PSMA3 (D4Y9O) Rabbit mAb

• 产品编号：CST-12446S      品牌：CST       原厂货号：12446S
• 产品分类：抗体 > 一抗 > 蛋白特异性一抗
• 应用分类：

描述：

PSMA3 (D4Y9O) Rabbit mAb兔单抗识别内源性的总PSMA3蛋白。该抗体与20S蛋白酶体的其他 α 亚基无交叉反应性。该抗体与特定细胞系裂解物中未知的140 kDa 蛋白有交叉反应。此单克隆抗体通过合成与人PSMA3蛋白Arg100邻近氨基酸残基序列已知的肽段，免疫动物产生。26S蛋白酶体是一种高丰度，大小约2 MDa的复合物，它具有泛素蛋白酶体途径的蛋白水解臂。它主要由两种亚型复合物组成，19S调节颗粒(RP)和20S催化核心颗粒(CP)，在许多情况下RPs会覆盖CP的任一末端。CP由包含催化位点的2种堆积β-环组成，每一种β-环由7种亚基组成(β_1-7)，且两侧包含两个分别由七个亚基构成的α环 (α_1-7).。因此，20S CP 的结构为α_1-7β_1-7β_1-7α_1-7。RP包括了一个底部和一个盖子。部分底部由ATPases的六角环组成，功能为打开底物蛋白和打开α-亚基交错的N-末端片段的闸门，从而使得未折叠的底物进入催化部位。盖子主要起特异性识别泛素信号的作用(1)。除了19S帽子之外，其他的蛋白和复合物，例如蛋白酶体活化因子28 (PA28/11S)，与20S的筒状末端结合，从而促进闸门的开放和激活。此外，蛋白酶体相关的DUBs和E3s能够改变底物嵌合的多泛素链，这可能调节了它们对降解的敏感性(2)。

1. Finley, D. (2009) Annu Rev Biochem 78, 477-513.
2. Lee, M.J. et al. (2011) Mol Cell Proteomics 10, R110.003871.
3. Gerards, W.L. et al. (1998) J Mol Biol 275, 113-21.
4. Touitou, R. et al. (2001) EMBO J 20, 2367-75.
5. Sdek, P. et al. (2005) Mol Cell 20, 699-708.

原厂资料：

Homology

Species predicted to react based on 100% sequence homology: Dog, Pig, Horse

Specificity / Sensitivity

PSMA3 (D4Y9O) Rabbit mAb recognizes endogenous levels of total PSMA3 protein. This antibody does not cross-react with other α subunits of the 20S proteasome. This antibody cross-reacts with a 140 kDa protein of unknown identity in lysates from certain cell lines.

Source / Purification

Monoclonal antibody is produced by immunizing animals with a synthetic peptide corresponding to residues surrounding Arg100 of human PSMA3 protein.

Background

The 26S proteasome is a highly abundant, ~2 MDa complex that serves as the proteolytic arm of the ubiquitin-proteasome system. It consists largely of two sub-complexes, the 19S regulatory particle (RP) and the 20S catalytic core particle (CP); in many cases two RPs cap either end of a CP. The CP is made of two stacked β-rings that contain the catalytic sites, each of which is made of seven subunits (β_1-7), flanked on either side by two α-rings, which are also made of seven subunits each (α_1-7). Thus, the structure of the 20S CP is α_1-7β_1-7β_1-7α_1-7. The RP includes a base and a lid. The base, in part, is composed of a hexametric ring of ATPases that function to unfold the substrate and open the gate of the interlacing amino-terminal segments of the α-subunits, thus allowing entry of the unfolded substrate into the catalytic chamber. The lid is predominantly involved in specific recognition of the ubiquitin signal (1). In addition to the 19S cap, other proteins and complexes, such as proteasome activator 28 (PA28/11S), bind to the end of the 20S cylinder and activate it by facilitating opening of the gate. Furthermore, proteasome-associated DUBs and E3s can remodel substrate-anchored polyubiquitin chains, which may modulate their susceptibility to degradation (2).PSMA3 (HC8/α7) is an α subunit of the 20S proteasome. PSMA3 lacks any known proteolytic activity but may have an important role in the intiation of ring formation and 20S proteasome assembly (3). Research studies have demonstrated that PSMA3 serves as a receptor within the proteasome, recruiting substrates that are destined for degradation in a ubiquitination-independent manner (4,5).

1. Finley, D. (2009) Annu Rev Biochem 78, 477-513.
2. Lee, M.J. et al. (2011) Mol Cell Proteomics 10, R110.003871.
3. Gerards, W.L. et al. (1998) J Mol Biol 275, 113-21.
4. Touitou, R. et al. (2001) EMBO J 20, 2367-75.
5. Sdek, P. et al. (2005) Mol Cell 20, 699-708.

注意事项：

Storage: Supplied in 10 mM sodium HEPES (pH 7.5), 150
mM NaCl, 100 µg/ml BSA, 50% glycerol and less than 0.02%
sodium azide. Store at –20°C. Do not aliquot the antibody.