HnRNP A1 may interact simultaneously with telomeric DNA and the human telomerase RNA in vitro
HnRNP A1 may interact simultaneously with telomeric DNA and the human telomerase RNA in vitro
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DOI：
10.1093/nar/29.11.2268
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发表时间：
2001-06-01
影响因子：
14.9
通讯作者：
Chabot, B
中科院分区：
文献类型：
--
作者：
Fiset, S;Chabot, B
HnRNP A1蛋白和一种缩短的衍生物(UP1)促进哺乳动物细胞的端粒延长。为了支持A1在端粒生物发生中的直接作用，我们在体外证明了重组UP1蛋白与端粒DNA序列结合，并从细胞提取物中下调端粒酶活性。在这里，我们证明A1/UP1能直接与人端粒酶(HTR)的RNA成分相互作用，A1/UP1中包含RNA识别基序2(RRM2)的一部分足以与HTR的前208个核苷酸相互作用，鉴于A1/UP1中包含RRM1的部分足以与端粒DNA寡核苷酸结合，我们已经测试了A1/UP1是否能同时与两个核酸相互作用。通过层析实验，我们发现与HTR结合的A1/UP1可以与端粒DNA相互作用。值得注意的是，这些相互作用足够强大，足以经受住细胞提取液中的孵化。我们的结果表明hnRNP Al可能有助于将端粒酶招募到染色体末端。
The hnRNP A1 protein and a shortened derivative (UP1) promote telomere elongation in mammalian cells. In support of a direct role for Al in telomere biogenesis, we have shown that the recombinant UP1 protein binds to telomeric DNA sequences in vitro, and pulls down telomerase activity from a cell extract, Here we show that A1/UP1 can interact directly with the RNA component of human telomerase (hTR), A portion of A1/UP1 that contains RNA recognition motif 2 (RRM2) is sufficient for an interaction with the first 208 nt of hTR, Given that the portion of A1/UP1 that contains RRM1 is sufficient for binding to a telomeric DNA oligonucleotide, we have tested whether A1/UP1 can interact simultaneously with both nucleic acids. Using a chromatography assay, we find that A1/UP1 bound to hTR can interact with telomeric DNA. Notably, these interactions are sufficiently robust to withstand incubation in a cell extract. Our results suggest that hnRNP Al may help recruit telomerase to the ends of chromosomes.