Detection of human βV-tubulin expression in epithelial cancer cell lines by tubulin proteomics
Detection of human βV-tubulin expression in epithelial cancer cell lines by tubulin proteomics
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DOI：
10.1021/bi051004p
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发表时间：
2005-12-06
期刊：
影响因子：
2.9
通讯作者：
Horwitz, SB
中科院分区：
文献类型：
--
作者：
Verdier-Pinard, P;Shahabi, S;Horwitz, SB
微管蛋白是一种具有a和P亚基的异二聚体蛋白，在脊椎动物中分别由6个和7个不同的基因编码。每个微管蛋白同型可以通过其不同的c端序列来识别，然而，两组β -微管蛋白同型可以通过序列比对来区分；一种包括β I-、β II-、β IVa-和β ivb -微管蛋白，另一种包括β III-、β V-和β vi -微管蛋白。β iii -微管蛋白过表达与微管不稳定和紫杉醇抗性有关。最近的研究表明，小鼠β v -微管蛋白在CHO细胞中的过度表达导致微管严重紊乱，细胞依赖紫杉醇生长。小鼠和人类β V-tukllin序列表现出一些差异，比如它们各自的极端c端，这表明它们可能对微管稳定性有不同的影响，对药物的亲和力也不同。当高分辨率等电聚焦、凝胶内CNBr切割和质谱相结合时，我们首次在人细胞系中检测到v -微管蛋白，并发现它在上皮性卵巢癌细胞系Hey中高度表达。我们的数据证实，人类和啮齿动物的β v -微管蛋白是不同的，并且表明，无论物种如何。β III-和β v -微管蛋白可能在蛋白水平上以互补的模式表达。因此，应该系统地测定β III-和β v -微管蛋白的表达水平，以评估不同微管蛋白同型表达在肿瘤对靶向微管药物的反应中的作用。
Tubulin, the constitutive protein of microtububles, is a heterodimeric protein with an a and P Subunit, encoded in vertebrates by six and seven different genes, respectively. Each tubulin isotype can be identified by its divergent C-terminal sequence, Nevertheless, two groups of beta-tubulin isotypes can be distinguished by sequence alignment; one includes beta I-, beta II-, beta IVa-, and beta IVb-tubulin, and the other includes beta III-, beta V-, and beta VI-tubulin. beta III-tubulin overexpression has been associated with microtubule destabilization and resistance to Taxol. Recent data indicate that mouse beta V-tubulin overexpression in CHO cells results in profound rnicrotUbule disorganization and dependence of cells on Taxol for growth. Mouse and human beta V-tukllin sequences display several differences, such as their respective extreme C-terminus, suggesting that they may have different effects on microtubule stability and different affinities for drugs. When high-resolution isoelectric focusing, in-gel CNBr cleavage, and mass spectrometry were combined, we detected for the first time the V-tubulin protein in human cell lines and found that it was highly expressed in Hey, an epithelial ovarian cancer cell line. Our data confirm that human and rodent beta V-tubulins are distinct and indicate that, regardless of species. beta III- and beta V-tubulin may be expressed in a complementary pattern at the protein level. Therefore, both beta III- and beta V-tubulin expression levels should be systematically determined to assess the role of differential tubulin isotype expression in the response of tumors to drugs targeting microtubules.