A novel motif in telomerase reverse transcriptase regulates telomere repeat addition rate and processivity.

ABSTRACT: Telomerase is a specialized reverse transcriptase that adds telomeric DNA repeats onto chromosome termini. Here, we characterize a new telomerase-specific motif, called motif 3, in the catalytic domain of telomerase reverse transcriptase, that is crucial for telomerase function and evolutionally conserved between vertebrates and ciliates. Comprehensive mutagenesis of motif 3 identified mutations that remarkably increase the rate or alter the processivity of telomere repeat addition. Notably, the rate and processivity of repeat addition are affected independently by separate motif 3 mutations. The processive telomerase action relies upon a template translocation mechanism whereby the RNA template and the telomeric DNA strand separate and realign between each repeat synthesis. By analyzing t

SUBMITTER: Xie M 

PROVIDER: S-EPMC2847249 | biostudies-literature | 2010 Apr

REPOSITORIES: biostudies-literature