磷酸化的ALK(Tyr1604)抗体仅在Tyr1604(对应NPM-ALK上Tyr664)被磷酸化后才能检测到ALK的存在。本抗体与其它激活的酪氨酸激酶(包括EGFR)有交叉反应。Antibodies are purified by protein A and peptide affinity chromatography 多克隆抗体通过用合成磷酸化多肽免疫动物得到,该多肽是根据人的ALK蛋白Tyr1604附近的氨基酸序列合成的。抗体经过protein A和亲和色谱纯化。间变性淋巴瘤激酶(ALK)是多效生长因子(PTN)的酪氨酸激酶受体,它是大脑胚胎发育过程中的生长因子(1-3)。 在表达ALK的细胞中,PTN诱导ALK及其下游效应因子IRS-1, Shc, PLCγ, 和PI3K激酶发生磷酸化(1)。ALK最初是从易位突变产生的NPM-ALK融合蛋白而被发现的(4)。NPM-ALK融合蛋白是一个组成性活化,有原癌基因活性的间变性淋巴瘤相关酪氨酸激酶(4)。 由NPM-ALK介导的PLCγ的活化可能对有丝分裂活性起到关键作用,并且可能对间变性淋巴瘤的发病过程很重要(5)。另一个完全不同的ALK原癌融合蛋白在非小细胞肺癌细胞株中被报道,该蛋白融合了ALK与EML4,其相应融合转录产物在一些肺腺癌中也有表达。在EML4-ALK融合蛋白中,微管相关蛋白EML4的短氨基末端区域和ALK的激酶活性区域融合在一起(6,7)。NPM-ALK蛋白上Tyr664(对应全长ALK上Tyr1604)的磷酸化对于其和PLCgamma相互作用是必须的(5)。该酪氨酸位点的定点突变会导致NPM-ALK失去原癌基因活性(5)。
Phospho-ALK (Tyr1604) Antibody detects ALK only when phosphorylated at Tyr1604 (equivalent to Tyr664 of NPM-ALK). This antibody may cross-react with other activated protein tyrosine kinases including EGFR
Source / Purification
Polyclonal antibodies are produced by immunizing animals with a synthetic phosphopeptide corresponding to residues surrounding Tyr1604 of human ALK.
Background
Anaplastic lymphoma kinase (ALK) is a tyrosine kinase receptor for pleiotrophin (PTN), a growth factor involved in embryonic brain development (1-3). In ALK-expressing cells, PTN induces phosphorylation of both ALK and the downstream effectors IRS-1, Shc, PLCγ, and PI3 kinase (1). ALK was originally discovered as an NPM (nucleophosmin)-ALK fusion protein produced by a translocation (4). The NPM-ALK fusion protein is a constitutively active, oncogenic tyrosine kinase associated with anaplastic lymphoma (4). Activation of PLCγ by NPM-ALK has been suggested to be a crucial step for its mitogenic activity and may be important in the pathogenesis of anaplastic lymphomas (5). A distinct ALK oncogenic fusion protein involving ALK and EML4 has been described from a non-small cell lung cancer cell line, with corresponding fusion transcripts present in some cases of lung adenocarcinoma. The short, amino-terminal region of the microtubule-associated protein EML4 is fused to the kinase domain of ALK (6,7).
Phosphorylated Tyr664 of NPM-ALK (equivalent to Tyr1604 of full length ALK) is required for the interaction with PLCgamma (5). Site-directed mutagenesis of this tyrosine residue results in the loss of oncogenic activity of NPM-ALK (5).