Telomestatin, a Potent Telomerase Inhibitor That Interacts Quite Specifically with the Human Telomeric Intramolecular G-Quadruplex

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• 作者：Mu-Yong Kim ; Hariprasad Vankayalapati ; Kazuo Shin-ya ; Konstanty Wierzba ; and Laurence H. Hurley
• 刊名：Journal of the American Chemical Society
• 出版年：2002
• 出版时间：March 13, 2002
• 年：2002
• 卷：124
• 期：10
• 页码：2098 - 2099
• 全文大小：95K
• 年卷期：v.124,no.10(March 13, 2002)
• ISSN：1520-5126

文摘

Telomestatin is a natural product isolated from Streptomyces anulatus 3533-SV4 and has been shown to be a very potent telomerase inhibitor. The structural similarity between telomestatin and a G-tetrad suggested to us that the telomerase inhibition might be due to its ability either to facilitate the formation of or trap out preformed G-quadruplex structures, and thereby sequester single-stranded d[T₂AG₃]_n primer molecules required for telomerase activity. Significantly, telomestatin appears to be a more potent inhibitor of telomerase (5 nM) than any of the previously described G-quadruplex-interactive molecules. In this communication we provide the first experimental evidence that telomestatin selectively facilitates the formation of or stabilizes intramolecular G-quadruplexes, in particular, that produced from the human telomeric sequence d[T₂AG₃]₄. A simulated annealing (SA) docking approach was used to study the binding interactions of telomestatin with the intramolecular antiparallel G-quadruplex structure. Each intramolecular G-quadruplex molecule was found to bind two telomestatin molecules (unpublished results). A 2:1 model for the telomestatin bound in the external stacking mode in an energy minimized complex with the human telomeric basket-type G-quadruplex was constructed. Our observation that a G-quadruplex-interactive molecule without significant groove interactions is able to reorient in a G-quadruplex structure proints to the importance of core interaction with an asymmetric G-quadruplex structure in producing selective binding. Furthermore, the G-quadruplex interactions of telomestatin are more selective for the intramolecular structure in contrast to other G-quadruplex-interactive agents, such as TMPyP4.