Telomerase synthesizes tandem repeats of the sequence d(TTGGGG) onto input d(TTGGGG)n primer oligonucleotides (C. W. Greider and E. H. Blackburn, Cell 43:405-413). An intrinsic RNA component of the enzyme provides the template for d(TTGGGG)n repeat synthesis [C. W. Greider and E. H. Blackburn, Nature (London) 337:331-337, 1989; G.-L. Lu, J. D. Bradley, L. D. Attardi, and E. H. Blackburn, Nature (London) 344:126-132, 1990]. In a typical reaction, products greater than 2,000 nucleotides were synthesized in 60 min. Dilution and primer challenge experiments showed that these long products were synthesized processively. The apparent processivity was not due to a higher affinity of the enzyme for long d(TTGGGG) products over the shorter competitors. The degree of processivity was quantitated; telomerase synthesized approximately 520 nucleotides before half of the enzyme had dissociated. After dissociating, telomerase reinitiated d(TTGGGG)n synthesis on new primer oligonucleotides. The products from a telomerase reaction have a characteristic 6-nucleotide banding pattern (C. W. Greider and E. H. Blackburn, Cell 51:887-898, 1987). A strong pause in the reaction occurs after the addition of the first G in the sequence d(TTGGGG). Both the processivity and the banding pattern analysis imply that in the elongation mechanism there must be a translocation step after the 9 nucleotides of internal template RNA have been copied to the extreme 5' end.
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机译：端粒酶将序列d（TTGGGG）的串联重复序列合成到输入的d（TTGGGG）n引物寡核苷酸上（C. W. Greider和E. H. Blackburn，Cell 43：405-413）。酶的固有RNA成分为d（TTGGGG）n重复合成提供了模板[C. W.Greider和E.H.Blackburn，Nature（伦敦）337：331-337，1989;和G.-L. Lu，J.D.Bradley，L.D.Attardi和E.H.Blackburn，Nature（伦敦）344：126-132，1990]。在典型的反应中，在60分钟内合成了大于2,000个核苷酸的产物。稀释和引物激发实验表明，这些长产物是合成合成的。明显的合成能力不是由于酶对长d（TTGGGG）产品的竞争性高于较短的竞争者。进行性的程度被定量。在一半的酶解离之前，端粒酶合成了大约520个核苷酸。解离后，端粒酶在新的引物寡核苷酸上重新启动d（TTGGGG）n合成。来自端粒酶反应的产物具有特征性的6-核苷酸条带模式（C.W.Greider和E.H.Blackburn，Cell 51：887-898，1987）。在顺序d（TTGGGG）中添加第一个G后，反应会出现强烈的停顿。进行性和条带模式分析均暗示，在延伸机制中，必须将内部模板RNA的9个核苷酸复制到5'末端后才需要一个易位步骤。
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