B Cell Signaling Antibody Sampler Kit

• 产品编号：CST-9768S      品牌：Cell Signaling Technology       原厂货号：9768S
• 产品分类：抗体 > 一抗 > 复合抗体试剂盒
• 应用分类：

其它组分：

描述：

Syk 抗体检测内源Syk蛋白的总体水平。此抗体不与Syk/Zap-70酪氨酸激酶家族中的其它成员交叉反应。Phospho-Syk (Tyr525/526) (C87C1) Rabbit mAb 只能检测在 Tyr525/526 位点磷酸化的人源 Syk 或 Tyr519/520位点磷酸化的小鼠 Syk 。此抗体也能检测在人源Syk 在 Tyr526位点的单磷酸化或者 Tyr520 位点的小鼠Syk，但是不与其余酪氨酸磷酸化的酪氨酸激酶交叉反应。Lyn 抗体只能识别内源56 kDa 形式的 Lyn, 不能识别53 kDa形式的 Lyn 。 Phospho-Lyn (Tyr507) 抗体只能检测内源性在Tyr507位点磷酸化的Lyn总体水平。由于高度序列同源性，此抗体与phospho-Lck (Tyr505) 和 phospho-Src (Tyr527) 交叉反应。Btk 抗体内源Btk蛋白总体水平。Phospho-Btk (Tyr223) 抗体只能检测内源性在 Tyr223位点磷酸化的Btk。CD19 抗体检测内源CD19蛋白的总体水平。Phospho-CD19 (Tyr531) 抗体只能检测内源性在Tyr531位点磷酸化的CD19。此多克隆抗体是通过合成人源性 Syk 和 CD19 C-末端对应序列的未磷酸化肽段，对应 Lyn 的N-末端序列肽段，对应Btk的Tyr223周围肽段来免疫动物获得。Phospho-specific 多克隆抗体通过合成对应于 Lyn Tyr507周围的肽段，Btk Tyr223周围的肽段，CD19 Tyr531周围肽段来免疫动物而获得。兔源单克隆抗体是通过合成对应于人源性Syk的Tyr525/526的磷肽免疫动物而获得。B Cell Signaling Antibody Sampler Kit 为研究B细胞激活过程中关键并普遍存在的信号蛋白提供了经济的方法。试剂盒中提供的抗体能够检测每个目标蛋白的总体水平和磷酸化的蛋白。本试剂盒内含四次Western blots 所需的一抗和二抗。

yk作为酪氨酸蛋白激酶在造血细胞的胞内信号转导中起了重要的作用(1-3)。 Syk能够与免疫受体的酪氨酸介导的活性区域(ITAMs)中的胞质部分结合(4)。它能偶联激活了的免疫受体进行下游的信号转导而引起一系列的细胞响应，如细胞增殖，分化以及吞噬(4)。有证据显示Syk在无免疫反应的细胞中也有作用，Syk在人类的乳腺癌中是个潜在的肿瘤抑制因子(5)。 Tyrosines 525 位点和 526 位点位于 Syk 的激酶区域的活性环上。磷酸化人源的 Syk 的Tyr525/526位点(等同于小鼠 Syk的 Tyr519/520位点) 对 Syk 的功能有重要的影响(6)。

Lyn作为 Src 家族的一员，在造血细胞中高表达(7)。据报道两个酪氨酸残基对Src家族中的酪氨酸激酶调控发挥了及其重要的作用。催化区域 Tyr396位点的自磷酸化 (等同于 Src 的 Tyr416 位点 )，与酶活性有很大的关联。 Csk-介导的C-末端Tyr507位点的磷酸化 (等同于 Src 的 Tyr527 位点)能使酶失活。 酪氨酸激酶的磷酸化和 Lyn的激活与细胞表面受体BCR和 CD40 有关(8-10)。

Bruton's 酪氨酸激酶 (Btk)是细胞质激酶Btk/Tec家族的一员。 Btk在 B 细胞的发育过程中起了重要的作用 (11,12)。 B 细胞通过各种配体的激活总是伴随着PH 区域结合到磷脂酰肌醇-3,4,5-三磷酸化介导的Btk蛋白向膜定位 (13-15)。Btk定位于细胞膜后具有活性并瞬间磷酸化两个酪氨酸残基Tyr551 和 Tyr223。位于活性环上的 Tyr551 位点被Src家族酪氨酸激酶转磷酸化导致了SH3区域 Tyr223 位点的自磷酸化, 这对B 细胞的完全激活非常重要(16,17)。95 kDa的CD19蛋白作为共受体能够在B细胞中放大信号级联反应(18)。在B细胞的表面 ，CD19 与 CD21, CD81 和 Leu-13 共同发挥作用。 CD19 的细胞质尾巴有九个保守的酪氨酸残基通过偶联信号分子到受体上在CD19介导的功能中发挥了重要的作用(18)。BCR 或 CD19 结合后, CD19的Tyr531 和 Tyr500残基逐渐磷酸化，进而引起PI3激酶和Src家族的酪氨酸激酶偶联到CD19上，激活 PI3K 和 Src 信号通路 (19,20)。

原厂资料：

Specificity / Sensitivity

Syk Antibody detects endogenous levels of total Syk protein. It does not cross-react with other members of the Syk/Zap-70 tyrosine kinase family. Phospho-Syk (Tyr525/526) (C87C1) Rabbit mAb detects endogenous levels of Syk protein only when phosphorylated at Tyr525/526 of human Syk or Tyr519/520 of mouse Syk. It also detects Syk protein when singly phosphorylated at Tyr526 of human Syk or Tyr520 of mouse Syk, but does not cross-react with other tyrosine-phosphorylated protein tyrosine kinases. Lyn Antibody detects endogenous levels of the 56 kDa isoform of Lyn, but does not recognize the 53 kDa Lyn isoform. Phospho-Lyn (Tyr507) Antibody detects endogenous levels of Lyn only when phosphorylated at Tyr507. This antibody may cross-react with phospho-Lck (Tyr505) and phospho-Src (Tyr527) due to high sequence homology. Btk Antibody detects endogenous levels of total Btk protein. Phospho-Btk (Tyr223) Antibody detects endogenous levels of Btk only when phosphorylated at Tyr223. CD19 Antibody detects endogenous levels of total CD19 protein. Phospho-CD19 (Tyr531) Antibody detects endogenous levels of CD19 only when phosphorylated at Tyr531.

Source / Purification

Polyclonal antibodies are produced by immunizing animals with a synthetic nonphosphorylated peptide corresponding to the carboxy-terminal sequence of human Syk and human CD19, the amino-terminal sequence of human Lyn, and to residues surrounding Tyr223 of human Btk. Phospho-specific polyclonal antibodies are produced by immunizing animals with a synthetic phosphopeptide corresponding to residues surrounding Tyr507 of human Lyn, Tyr223 of human Btk, and Tyr531 of human CD19. Polyclonal antibodies are purified by protein A and peptide affinity chromatography. Rabbit monoclonal antibody is produced by immunizing animals with a synthetic phosphopeptide corresponding to residues surrounding Tyr525/526 of human Syk.

Description

The B Cell Signaling Antibody Sampler Kit provides an economical means to examine key signaling proteins commonly associated with B cell activation. The provided antibodies allow monitoring of both total protein levels and the phosphorylation state of each target. The kit includes enough primary and secondary antibody to perform four western mini-blot experiments.

Background

Syk is a protein tyrosine kinase that plays an important role in intracellular signal transduction in hematopoietic cells (1-3). Syk interacts with immunoreceptor tyrosine-based activation motifs (ITAMs) located in the cytoplasmic domains of immune receptors (4). It couples the activated immunoreceptors to downstream signaling events that mediate diverse cellular responses, including proliferation, differentiation, and phagocytosis (4). There is also evidence that Syk plays a role in nonimmune cells; Syk is a potential tumor suppressor in human breast carcinomas (5). Tyrosine 525 and 526 are located in the activation loop of the Syk kinase domain, and phosphorylation of Tyr525/526 of human Syk (equivalent to the Tyr519/520 of mouse Syk) is essential for Syk function (6). 
 
 Lyn, one of the Src family members, is predominantly expressed in hematopoietic cells (7). Two tyrosine residues have been reported to play a crucial role in the regulation of protein tyrosine kinases of the Src family. Autophosphorylation of Tyr396 (equivalent to Tyr416 of Src), located in the catalytic domain, correlates with enzyme activation. Csk-mediated phosphorylation of the carboxy-terminal Tyr507 (equivalent to Tyr527 of Src) inactivates the kinase. Tyrosine phosphorylation and activation of Lyn occurs upon association with cell surface receptors such as the B cell Ag receptor (BCR) and CD40 (8-10). 
 
 Bruton''''s tyrosine kinase (Btk) is a member of the Btk/Tec family of cytoplasmic tyrosine kinases. Btk plays an important role in B cell development (11,12). Activation of B cells by various ligands is accompanied by Btk membrane translocation mediated by its PH domain binding to phosphatidylinositol-3,4,5-trisphosphate (13-15). The membrane-located Btk is active and associated with transient phosphorylation of two tyrosine residues, Tyr551 and Tyr223. Tyr551 in the activation loop is transphosphorylated by the Src family tyrosine kinase, leading to autophosphorylation at Tyr223 within the SH3 domain, which is necessary for full activation (16,17). 
 
 CD19 is a 95 kDa coreceptor that amplifies the signaling cascade in B cells (18). On the B cell surface, CD19 associates with CD21, CD81, and Leu-13 to exert its function. The cytoplasmic tail of CD19 has nine conserved tyrosine residues playing critical roles in CD19-mediated function by coupling signaling molecules to the receptor (18). After BCR or CD19 ligation, Tyr531 and Tyr500 of CD19 are progressively phosphorylated. This phosphorylation enables the coupling of PI3 kinase and Src family tyrosine kinase to CD19 and activates the PI3K and Src signaling pathways (19,20).

注意事项：

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