XPA Antibody [H4H1]

製品コード:F1318

印刷

生物学的記述

Specificity XPA Antibody [H4H1] detects endogenous levels of total XPA protein.
Background The xeroderma pigmentosum group A (XPA) protein is a key scaffold in the nucleotide excision repair (NER) pathway, responsible for detecting and repairing bulky DNA lesions induced by UV light and chemical agents. XPA consists of 273 residues, with a central globular domain (residues 98–219) containing a C4-type zinc finger motif essential for its function. This domain is flanked by intrinsically disordered N- and C-terminal regions that mediate interactions with other NER proteins. The DNA-binding domain (DBD), formerly defined as residues 98–219, now extends to residue 239; this C-terminal extension forms an α-helix rich in basic residues, significantly enhancing DNA binding affinity. XPA preferentially recognizes single-strand/double-strand DNA junctions within the NER bubble, utilizing a basic cleft in its globular core and the C-terminal extension to achieve high-affinity, damage-specific DNA binding. This precise recognition facilitates the recruitment and spatial organization of additional repair factors, including RPA, ERCC1-XPF, and TFIIH, ensuring coordinated excision of damaged nucleotides. As an essential NER scaffold, XPA orchestrates both the initiation and progression of repair. Mutations in XPA lead to xeroderma pigmentosum, characterized by extreme UV sensitivity, skin cancer predisposition, and neurological abnormalities. XPA function is further regulated by ATR kinase-mediated phosphorylation at Ser196 in response to UV damage, which promotes its nuclear accumulation and enhances DNA repair activity.

使用情報

Application WB Dilution
WB
1:1000
Reactivity Human
Source Rabbit Monoclonal Antibody MW 40 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.
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) 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/Nuclear 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: 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, 60 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/26865925/
  • https://pubmed.ncbi.nlm.nih.gov/31925419/

Application Data