Phospho-Histone H2A.X (Ser139), eFluor 660, clone: CR55T33, eBioscience™
Mouse Monoclonal Antibody
Manufacturer: Life Technologies LS50986542
Histones are relatively small proteins that contain a high proportion of positively charged amino acids, e.g., arginine and lysine. This positive charge allows histones to bind tightly to the negatively charged DNA. There are five basic types of histone molecules called H1, H2A, H2B, H3, and H4. Histones are abundantly present in virtually all eukaryotic cells.125 µg) per test. A test is defined as the amount (µg) of antibody that will stain a cell sample in a final volume of 100 µL. Cell number should be determined empirically but can range from 10^5 to 10^8 cells/test. The CR55T33 antibody has also been tested by immunocytochemistry of methanol-fixed human cells and can be used at less than or equal to 10 µg/mL. It is recommended that the antibody be carefully titrated for optimal performance in the assay of interest. Protocols: We recommend Protocol B: One-step protocol: intracellular (nuclear) proteins. Alternatively, Protocol C: Two-step protocol: Fixation/Methanol can also be used. Protocol A: Two-step protocol: intracellular (cytoplasmic) proteins cannot be used. All Protocols can be found in the "Staining intracellular Antigens for Flow Cytometry Protocol" located in the Best Protocols Section under the Resources tab online. eFluor® 660 is a replacement for Alexa Fluor® 647. eFluor® 660 emits at 659 nm and is excited with the red laser (633 nm). Please make sure that your instrument is capable of detecting this fluorochome. Excitation: 633-647 nm; Emission: 668 nm; Laser: Red Laser. Filtration: 0.2 μm post-manufacturing filtered. Histone H2A.X (H2AX) is a member of the histone H2A family which is one of the four core histones making up the nucleosome core particle. In eukaryotes, DNA double strand breaks (DSBs) have been shown to trigger the phosphorylation of serine 139 at the carboxy terminus of histone H2AX resulting in gamma-H2AX. The phosphorylation of H2AX can be detected by Western blotting or immunofluorescence, revealing the frequency of DSBs. The phosphatidylinositol 3-kinases have been implicated in H2AX phosphorylation, but it is unclear if ATM is the primary H2AX kinase or if other members of the family such as DNA-PK and ATR contribute in a similar manner. Structurally, H2A.x contains 143 amino acid residues. Histone H2A.X is considered a basal histone, being synthesized in G1 as well as in S-phase, and its mRNA contains polyA addition motifs and a polyA tail along with the conserved stem-loop and U7 binding sequences involved in the processing and stability of replication type histone mRNAs. There are two forms of Histone H2A.X mRNA, one about 1600 bases long and contains polyA; the other about 575 bases long, lacking polyA. The short form behaves as a replication type histone mRNA, while the longer behaves as a basal type histone mRNA. Histone H2A.X maps to the 11q23.2-q23.3 region of the human chromosome. Histone H2A.x contributes to histone-formation and therefore the structure of DNA. Histone H2A variant H2A.x specifically regulates the interaction of MDC1 (mediator of DNA damage checkpoint protein 1), a DNA repair protein to the sites of DNA damage.
|Phospho-Histone H2A.X (Ser139)|
|PBS with 0.1% gelatin, 0.2% BSA and 0.09% sodium azide; pH 7.2|
|Histone H2A type 2-C, H2A 2C, H2AFQ, HIST2H2AC, Histone H2A/q|
|Flow Cytometry, Immunocytochemistry, Immunofluorescence|
|4° C, store in dark, DO NOT FREEZE!|
For Research Use Only.