Affordable Access

deepdyve-link
Publisher Website

A conserved motif in Tetrahymena thermophila telomerase reverse transcriptase is proximal to the RNA template and is essential for boundary definition.

Authors
  • Akiyama, Benjamin M1
  • Gomez, Anastassia
  • Stone, Michael D
  • 1 Department of Molecular, Cell, and Developmental Biology, University of California, Santa Cruz, California 95064, USA.
Type
Published Article
Journal
Journal of Biological Chemistry
Publisher
American Society for Biochemistry and Molecular Biology
Publication Date
Jul 26, 2013
Volume
288
Issue
30
Pages
22141–22149
Identifiers
DOI: 10.1074/jbc.M113.452425
PMID: 23760279
Source
Medline
Keywords
Language
English
License
Unknown

Abstract

The ends of linear chromosomes are extended by telomerase, a ribonucleoprotein complex minimally consisting of a protein subunit called telomerase reverse transcriptase (TERT) and the telomerase RNA (TER). TERT functions by reverse transcribing a short template region of TER into telomeric DNA. Proper assembly of TERT and TER is essential for telomerase activity; however, a detailed understanding of how TERT interacts with TER is lacking. Previous studies have identified an RNA binding domain (RBD) within TERT, which includes three evolutionarily conserved sequence motifs: CP2, CP, and T. Here, we used site-directed hydroxyl radical probing to directly identify sites of interaction between the TERT RBD and TER, revealing that the CP2 motif is in close proximity to a conserved region of TER known as the template boundary element (TBE). Gel shift assays on CP2 mutants confirmed that the CP2 motif is an RNA binding determinant. Our results explain previous work that established that mutations to the CP2 motif of TERT and to the TBE of TER both permit misincorporation of nucleotides into the growing DNA strand beyond the canonical template. Taken together, these results suggest a model in which the CP2 motif binds the TBE to strictly define which TER nucleotides can be reverse transcribed.

Report this publication

Statistics

Seen <100 times