BRCA1 Antibody [N12F20]

製品コード:F2632

印刷

生物学的記述

Specificity BRCA1 Antibody [N12F20] detects endogenous levels of total BRCA1 protein.
Background BRCA1 (Breast Cancer 1), encoded by the tumor suppressor gene mutated in hereditary breast and ovarian cancer syndrome, functions primarily as a scaffold coordinator of homologous recombination (HR) repair by recruiting PALB2, BRCA2, and RAD51 to double-strand breaks while repressing error-prone non-homologous end joining (NHEJ) during S and G2 phases, thereby maintaining genomic stability through cell cycle checkpoint activation and chromatin remodeling. BRCA1 (approximately 1863 amino acids) features an N-terminal RING domain with a Cys3HisCys4 motif (Cys24, Cys27, Cys37 catalytic for E2 ubiquitin ligase activity), central BRCT domains that contain phospho-serine binding pockets with conserved Ser988 and Ser1423 recognition sites, and multiple SQ/TQ phosphorylation sites (such as Ser1387 and Ser1524 targeted by ATM/ATR) that dynamically regulate protein interactions during the DNA damage response. BRCA1 orchestrates HR repair by ubiquitinylating histone H2A to recruit repair factors, phosphorylates CtIP to promote end resection and the creation of 3'-single-stranded DNA tails for RAD51 loading, activates the G2/M checkpoint via Chk1/2, and transcriptionally represses proliferation genes through p53 and BARD1 interactions. BRCA1 undergoes hyperphosphorylation during late G1/S (at Aurora A/CDK2 target sites Ser308 and Ser1497), peaking in M phase before partial dephosphorylation in early G1. Inactivating mutations (over 3000 identified) abolish HR capacity, causing accumulation of double-strand breaks, genomic instability, and tumorigenesis with a lifetime risk of breast cancer and ovarian cancer.

使用情報

Application WB, IP Dilution
WB IP
1:1000 1:50
Reactivity Human
Source Rabbit Monoclonal Antibody MW 220 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/NP-40 Lysis Buffer (containing Protease Inhibitor Cocktail),and homogenize the tissue at a low temperature.
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/NP-40 Lysis Buffer (containing Protease Inhibitor Cocktail) and put the sample on ice for 5 min.
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/NP-40 Lysis Buffer (containing Protease Inhibitor Cocktail) and put the sample on ice for 5 min.
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: 5%. 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: 250 mA, 180 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 5% skim milk powder 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.

References

  • https://pubmed.ncbi.nlm.nih.gov/27542409/
  • https://pubmed.ncbi.nlm.nih.gov/24451979/

Application Data