Telomerase-negative immortalized human cells contain a novel type of promyelocytic leukemia (PML) body.
Telomerase-negative immortalized human cells contain a novel type of promyelocytic leukemia (PML) body.
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发表时间：
1999-09
期刊：
影响因子：
11.2
通讯作者：
Thomas R. Yeager;A. Neumann;Anna Englezou;L. Huschtscha;J. R. Noble;R. Reddel
中科院分区：
文献类型：
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作者：
Thomas R. Yeager;A. Neumann;Anna Englezou;L. Huschtscha;J. R. Noble;R. Reddel
端粒酶阴性的永生化人类细胞通过一种称为端粒替代延长（ALT）的机制来维持其端粒。我们在此报道ALT细胞含有一种新型的早幼粒细胞白血病（PML）小体（ALT相关PML小体，APB）。 APB 是大型环形核结构，含有 PML 蛋白、端粒 DNA 以及端粒结合蛋白人端粒重复结合因子 1 和 2。免疫染色显示 APB 还含有复制因子 A、RAD51 和 RAD52，这些蛋白质参与 DNA 合成和重组。在永生化过程中，APB 的出现与 ALT 的激活完全相同。在 ALT 肿瘤和细胞系中发现了 APB，但在致命细胞株或端粒酶阳性细胞系或肿瘤中未发现。
Telomerase-negative immortalized human cells maintain their telomeres by a mechanism known as alternative lengthening of telomeres (ALT). We report here that ALT cells contain a novel promyelocytic leukemia (PML) body (ALT-associated PML body, APB). APBs are large donut-shaped nuclear structures containing PML protein, telomeric DNA, and the telomere binding proteins human telomere repeat binding factors 1 and 2. Immunostaining showed that APBs also contain replication factor A, RAD51, and RAD52, proteins involved in DNA synthesis and recombination. During immortalization, APBs appeared at exactly the same time as activation of ALT. APBs were found in ALT tumors and cell lines but not in mortal cell strains or in telomerase-positive cell lines or tumors.