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7167C 1 Kit (96 assays) $489.00.0


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Product Includes Volume Solution Color
p21 Waf1/Cip1 Mouse mAb Coated Microwells 96 tests
p21 Waf1/Cip1 Rabbit Detection mAb 1 ea Green (Lyophilized)
Anti-rabbit IgG, HRP-linked Antibody (ELISA Formulated) 1 ea Red (Lyophilized)
Detection Antibody Diluent 11 ml Green
HRP Diluent 11 ml Red
TMB Substrate 7004 11 ml
STOP Solution 7002 11 ml
ELISA Wash Buffer (20X) 25 ml
ELISA Sample Diluent 25 ml Blue
Sealing Tape 1 ea
Cell Lysis Buffer (10X) 9803 15 ml

Product Description

CST's PathScan® Total p21 Waf1/Cip1 Sandwich ELISA Kit is a solid phase sandwich enzyme-linked immunosorbent assay (ELISA) that detects endogenous levels of total p21 Waf1/Cip1 protein. A p21 Waf1/Cip1 mouse mAb has been coated onto the microwells. After incubation with cell lysates, total p21 Waf1/Cip1 protein is captured by the coated antibody. Following extensive washing, a p21 Waf1/Cip1 antibody is added to detect the captured total p21 Waf1/Cip1 protein. Anti-rabbit IgG, HRP-linked Antibody is then used to recognize the bound detection antibody. HRP substrate, TMB, is added to develop color. The magnitude of absorbance for this developed color is proportional to the quantity of total p21 Waf1/Cip1 protein.

Antibodies in kit are custom formulations specific to kit.

Specificity / Sensitivity

CST's PathScan® Total p21 Waf1/Cip1 Sandwich ELISA Kit #7167 detects endogenous levels of total p21 Waf1/Cip1 protein. As shown in Figure 1, cell lysates from 293, HeLa, K562 and THP1 are analyzed using PathScan® Total p21 Waf1/Cip1 Sandwich ELISA Kit #7167. Measured levels of total p21 Waf1/Cip1 protein correlate with levels detected by Western blot analysis. In Figure 3, Western blot analysis of protein captured in the p21 Waf1/Cip1 antibody coated microwell shows a major band corresponding to the p21 Waf1/Cip1 protein.

This kit detects proteins from the indicated species, as determined through in-house testing, but may also detect homologous proteins from other species.

The tumor suppressor protein p21 Waf1/Cip1 acts as an inhibitor of cell cycle progression. It functions in stoichiometric relationships forming heterotrimeric complexes with cyclins and cyclin-dependent kinases. In association with CDK2 complexes, it serves to inhibit kinase activity and block progression through G1/S (1). However, p21 may also enhance assembly and activity in complexes of CDK4 or CDK6 and cyclin D (2). The carboxy-terminal region of p21 is sufficient to bind and inhibit PCNA, a subunit of DNA polymerase, and may coordinate DNA replication with cell cycle progression (3). Upon UV damage or during cell cycle stages when cdc2/cyclin B or CDK2/cyclin A are active, p53 is phosphorylated and upregulates p21 transcription via a p53-responsive element (4). Protein levels of p21 are downregulated through ubiquitination and proteasomal degradation (5).

1.  Pestell, R.G. et al. (1999) Endocrine Rev. 20, 501-534.

2.  Cheng, J. et al. (1999) EMBO J. 18, 1571-1583.

3.  Flores-Rozas, H. et al. (1994) Proc. Natl. Acad. Sci. USA 91, 8655-8659.

4.  Wang, Y. and Prives, C. (1995) Nature 376, 88-91.

5.  Sheaff, R.J. et al. (2000) Cell 5, 403-410.

6.  Pechnick, R.N. et al. (2008) Proc Natl Acad Sci U S A 105, 1358-63.

Entrez-Gene Id 1026
Swiss-Prot Acc. P38936

For Research Use Only. Not For Use In Diagnostic Procedures.
Cell Signaling Technology is a trademark of Cell Signaling Technology, Inc.
PathScan is a trademark of Cell Signaling Technology, Inc.

PathScan® Total p21 Waf1/Cip1 Sandwich ELISA Kit