What is Gamma H2AX?
Phosphorylation of the Ser-139 residue of the histone variant H2AX, forming γH2AX, is an early cellular response to the induction of DNA double-strand breaks. Detection of this phosphorylation event has emerged as a highly specific and sensitive molecular marker for monitoring DNA damage initiation and resolution.
How does Gamma H2AX work?
γH2AX, the phosphorylated form of H2AX, is involved in the steps leading to chromatin decondensation after DNA double-strand breaks. γH2AX does not, itself, cause chromatin decondensation, but within 30 seconds of ionizing radiation, RNF8 protein can be detected in association with γH2AX.
How do you calculate gamma H2AX foci?
Quantification of γH2AX foci can be performed either manually, by individually counting the number of foci present in each cell nucleus or automatically, by evaluating the total γH2AX immunofluorescence intensity emission per cell, using high throughput techniques, such as flow cytometry.
What does yh2ax stain?
Phospho-H2AX or γ-H2AX- is a marker of DNA double-stranded breaks and can therefore be used to monitor DNA repair after, for example, irradiation. In addition, positive staining for phospho-H2AX may indicate genomic instability and telomere dysfunction in tumour cells and tissues.
Where is H2AX found?
Histone H2AX is a histone variant found in almost all eukaryotes. It makes a central contribution to genome stability through its role in the signaling of DNA damage events and by acting as a foundation for the assembly of repair foci.
What are foci in cells?
A large and a small clear cell focus of cellular alteration. Clear cell foci are characterized by relatively clear cytoplasm or cytoplasm with just a hint of very pale eosinophilic staining and wispy strands of cytoplasm making the cytoplasmic vacuoles have an indistinct border.
What is the role of H2A Z?
The histone variant H2A. Z is involved in several processes such as transcriptional control, DNA repair, regulation of centromeric heterochromatin and, not surprisingly, is implicated in diseases such as cancer.
What type of protein is H2A?
Histone H2A
Histone H2A is one of the five main histone proteins involved in the structure of chromatin in eukaryotic cells. The other histone proteins are: H1, H2B, H3 and H4.
What is gamma-H2AX immunofluorescence?
Gamma-H2AX immunofluorescence for the detection of tissue-specific genotoxicity in vivo The phosphorylation of histone H2AX in Serine 139 (gamma-H2AX) marks regions of DNA double strand breaks and contributes to the recruitment of DNA repair factors to the site of DNA damage.
Can histone H2AX (gamma-H2AX) be used for genotoxicity assessment in vivo?
The phosphorylation of histone H2AX in Serine 139 (gamma-H2AX) marks regions of DNA double strand breaks and contributes to the recruitment of DNA repair factors to the site of DNA damage. Gamma-H2AX is used widely as DNA damage marker in vitro, but its use for genotoxicity assessment in vivo has not been extensively investigated.
Where is histone H2AX phosphorylated in DSB?
In response to DSB, the histone H2AX is phosphorylated at Serine 139 in a region of several megabase pairs forming discrete nuclear foci detectable by immunofluorescence microscopy.
What is the function of γ-H2AX?
The γ-H2AX interacts with hundreds of other proteins and protein complexes such as MDC1, MRN, 53BP1, and BRCA1/BARD1 to form foci in the region of DSBs 24, 25. The γ-H2AX foci have been shown to represent a good approximation of DNA DSBs and have been therefore established as a marker for DSBs 26, 27.