| 货号 | 9719S |
| 描述 | This Cell Signaling Technology antibody is conjugated to Alexa Fluor® 488 fluorescent dye and tested in-house for direct flow cytometry and immunofluorescent analysis in human cells. The antibody is expected to exhibit the same species cross-reactivity as the unconjugated Phospho-Histone H2A.X (Ser139) (20E3) Rabbit mAb #9718. |
| 反应种属 | Human/Mouse/Rat/Monkey |
| 来源宿主 | Rabbit |
| 应用 | F |
| 目标/特异性 | Phospho-Histone H2A.X (Ser139) (20E3) Rabbit mAb detects endogenous levels of H2A.X only when phosphorylated at serine 139. |
| 使用方法 | F(1:50) |
| 供应商 | CST |
| 标记 | Alexa Fluor 488 |
| 背景 | Histone H2A.X is a variant histone that represents approximately 10% of the total H2A histone proteins in normal human fibroblasts (1). H2A.X is required for checkpoint-mediated cell cycle arrest and DNA repair following double-stranded DNA breaks (1). DNA damage, caused by ionizing radiation, UV-light, or radiomimetic agents, results in rapid phosphorylation of H2A.X at Ser139 by PI3K-like kinases, including ATM, ATR, and DNA-PK (2,3). Within minutes following DNA damage, H2A.X is phosphorylated at Ser139 at sites of DNA damage (4). This very early event in the DNA-damage response is required for recruitment of a multitude of DNA-damage response proteins, including MDC1, NBS1, RAD50, MRE11, 53BP1, and BRCA1 (1). In addition to its role in DNA-damage repair, H2A.X is required for DNA fragmentation during apoptosis and is phosphorylated by various kinases in response to apoptotic signals. H2A.X is phosphorylated at Ser139 by DNA-PK in response to cell death receptor activation, c-Jun N-terminal Kinase (JNK1) in response to UV-A irradiation, and p38 MAPK in response to serum starvation (5-8). H2A.X is constitutively phosphorylated on Tyr142 in undamaged cells by WSTF (Williams-Beuren syndrome transcription factor) (9,10). Upon DNA damage, and concurrent with phosphorylation of Ser139, Tyr142 is dephosphorylated at sites of DNA damage by recruited EYA1 and EYA3 phosphatases (9). While phosphorylation at Ser139 facilitates the recruitment of DNA repair proteins and apoptotic proteins to sites of DNA damage, phosphorylation at Tyr142 appears to determine which set of proteins are recruited. Phosphorylation of H2A.X at Tyr142 inhibits the recruitment of DNA repair proteins and promotes binding of pro-apoptotic factors such as JNK1 (9). Mouse embryonic fibroblasts expressing only mutant H2A.X Y142F, which favors recruitment of DNA repair proteins over apoptotic proteins, show a reduced apoptotic response to ionizing radiation (9). Thus, it appears that the balance of H2A.X Tyr142 phosphorylation and dephosphorylation provides a switch mechanism to determine cell fate after DNA damage. |
| 存放说明 | 4C |
Flow cytometric analysis of Jurkat cells, untreated (green) or etoposide-treated (blue), using Phospho-Histone H2A.X (Ser139) (20E3) Rabbit mAb (Alexa Fluor® 488 Conjugate). 使用Phospho-Histone H2A.X (Ser139) (20E3) Rabbit mAb兔单抗 (Alexa Fluor® 488 Conjugate)标记，流式细胞仪分Jurkat细胞，细胞分为untreated (绿色)或etoposide-treated (蓝色)。 | |
Confocal immunofluorescent analysis of NIH/3T3 cells, untreated (left) or etoposide-treated (right), double-labeled with Phospho-Histone H2A.X (Ser139) (20E3) Rabbit mAb (Alexa Fluor® 488 Conjugate) (green) and beta-Tubulin Antibody #2146 (red). 使用Phospho-Histone H2A.X (Ser139) (20E3) Rabbit mAb 兔单抗(Alexa Fluor® 488 Conjugate) (绿色)和beta-Tubulin Antibody #2146 (红色)双标记，共聚焦免疫荧光分析NIH/3T3细胞，细胞分为untreated (左图)或etoposide-treated (右图)。 |
