BAF57/SMARCE1 Antibody (Rabbit mAb) [B6L12]

製品コード:F5650

印刷

生物学的記述

Specificity BAF57/SMARCE1 Antibody (Rabbit mAb) [B6L12] detects endogenous levels of total BAF57/SMARCE1 protein.
Background BAF57, encoded by the SMARCE1 gene, is a core subunit of mammalian SWI/SNF (BAF) ATP‑dependent chromatin remodeling complexes that act as master regulators of gene transcription by repositioning or destabilizing nucleosomes to modulate access of transcription factors to DNA. The protein contains an HMG‑box DNA‑binding domain that recognizes distorted or four‑way junction DNA and associates with nucleosomal and linker regions, positioning BAF57 as a modular interface that links chromatin architecture to sequence‑specific transcription factors and signaling inputs. Within SWI/SNF assemblies, BAF57 participates in gene regulatory programs controlling cell cycle progression, proliferation, and differentiation, and exerts tissue‑specific functions through selective incorporation into BAF complexes that respond to developmental and environmental cues. In breast cancer cells, BAF57 directly interacts with estrogen receptor alpha (ERα), using defined domains to bind the ERα hinge region and facilitating recruitment of SWI/SNF complexes to ERα target promoters, which enhances chromatin remodeling and transcription of estrogen‑responsive genes and supports estrogen‑stimulated proliferation. Disruption of BAF57 expression or function in these cells reduces expression of multiple endogenous ER target genes and blocks estrogen‑driven cell cycle progression, indicating that SMARCE1 is a critical chromatin‑associated cofactor that couples nuclear hormone receptor signaling to ATP‑dependent nucleosome remodeling. Beyond hormone signaling, SMARCE1 influences metastatic behavior of breast cancer cells through a pathway involving HIF1A and PTK2 (FAK): loss or reduction of SMARCE1 alters SWI/SNF occupancy and transcriptional control of HIF1A‑responsive genes and PTK2‑regulated adhesion and migration machinery, leading to changes in cell motility, invasion, and metastatic potential. The same study shows that modulation of SMARCE1 levels reprograms gene expression networks linked to hypoxia signaling, focal adhesion dynamics, and cytoskeletal organization, aligning BAF57 function with integration of microenvironmental stress, chromatin state, and invasive behavior in tumor cells. Developmental roles are evident in zebrafish models, where smarce1 mutants display defective endocardial morphogenesis and altered expression of cardiac transcription factors, consistent with BAF57‑containing SWI/SNF complexes directing tissue‑specific transcriptional programs that pattern organ formation and maintain lineage identity. At the structural level, BAF57 embeds its HMG‑box within a multidomain scaffold that participates in protein–protein interactions with other BAF subunits and transcriptional regulators, allowing assembly of distinct SWI/SNF variants and contributing to combinatorial subunit usage that underlies context‑dependent chromatin remodeling. Functionally, SMARCE1 sits at a nodal point where chromatin remodeling, nuclear receptor signaling, hypoxia‑responsive transcription, and developmental programs converge, so experimental design around this target often focuses on its role in assembling specific BAF complexes, recruiting them to regulatory loci, and altering accessibility and transcription factor occupancy rather than on catalytic activity per se. Germline and somatic alterations in SMARCE1 have been linked to tumor and non‑tumor pathologies: loss‑of‑function mutations are reported in clear cell meningioma and other contexts, supporting a role for BAF57 dosage in controlling chromatin‑based tumor suppressor pathways, while dysregulated or high expression in breast and endometrial cancers associates with more aggressive clinical and pathological features. In inflammation and neurodegeneration, aberrant BAF57 activity has been proposed as a biomarker and mechanistic contributor, reflecting its capacity to modulate transcriptional programs governing immune modulation, neuronal gene expression, and stress responses, with SWI/SNF complex composition and SMARCE1 status influencing disease‑relevant gene networks.

使用情報

Application WB, IP, IHC, IF, FCM Dilution
WB IP IHC IF FCM
1:1000 - 1:10000 1:10 - 1:100 1:250 - 1:500 1:250 - 1:500 1:10 - 1:100
Reactivity Human
Source Rabbit Monoclonal Antibody MW 47 kDa
Storage Buffer PBS, pH 7.2+50% Glycerol+0.05% BSA+0.01% NaN3
Storage
(from the date of receipt)
-20°C (avoid freeze-thaw cycles), 2 years
WB
Experimental Protocol:
 
Sample preparation
1. Tissue: Lyse the tissue sample by adding an appropriate volume of ice-cold RIPA/Nuclear Lysis Buffer (containing Protease Inhibitor Cocktail),and homogenize the tissue at a low temperature or lyse it by sonication on ice, then incubate on ice for 30 minutes.
2. Adherent cell: Aspirate the culture medium and wash the cells with ice-cold PBS twice. Lyse the cells by adding an appropriate volume of RIPA/Nuclear Lysis Buffer (containing Protease Inhibitor Cocktail) , sonicate to lyse the cells, and incubate on ice for 30 minutes.
3. Suspension cell: Transfer the culture medium to a pre-cooled centrifuge tube. Centrifuge and aspirate the supernatant. Wash the cells with ice-cold PBS twice. Lyse the cells by adding an appropriate volume of RIPA/Nuclear Lysis Buffer (containing Protease Inhibitor Cocktail) , sonicate to lyse the cells, and incubate on ice for 30 minutes.
4. Place the lysate into a pre-cooled microcentrifuge tube. Centrifuge at 4°C for 15 min. Collect the supernatant;
5. Remove a small volume of lysate to determine the protein concentration;
6. Combine the lysate with protein loading buffer. Boil 20 µL sample under 95-100°C for 5 min. Centrifuge for 5 min after cool down on ice.
 
Electrophoretic separation
1. According to the concentration of extracted protein, load appropriate amount of protein sample and marker onto SDS-PAGE gels for electrophoresis. Recommended separating gel (lower gel) concentration: 10%. Reference Table for Selecting SDS-PAGE Separation Gel Concentrations
2. Power up 80V for 30 minutes. Then the power supply is adjusted (110 V~150 V), the Marker is observed, and the electrophoresis can be stopped when the indicator band of the predyed protein Marker where the protein is located is properly separated. (Note that the current should not be too large when electrophoresis, too large current (more than 150 mA) will cause the temperature to rise, affecting the result of running glue. If high currents cannot be avoided, an ice bath can be used to cool the bath.)
 
Transfer membrane
1. Take out the converter, soak the clip and consumables in the pre-cooled converter;
2. Activate PVDF membrane with methanol for 1 min and rinse with transfer buffer;
3. Install it in the order of "black edge of clip - sponge - filter paper - filter paper - glue -PVDF membrane - filter paper - filter paper - sponge - white edge of clip";
4. The protein was electrotransferred to PVDF membrane. ( 0.45 µm PVDF membrane is recommended ) Reference Table for Selecting PVDF Membrane Pore Size Specifications
Recommended conditions for wet transfer: 200 mA, 120 min.
( Note that the transfer conditions can be adjusted according to the protein size. For high-molecular-weight proteins, a higher current and longer transfer time are recommended. However, ensure that the transfer tank remains at a low temperature to prevent gel melting.)
 
Block
1. After electrotransfer, wash the film with TBST at room temperature for 5 minutes;
2. Incubate the film in the blocking solution for 1 hour at room temperature;
3. Wash the film with TBST for 3 times, 5 minutes each time.
 
Antibody incubation
1. Use primary antibody dilution buffer to prepare the primary antibody working liquid (recommended dilution ratio for primary antibody 1:1000), gently shake and incubate with the film at 4°C overnight;
2. Wash the film with TBST 3 times, 5 minutes each time;
3. Add the secondary antibody to the blocking solution and incubate with the film gently at room temperature for 1 hour;
4. After incubation, wash the film with TBST 3 times for 5 minutes each time.
 
Antibody staining
1. Add the prepared ECL luminescent substrate (or select other color developing substrate according to the second antibody) and mix evenly;
2. Incubate with the film for 1 minute, remove excess substrate (keep the film moist), wrap with plastic film, and expose in the imaging system.
IHC
Experimental Protocol:
 
Deparaffinization/Rehydration
1. Deparaffinize/hydrate sections:
2. Incubate sections in three washes of xylene for 5 min each.
3. Incubate sections in two washes of 100% ethanol for 10 min each.
4. Incubate sections in two washes of 95% ethanol for 10 min each.
5. Wash sections two times in dH2O for 5 min each.
6.Antigen retrieval: For Citrate: Heat slides in a microwave submersed in 1X citrate unmasking solution until boiling is initiated; continue with 10 min at a sub-boiling temperature (95°-98°C). Cool slides on bench top for 30 min.
 
Staining
1. Wash sections in dH2O three times for 5 min each.
2. Incubate sections in 3% hydrogen peroxide for 10 min.
3. Wash sections in dH2O two times for 5 min each.
4. Wash sections in wash buffer for 5 min.
5. Block each section with 100–400 µl of blocking solution for 1 hr at room temperature.
6. Remove blocking solution and add 100–400 µl primary antibody diluent in to each section. Incubate overnight at 4°C.
7. Remove antibody solution and wash sections with wash buffer three times for 5 min each.
8. Cover section with 1–3 drops HRPas needed. Incubate in a humidified chamber for 30 min at room temperature.
9. Wash sections three times with wash buffer for 5 min each.
10. Add DAB Chromogen Concentrate to DAB Diluent and mix well before use.
11. Apply 100–400 µl DAB to each section and monitor closely. 1–10 min generally provides an acceptable staining intensity.
12. Immerse slides in dH2O.
13. If desired, counterstain sections with hematoxylin.
14. Wash sections in dH2O two times for 5 min each.
15. Dehydrate sections: Incubate sections in 95% ethanol two times for 10 sec each; Repeat in 100% ethanol, incubating sections two times for 10 sec each; Repeat in xylene, incubating sections two times for 10 sec each.
16. Mount sections with coverslips and mounting medium.
 
IF
Experimental Protocol:
 
Sample Preparation
1. Adherent Cells: Place a clean, sterile coverslip in a culture dish. Once the cells grow to near confluence as a monolayer, remove the coverslip for further use.
2. Suspension Cells: Seed the cells onto a clean, sterile slide coated with poly-L-lysine.
3. Frozen Sections: Allow the slide to thaw at room temperature. Wash it with pure water or PBS for 2 times, 3 minutes each time.
4. Paraffin Sections: Deparaffinization and rehydration. Wash the slide with pure water or PBS for 3 times, 3 minutes each time. Then perform antigen retrieval.
 
Fixation
1. Fix the cell coverslips/spots or tissue sections at room temperature using a fixative such as 4% paraformaldehyde (4% PFA) for 10-15 minutes.
2. Wash the sample with PBS for 3 times, 3 minutes each time.
 
Permeabilization
1.Add a detergent such as 0.1–0.3% Triton X-100 to the sample and incubate at room temperature for 10–20 minutes.
(Note: This step is only required for intracellular antigens. For antigens expressed on the cell membrane, this step is unnecessary.)
Wash the sample with PBS for 3 times, 3 minutes each time.
 
Blocking
Add blocking solution and incubate at room temperature for at least 1 hour. (Common blocking solutions include: serum from the same source as the secondary antibody, BSA, or goat serum.)
Note: Ensure the sample remains moist during and after the blocking step to prevent drying, which can lead to high background.
 
Immunofluorescence Staining (Day 1)
1. Remove the blocking solution and add the diluted primary antibody.
2. Incubate the sample in a humidified chamber at 4°C overnight.
 
Immunofluorescence Staining (Day 2)
1. Remove the primary antibody and wash with PBST for 3 times, 5 minutes each time.
2. Add the diluted fluorescent secondary antibody and incubate in the dark at 4°C for 1–2 hours.
3. Remove the secondary antibody and wash with PBST for 3 times, 5 minutes each time.
4. Add diluted DAPI and incubate at room temperature in the dark for 5–10 minutes.
5. Wash with PBST for 3 times, 5 minutes each time.
 
Mounting
1. Mount the sample with an anti-fade mounting medium.
2. Allow the slide to dry at room temperature overnight in the dark.
3. Store the slide in a slide storage box at 4°C, protected from light.
 

References

  • https://pubmed.ncbi.nlm.nih.gov/27495308/
  • https://pubmed.ncbi.nlm.nih.gov/16769725/

Application Data

WB

Validated by Selleck

  • F5650-wb.gif
    Lane 1: MCF7, Lane 2: HeLa, Lane 3: Jurkat, Lane 4: Raji