Telomerase: Not Just Black and White,but Shades of Gray

摘要

Telomerase,the telomeric DNA reverse transcriptase,plays a key role in the maintenance of telomeres in mammals and is required for immortalization of primary cells.Inexplicably, telomerase activation is sometimes associated with telomere shortening and inhibition leads not only to apoptosis but also increased tumorigenicity in rapidly renewing tissues of mouse and man.This article reviews the current evidence,both in vitro and in vivo,for telomerase function and the potential mechanisme,downstream of telomerase,in telomere signaling involving both the tumor-suppressor p53-dependent and independent pathways.