| 货号 | 67625C |
| 反应种属 | Human |
| 应用 | ELISA |
| 目标/特异性 | PathScan® Phospho-Chk1 (Ser345) Sandwich ELISA Kit detects endogenous levels of Chk1 protein when phosphorylated at Ser345, as shown in Figure 1. |
| 供应商 | CST |
| 背景 | Chk1 kinase acts downstream of ATM/ATR kinase and plays an important role in DNA damage checkpoint control, embryonic development, and tumor suppression (1). Activation of Chk1 involves phosphorylation at Ser317 and Ser345 by ATM/ATR, followed by autophosphorylation of Ser296. Activation occurs in response to blocked DNA replication and certain forms of genotoxic stress (2). While phosphorylation at Ser345 serves to localize Chk1 to the nucleus following checkpoint activation (3), phosphorylation at Ser317 along with site-specific phosphorylation of PTEN allows for re-entry into the cell cycle following stalled DNA replication (4). Chk1 exerts its checkpoint mechanism on the cell cycle, in part, by regulating the cdc25 family of phosphatases. Chk1 phosphorylation of cdc25A targets it for proteolysis and inhibits its activity through 14-3-3 binding (5). Activated Chk1 can inactivate cdc25C via phosphorylation at Ser216, blocking the activation of cdc2 and transition into mitosis (6). Centrosomal Chk1 has been shown to phosphorylate cdc25B and inhibit its activation of CDK1-cyclin B1, thereby abrogating mitotic spindle formation and chromatin condensation (7). Furthermore, Chk1 plays a role in spindle checkpoint function through regulation of aurora B and BubR1 (8). Research studies have implicated Chk1 as a drug target for cancer therapy as its inhibition leads to cell death in many cancer cell lines (9). |
| 存放说明 | 4C |
| 参考文献 | Liu, Q. et al. (2000) Genes Dev 14, 1448-59. Zhao, H. and Piwnica-Worms, H. (2001) Mol Cell Biol 21, 4129-39. Jiang, K. et al. (2003) J Biol Chem 278, 25207-17. Martin, S.A. and Ouchi, T. (2008) Mol Cancer Ther 7, 2509-16. Chen, M.S. et al. (2003) Mol Cell Biol 23, 7488-97. Zeng, Y. et al. (1998) Nature 395, 507-10. Löffler, H. et al. (2006) Cell Cycle 5, 2543-7. Zachos, G. et al. (2007) Dev Cell 12, 247-60. Garber, K. (2005) J Natl Cancer Inst 97, 1026-8. |
Figure 2. The relationship between the protein concentration of lysates from untreated and UV-treated HeLa cells and the absorbance at 450 nm using the PathScan® Phospho-Chk1 (Ser345) Sandwich ELISA Kit is shown. HeLa cells (80-90% confluent) were treated with 100 mJ/cm2 UV with 1 hour recovery at 37ºC and then lysed with the lysis buffer. | |
Figure 1. Treatment of HeLa cells with UV stimulates phosphorylation of Chk1 at Ser345, as detected by the PathScan® Phospho-Chk1 (Ser345) Sandwich ELISA Kit, but does not affect the levels of total Chk1 detected by the PathScan® Total Chk1 Sandwich ELISA Kit #7872. The absorbance readings at 450 nm are shown in the top figure, while the corresponding western blots using Chk1 Antibody #2345 (left panel) or Phospho-Chk1 (Ser345) Rabbit mAb #2348 (right panel) are shown in the bottom figure. |
