Prescott J, Blackburn E H
Department of Microbiology, University of California, San Francisco, San Francisco, California 94143-0414 USA.
Genes Dev. 1997 Nov 1;11(21):2790-800. doi: 10.1101/gad.11.21.2790.
The ribonucleoprotein (RNP) enzyme telomerase from Saccharomyces cerevisiae adds telomeric DNA to chromosomal ends in short increments both in vivo and in vitro. Whether or not telomerase functions as a multimer has not been addressed previously. Here we show, first, that following polymerization, the telomerase RNP remains stably bound to its telomeric oligonucleotide reaction product. We then exploit this finding and a previously reported mutant telomerase RNA to demonstrate that, unexpectedly, the S. cerevisiae telomerase complex contains at least two functionally interacting RNA molecules that both act as templates for DNA polymerization. Here, functional telomerase contains at least two active sites.
来自酿酒酵母的核糖核蛋白（RNP）酶端粒酶在体内和体外均以短片段的形式将端粒DNA添加到染色体末端。此前尚未探讨过端粒酶是否以多聚体形式发挥作用。在此，我们首先表明，聚合反应后，端粒酶RNP与其端粒寡核苷酸反应产物保持稳定结合。然后，我们利用这一发现以及先前报道的突变端粒酶RNA来证明，出乎意料的是，酿酒酵母端粒酶复合物包含至少两个功能上相互作用的RNA分子，它们均作为DNA聚合反应的模板。在此，功能性端粒酶至少包含两个活性位点。
