27 publications for WB, 11 for IHC, 6 for IF, and 1 for IP applications, demonstrating its reliability across multiple experimental contexts .

How should BCAT1 antibody samples be properly stored and handled?

For optimal performance and longevity of BCAT1 antibodies, follow these evidence-based storage recommendations:

• Store at -20°C where the antibody remains stable for one year after shipment

• The antibody is supplied in PBS buffer with 0.02% sodium azide and 50% glycerol at pH 7.3

• Aliquoting is unnecessary for -20°C storage

• Note that 20μl sizes contain 0.1% BSA which may affect some sensitive applications

• Avoid repeated freeze-thaw cycles which can decrease antibody activity and increase background signal

What antigen retrieval methods are recommended for BCAT1 immunohistochemistry?

For optimal antigen retrieval in IHC applications with BCAT1 antibody:

• Primary recommendation: Use TE buffer pH 9.0 for antigen retrieval

• Alternative approach: Antigen retrieval may also be performed with citrate buffer pH 6.0

• For mouse brain tissue and human stomach cancer tissue (where positive IHC has been validated), optimize retrieval time based on tissue section thickness (typically 5-20 minutes)

• Always perform antibody titration within your specific testing system as signal strength is sample-dependent

How is BCAT1 expression regulated by NOTCH1 signaling in T-cell acute lymphoblastic leukemia?

BCAT1 has been identified as a direct NOTCH1 target in T-cell acute lymphoblastic leukemia (T-ALL), with compelling evidence demonstrating this regulatory relationship:

• BCAT1 is overexpressed following NOTCH1-induced transformation of leukemic progenitors

• NOTCH1 directly controls BCAT1 expression by binding to the BCAT1 promoter

• Using retroviral models of T-ALL with NOTCH1 gain-of-function, mouse cells genetically deficient for Bcat1 showed significant defects in developing leukemia

• The increase in Bcat1 expression occurs early in T-ALL development and is unique among other enzymes involved in BCAA metabolism (e.g., Bcat2, Bckdha, and Bckdhb)

Comparison studies between normal thymocytes and leukemic cells have confirmed elevated Bcat1 expression at both transcript and protein levels in tumors induced through overexpression of activated NOTCH1 forms. This evidence suggests BCAT1 is essential for maintaining the oncogenic program driven by NOTCH1 mutation in T-ALL .

What metabolic changes occur following BCAT1 inhibition in cancer cells?

BCAT1 inhibition alters cellular metabolism with significant consequences for cancer cell function:

• Suppression of BCAT1 in glioma cell lines blocks the excretion of glutamate, which is critical for tumor cell proliferation and invasiveness

• In murine T-ALL cells, Bcat1 depletion or inhibition redirects leucine metabolism towards production of 3-hydroxy butyrate (3-HB), an endogenous histone deacetylase inhibitor

• This metabolic shift correlates with altered protein acetylation levels, particularly affecting histone and non-histone proteins involved in DNA damage response

• Gabapentin, a BCAT1 inhibitor, causes a concentration-dependent reduction in cell proliferation (up to 56%) as measured by 5-ethynyl-2′-deoxyuridine (EdU) incorporation assays

These metabolic changes illustrate how BCAT1 inhibition disrupts amino acid catabolism pathways critical for maintaining the cancer cell phenotype.

What experimental evidence links BCAT1 to glioblastoma progression?

Extensive experimental evidence supports BCAT1's role in glioblastoma progression:

• High BCAT1 expression is a characteristic feature of IDH wild-type gliomas, which can be used as a diagnostic marker

• BCAT1 expression is dependent on the concentration of α-ketoglutarate substrate in glioma cell lines

• Ectopic overexpression of mutant IDH1 in immortalized human astrocytes suppresses BCAT1 expression, providing a link between IDH1 function and BCAT1 regulation

• shRNA-mediated BCAT1 knockdown in glioma cell lines decreases proliferation by 20-70% and leads to G1 arrest with increased CDKN1B (p27KIP1) protein levels

In vivo studies using intracerebral transplantation of U-87MG cells into CD-1 nude mice demonstrated that BCAT1 knockdown significantly reduced tumor volume (p=0.0091). Four weeks post-transplantation, all six control mice exhibited neurologic symptoms, while only one of six mice with BCAT1 knockdown cells showed similar symptoms .

How does BCAT1 inhibition affect DNA damage response in cancer cells?

BCAT1 inhibition sensitizes cancer cells to DNA damage through multiple mechanisms:

• BCAT1-depleted cells show altered protein acetylation levels which correlate with pronounced sensitivity to DNA damaging agents

• The metabolic shift toward 3-hydroxy butyrate (3-HB) production following BCAT1 inhibition affects histone deacetylase activity, potentially altering chromatin accessibility

• In human NOTCH1-dependent leukemias, high expression levels of BCAT1 may predispose to worse prognosis and treatment resistance

• BCAT1 inhibition specifically synergizes with etoposide (a topoisomerase II inhibitor) to eliminate tumors in patient-derived xenograft models

These findings suggest BCAT1 inhibitors may have clinical potential in salvage protocols for refractory T-ALL and possibly other cancers where BCAT1 is overexpressed.

What methods are used to quantify and validate BCAT1 knockdown effects?

Researchers employ multiple complementary techniques to quantify and validate BCAT1 knockdown effects:

• Cell proliferation analysis:

  • EdU incorporation assays to measure actively proliferating cells

  • Cell counting at fixed timepoints after BCAT1 knockdown or inhibition

• Cell cycle analysis:

  • Flow cytometry to quantify cell distribution across G1, S, and G2/M phases

  • Western blotting for cell cycle regulators like CDKN1B (p27KIP1)

• Apoptosis measurements:

  • Sub-G1 fraction quantification

  • Annexin V and 7-AAD staining

  • Western blotting for cleaved PARP-1 and cleaved caspase 3

• In vivo validation:

  • Intracerebral transplantation in mice

  • Neurological symptom monitoring

  • H&E staining of brain sections

  • TUNEL assays to detect DNA fragmentation

  • Quantitative tumor volume measurements

How do researchers correlate BCAT1 expression with clinical outcomes in cancer patients?

To establish correlations between BCAT1 expression and patient outcomes, researchers employ:

• Tissue analysis techniques:

  • Immunohistochemical staining of patient tumor sections

  • Analysis of BCAT1 expression in relation to IDH1/IDH2 mutation status

  • Creation of independent cohorts for validation (e.g., analysis of 81 primary human gliomas in one study, with independent confirmation in a cohort of 210 gliomas)

• Data mining approaches:

  • Analysis of published RNA expression datasets

  • Integration of multiple independent cohorts to increase statistical power

  • Correlation of BCAT1 expression with prognostic indicators and survival

• Patient-derived models:

  • Patient-derived xenograft (PDX) models to test therapeutic interventions

  • Ex vivo culture of patient samples with BCAT1 inhibitors

  • Assessment of combinatorial approaches with standard-of-care therapies

What are the optimal Western blotting conditions for BCAT1 antibody?

For optimal Western blotting results with BCAT1 antibody, follow this methodological approach:

• Sample preparation:

  • Prepare total cell lysates using RIPA lysis buffer supplemented with phosphatase inhibitor cocktails and protease inhibitor tablets

  • Normalize protein concentration using the BCA method

• Electrophoresis and transfer:

  • Separate protein samples on 4-12% gradient Tris-glycine or 3-8% Tris-acetate SDS-PAGE gels

  • Transfer to PVDF membrane

• Antibody incubation:

  • Use BCAT1 antibody at 1:1000-1:4000 dilution (optimize for your specific sample)

  • Positive controls include Jurkat cells, HeLa cells, and Neuro-2a cells

  • Expected molecular weight: 43-45 kDa

• Detection:

  • Use appropriate secondary antibodies conjugated to HRP

  • Capture signals using chemiluminescence imaging systems such as BioRad ChemiDoc XRS Imager

What experimental approaches can validate BCAT1's role in cancer models?

To comprehensively validate BCAT1's role in cancer progression, researchers should implement:

• Genetic manipulation:

  • shRNA-mediated knockdown for transient suppression

  • CRISPR/Cas9 gene editing for complete knockout

  • Ectopic overexpression for rescue experiments

• Pharmacological inhibition:

  • Gabapentin treatment at varying concentrations (dose-response studies)

  • Assessment of inhibition specificity through metabolite analysis

• Functional assays:

  • Cell cycle analysis to quantify G1 arrest

  • Proliferation assays (EdU incorporation)

  • Apoptosis measurements

  • Invasion and migration assays

• In vivo validation:

  • Xenograft models with BCAT1-modified cells

  • Tumor volume quantification

  • Survival analysis

  • Combination therapy approaches

How might BCAT1 inhibitors be integrated into combination therapy approaches?

Based on current research findings, several promising avenues exist for integrating BCAT1 inhibitors into combination therapies:

• Synergy with DNA damaging agents:

  • BCAT1 inhibition specifically synergizes with etoposide in patient-derived xenograft models

  • The altered protein acetylation resulting from BCAT1 inhibition sensitizes cells to DNA damage

• Metabolic targeting combinations:

  • Combining BCAT1 inhibitors with other metabolic inhibitors may create synthetic lethality

  • Glutaminase inhibitors could potentially enhance the effects of BCAT1 inhibition by further restricting amino acid metabolism

• Biomarker-guided approaches:

  • High BCAT1 expression in IDH wild-type gliomas suggests potential for targeted therapy

  • NOTCH1-mutant T-ALL patients may particularly benefit from BCAT1 inhibition strategies

• Sequencing considerations:

  • Determining optimal sequencing of BCAT1 inhibitors with conventional therapies

  • Potential application in refractory disease contexts where standard approaches have failed

What challenges exist in developing specific BCAT1 inhibitors for research use?

Several challenges must be addressed in developing specific and effective BCAT1 inhibitors:

• Specificity concerns:

  • Distinguishing between BCAT1 and BCAT2 (mitochondrial isoform) activity

  • Minimizing off-target effects on other transaminases

• Delivery challenges:

  • For brain tumors, ensuring blood-brain barrier penetrance

  • Achieving sufficient intracellular concentrations

• Metabolic adaptation:

  • Anticipating and counteracting potential metabolic rewiring that may occur following BCAT1 inhibition

  • Identifying resistance mechanisms that might emerge

• Validation requirements:

  • Developing reliable pharmacodynamic markers to confirm target engagement

  • Establishing appropriate in vivo models that recapitulate human disease metabolism