Telomerase RNA stem terminus element affects template boundary element function, telomere sequence, and shelterin binding. Author Christopher Webb, Virginia Zakian Publication Year 2015 Type Journal Article Abstract The stem terminus element (STE), which was discovered 13 y ago in human telomerase RNA, is required for telomerase activity, yet its mode of action is unknown. We report that the Schizosaccharomyces pombe telomerase RNA, TER1 (telomerase RNA 1), also contains a STE, which is essential for telomere maintenance. Cells expressing a partial loss-of-function TER1 STE allele maintained short stable telomeres by a recombination-independent mechanism. Remarkably, the mutant telomere sequence was different from that of wild-type cells. Generation of the altered sequence is explained by reverse transcription into the template boundary element, demonstrating that the STE helps maintain template boundary element function. The altered telomeres bound less Pot1 (protection of telomeres 1) and Taz1 (telomere-associated in Schizosaccharomyces pombe 1) in vivo. Thus, the S. pombe STE, although distant from the template, ensures proper telomere sequence, which in turn promotes proper assembly of the shelterin complex. Keywords Base Sequence, Sequence Homology, Nucleic Acid, Transcription Factors, Protein Binding, Mutation, Blotting, Western, RNA, Models, Genetic, Telomerase, Chromosomal Proteins, Non-Histone, In Situ Hybridization, Fluorescence, Insulator Elements, Regulatory Sequences, Ribonucleic Acid, Reverse Transcriptase Polymerase Chain Reaction, Reverse Transcription, Schizosaccharomyces, Schizosaccharomyces pombe Proteins, Telomere, Telomere-Binding Proteins, Templates, Genetic, Autophagy-Related Proteins Journal Proc Natl Acad Sci U S A Volume 112 Issue 36 Pages 11312-7 Date Published 2015 Sep 08 ISSN Number 1091-6490 DOI 10.1073/pnas.1503157112 Alternate Journal Proc Natl Acad Sci U S A PMCID PMC4568702 PMID 26305931 PubMedPubMed CentralGoogle ScholarBibTeXEndNote X3 XML