Morin G B
Department of Molecular Biophysics and Biochemistry, Howard Hughes Medical Institute, Yale University, New Haven, Connecticut 06510.
Cell. 1989 Nov 3;59(3):521-9. doi: 10.1016/0092-8674(89)90035-4.
I have identified an activity in crude HeLa cell extracts that satisfies the requirements for a human telomere terminal transferase or telomerase. It catalyzes the addition of a 6 nucleotide repeating pattern to oligonucleotide primers containing human or nonhuman telomeric repeat sequences. Direct sequence analyses of reaction products reveal the added sequence to be TTAGGG in all cases. Under optimal conditions 65-70 repeats can be synthesized. The enzyme has the properties of a ribonucleoprotein. Telomerase has previously been observed only in ciliated protozoans, which possess 10(4) - 10(7) macronuclear telomeres. The identification of telomerase in HeLa cells with only approximately 100 telomeres indicates that telomerase-mediated telomere maintenance is conserved throughout eukaryotes.
我在粗制的HeLa细胞提取物中鉴定出一种活性物质,它满足人类端粒末端转移酶或端粒酶的要求。它催化将一个6核苷酸重复序列添加到含有人类或非人类端粒重复序列的寡核苷酸引物上。对反应产物的直接序列分析表明,在所有情况下添加的序列都是TTAGGG。在最佳条件下,可以合成65 - 70个重复序列。该酶具有核糖核蛋白的特性。端粒酶此前仅在纤毛原生动物中观察到,这些原生动物拥有10⁴ - 10⁷个大核端粒。在仅含有约100个端粒的HeLa细胞中鉴定出端粒酶,表明端粒酶介导的端粒维持在整个真核生物中是保守的。