SignalSilence? p21 Waf1/Cip1 siRNA I

• 产品编号：CST-6456S      品牌：CST       原厂货号：6456S
• 产品分类：DNA和RNA纯化 > RNA干扰 > RNAi Oligos > siRNA
• 应用分类：

描述：

CST的SignalSilence® p21 Waf1/Cip1 siRNA (Human Specific)使得研究人员可以使用RNA干扰的方法特异性抑制p21 Waf1/Cip1的表达，RNA干扰是一种通过将双链RNA分子转入细胞从而选择性沉默基因表达的方法。CST的所有SignalSilence® siRNA产品都通过了严格的内部测试，并能够减少特定细胞系内该蛋白的表达。CST建议使用100 nM p21 Waf1/Cip1 siRNA转染48-72小时后裂解细胞。转染的具体步骤请参考转染试剂制造商提供的操作标准。使用过程中有任何问题请随时联系CST。肿瘤抑制蛋白p21 Waf1/Cip1能够充当细胞周期进程抑制剂。其功能与周期蛋白和周期蛋白依赖性激酶形成的异源三聚体存在化学计量关系。通过与CDK2复合体联合，它可以抑制激酶的活性和阻断G1/S进程(1)。然而，p21也可以增强CDK4或者CDEK6与周期蛋白-D形成的复合体的组装和活性(2)。p21的羧基末端区域能够充分结合并抑制PCNA，DNA聚合酶的一个亚基，而且可以协调细胞周期进程中DNA的复制(3)。基于紫外线损伤或者是在细胞周期中cdc2/cyclin B或CDK2/cyclin A活跃阶段，p53被磷酸化且通过p53-响应元件上调p21的表达(4)。泛素化和蛋白酶体降解能够下调p21的蛋白水平(5)。RNA干扰被用于沉默人内皮细胞p21 Cip1的表达，以阻断TNF-alpha介导的生长抑制(6)。

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. Basile, J. R. et al. (2003) Mol. Cancer Res. 1, 262-270.

原厂资料：

Description

SignalSilence® p21 Waf1/Cip1 siRNA (Human Specific) allows the researcher to specifically inhibit p21 Waf1/Cip1 expression using RNA interference, a method in which gene expression can be selectively silenced through the delivery of double stranded RNA molecules into the cell. All SignalSilence® siRNA products from Cell Signaling Technology are rigorously tested in-house and have been shown to reduce protein expression in specified cell lines

Directions for Use

CST recommends transfection with 100 nM p21 Waf1/Cip1 siRNA 48 hours prior to cell lysis. For transfection procedure, follow protocol provided by the transfection reagent manufacturer. Please feel free to contact CST with any questions on use.

Background

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 is 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). RNA interference has been used to silence p21 Cip1 expression in human endothelial cells, preventing TNF-alpha mediated growth inhibition (6).

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. Basile, J. R. et al. (2003) Mol. Cancer Res. 1, 262-270.

注意事项：

Storage: p21 Waf1/Cip1 siRNA is supplied
in RNase-free water. Aliquot and store at
–20°C.