文章基本信息

标题：The telomerase RNA pseudoknot is critical for the stable assembly of a catalytically active ribonucleoprotein
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作者：David Gilley ; Elizabeth H. Blackburn
期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1999
卷号：96
期号：12
页码：6621-6625
DOI：10.1073/pnas.96.12.6621
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Telomerase is a ribonucleoprotein reverse transcriptase that synthesizes telomeric DNA. A pseudoknot structure is phylogenetically conserved within the RNA component of telomerase in all ciliated protozoans examined. Here, we report that disruptions of the pseudoknot base pairing within the telomerase RNA from Tetrahymena thermophila prevent the stable assembly in vivo of an active telomerase. Restoring the base-pairing potential of the pseudoknot by compensatory changes restores telomerase activity to essentially wild-type levels. Therefore, the pseudoknot topology rather than sequence is critical for an active telomerase. Furthermore, we show that disruption of the pseudoknot prevents the association of the RNA with the reverse transcriptase protein subunit of telomerase. Thus, we provide an example of a structural motif within the telomerase RNA that is required for telomerase function and identify the domain that is required for telomerase complex formation. Hence, we identify a biological role for a pseudoknot: promoting the stable assembly of a catalytically active ribonucleoprotein.