Growth inhibition of glioblastoma cells by human Purα
Growth inhibition of glioblastoma cells by human Purα
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DOI：
10.1002/jcp.10029
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发表时间：
2001-12-01
影响因子：
5.6
通讯作者：
Khalili, K
中科院分区：
文献类型：
--
作者：
Darbinian, N;Gallia, GL;Khalili, K
Pura 是一种多功能 DNA 和 RNA 结合蛋白，参与转录和复制等多种生物事件。此外，该蛋白能够与多种细胞蛋白形成复合物，这些蛋白对细胞增殖很重要，包括转录因子 E2F-1。 Pur α 具有模块化结构，突出显示蛋白质中心区域交替出现三个碱性芳香族 I 类重复序列和两个酸性富含亮氨酸的 II 类重复序列。在此，我们证明 Pur α 的异位过度表达可抑制多种转化细胞和肿瘤细胞（包括人胶质母细胞瘤）的增殖。通过在集落形成测定中利用Pur α的各种缺失突变体，我们鉴定了跨越Pur α的第一II类重复序列（残基107-131）和第二I类重复序列（残基148-170）的区域，其参与Pur α的生长抑制作用。使用代表 Pur α 的残基 109-131 和 123-154 的合成肽与 HIV-1 Tat 的富含精氨酸的结构域融合的蛋白质转导实验的结果揭示了 Tat-Pur α 融合肽在 2 小时后的细胞内化和核外观，以及在治疗后长达 24 小时在细胞核中的检测。用 Tat-Pur α (109-131) 和 Tat-Pur α (123-154) 处理的胶质母细胞瘤细胞的增殖能力分别下降 41% 和 47%。总而言之，这些结果说明了 Pur α 在抑制胶质母细胞瘤细胞生长方面的功效，并为该蛋白质及其衍生物在阻止肿瘤细胞增殖方面的潜在用途提供了证据。 (C) 2001 Wiley-Liss, Inc.
Pura is a multifunctional DNA- and RNA-binding protein implicated in a variety of biological events including transcription and replication. Further, this protein has the ability to form a complex with several cellular proteins which are important for cell proliferation including the transcription factor, E2F-1. Pur alpha has a modular structure highlighted by alternating three basic aromatic class I and two acidic leucine-rich class II repeats in the central region of the protein. Here, we demonstrate that ectopic overexpression of Pur alpha suppresses proliferation of a variety of transformed and tumor cells including human glioblastoma. By utilizing various deletion mutants of Pur alpha in colony formation assay, we identified the region spanning the first class II repeat (residues 107-131) and the second class I repeat (residues 148-170) of Pur alpha which participate in growth inhibitory action of Pur alpha. Results from protein transduction experiments using the synthetic peptides representing residues 109-131 and 123-154 of Pur alpha in fusion with the arginine rich domain of HIV-1 Tat revealed cellular internalization and nuclear appearance of the Tat-Pur alpha fusion peptide after 2 h and its detection in nuclei up to 24 h after treatment. Glioblastoma cells treated with Tat-Pur alpha (109-131) and Tat-Pur alpha (123-154) exhibited 41 and 47% decrease, respectively, in proliferation. Altogether these results illustrate the efficacy of Pur alpha in suppressing glioblastoma cell growth and provide evidence for the potential use of this protein and its derivative(s) in blocking proliferation of tumor cells. (C) 2001 Wiley-Liss, Inc.